How severe is this DTC?

I would say rather severe. In the field, we call a lack of fuel in the burned mixture a “lean” condition. When your engine is idling, you risk causing extreme damage to the engine in the short and long term. With this in mind, always follow your engine maintenance. There must be some diligence here, so let’s keep our engines running smoothly and efficiently. After all, they pull our weight to transport us daily.

What are some of the symptoms of the code?

Symptoms of a P217B fault code may include:

• Irregular engine performance
• Misfire
• Reduced fuel economy
• Rough idle
• Excessive smoke
• Engine noise(s)
• Lack of power
• Unable to climb steep hills
• Reduced throttle response

What are some common causes of the code?

Causes of this P217B fuel injector group supply voltage code may include:

• Faulty or damaged fuel injector(s)
• Damaged wiring harness
• Internal wiring malfunction
• Internal ECM problem
• Connector issue

What are the troubleshooting steps for P217B?

Basic Step #1

The first recommended step is to locate the “group” of sensors that the manufacturer refers to. With this information, you can then find the physical location of the injector(s) and their circuits. This may involve removing many covers and/or engine components to visually access them (if possible). Be sure to inspect the harness for frayed wires. Any worn insulation should be properly repaired with a shrink tube to prevent further and/or future issues.

Basic Step #2

Sometimes water and/or fluids can be “trapped” in the valleys where the injectors are installed. This increases the chances of the sensor connectors, among other electrical connections, corroding at a faster rate than normal. Make sure everything is as expected and that the connector tabs seal the connection properly. Feel free to use an electrical contact cleaner to ensure everything connects and disconnects smoothly, not to mention the increased electrical connectivity in the connections with the use of this product.

Basic Step #3

Check the circuit integrity by following the troubleshooting steps provided by your specific vehicle’s service manual. An example is to disconnect the supply voltage circuit from the ECM and the fuel injector, then using your multimeter, determine whether the wires are in good working order or not.

A test I like to do to quickly determine if there is an open in a particular wire that would help with the P217B code is to perform a “continuity test.” Set your multimeter to RESISTANCE (aka ohm, impedance, etc.), touch one end to one end of the circuit and the other end to the other end. Any value higher than desired may indicate a problem in the circuit. Any issue here will need to be determined by tracing the particular wire you are diagnosing.

How severe is this DTC?

I would say rather severe. In the field, we call a lack of fuel in the burned mixture a “lean” condition. When your engine is idling, you risk causing extreme damage to the engine in the short and long term. With this in mind, always follow your engine maintenance. There must be some diligence here, so let’s keep our engines running smoothly and efficiently. After all, they pull our weight to transport us daily.

What are some of the symptoms of the code?

Symptoms of a P217C fault code may include:

• Irregular engine performance
• Misfire
• Reduced fuel economy
• Irregular idle
• Excessive smoke
• Engine noise(s)
• Lack of power
• Unable to climb steep hills
• Reduced throttle response

What are some common causes of the code?

Causes of this P217C fuel injector group supply voltage code may include:

• Faulty or damaged fuel injector(s)
• Damaged wiring harness
• Internal wiring malfunction
• Internal ECM issue
• Connector problem

What are the troubleshooting steps for P217C?

Basic Step #1

The first recommended step is to locate the “group” of sensors that the manufacturer refers to. With this information, you can then find the physical location of the injector(s) and their circuits. This may involve removing many covers and/or engine components to visually access (if possible). Be sure to inspect the harness for short circuits to other power wires. Any worn insulation should be properly repaired with a shrink tube to avoid further and/or future issues.

Basic Step #2

Sometimes water and/or fluids can be “trapped” in the valleys where the injectors are installed. This increases the chances of the sensor connectors, among other electrical connections, corroding at a faster rate than normal. Ensure everything is as expected and that the connector tabs properly seal the connection. Feel free to use an electrical contact cleaner to make everything connect and disconnect smoothly, not to mention the increased electrical connectivity in the connections with the use of this product.

Basic Step #3

Check the circuit integrity by following the troubleshooting steps provided by your specific vehicle’s service manual. An example is to disconnect the supply voltage circuit from the ECM and the fuel injector, then using your multimeter, determine if the wires are in good working condition or not.

A test I like to do to quickly determine if there is an open in a particular wire that would help with the P217C code is to perform a “continuity test.” Set your multimeter to RESISTANCE (aka ohm, impedance, etc.), touch one end to one end of the circuit and the other end to the other end. Any value higher than desired may indicate a problem in the circuit. Any issue here will need to be determined by tracing the particular wire you are diagnosing.

How severe is this DTC?

I would say rather severe. In the field, we refer to a lack of fuel in the burned mixture as a “lean” condition. When your engine is idling, you risk causing extreme damage to the engine in the short and long term. With this in mind, always follow your engine maintenance. There needs to be some diligence here, so let’s keep our engines running smoothly and efficiently. After all, they carry our weight to transport us daily.

What are some of the symptoms of the code?

Symptoms of a P217D fault code may include:

• Irregular engine performance
• Misfire
• Reduced fuel economy
• Irregular idle
• Excessive smoke
• Engine noise(s)
• Lack of power
• Inability to climb steep hills
• Reduced throttle response

What are some common causes of the code?

Causes of this P217D fuel injector group supply voltage code may include:

• Faulty or damaged fuel injector(s)
• Damaged wiring harness
• Internal wiring malfunction
• Internal ECM issue
• Connector problem

What are the troubleshooting steps for P217D?

Basic Step #1

The first recommended step is to locate the “group” of sensors that the manufacturer refers to. With this information, you can then find the physical location of the injector(s) and their circuits. This may involve removing many covers and/or engine components to visually access them (if possible). Be sure to inspect the wiring harness for broken wires. Any worn insulation should be properly repaired with heat shrink tubing to prevent further and/or future issues.

Basic Step #2

Sometimes water and/or fluids can become “trapped” in the valleys where the injectors are installed. This increases the chances of the sensor connectors, among other electrical connections, corroding at a faster rate than normal. Ensure everything is as expected and that the connector tabs seal the connection properly. Feel free to use an electrical contact cleaner to make everything connect and disconnect smoothly, not to mention the increased electrical connectivity in the connections with the use of this product.

Basic Step #3

Check the circuit integrity by following the troubleshooting steps provided by your specific vehicle’s service manual. One example is to disconnect the supply voltage circuit from the ECM and the fuel injector, then using your multimeter, determine whether the wires are in good working condition or not.

A test I like to perform to quickly determine if there is an open in a particular wire that would help with the P217D code is to do a “continuity test.” Set your multimeter to RESISTANCE (also known as ohm, impedance, etc.), touch one end to one end of the circuit and the other end to the other end. Any value higher than desired may indicate a problem in the circuit. Any issue here will need to be determined by tracing the particular wire you are diagnosing…

How severe is this DTC?

I would say rather severe. In the field, we call a lack of fuel in the burned mixture a “lean” condition. When your engine is idling, you risk causing extreme damage to the engine in the short and long term. With this in mind, always follow your engine maintenance. There must be some diligence here, so let’s keep our engines running smoothly and efficiently. After all, they pull our weight to transport us daily.

What are some of the symptoms of the code?

Symptoms of a P217E fault code may include:

• Irregular engine performance
• Misfire
• Reduced fuel economy
• Irregular idle
• Excessive smoke
• Engine noise(s)
• Lack of power
• Inability to climb steep hills
• Reduced throttle response

What are some common causes of the code?

Causes of this P217E fuel injector group supply voltage code may include:

• Faulty or damaged fuel injector(s)
• Damaged wiring harness
• Internal wiring malfunction
• Internal ECM issue
• Connector problem

What are the troubleshooting steps for P217E?

Basic Step #1

The first recommended step is to locate the “group” of sensors that the manufacturer refers to. With this information, you can then find the physical location of the injector(s) and their circuits. This may involve removing many covers and/or engine components to visually access them (if possible). Be sure to inspect the harness for frayed wires. Any worn insulation should be properly repaired with a shrink tube to avoid further and/or future issues.

Basic Step #2

Sometimes water and/or fluids can be “trapped” in the valleys where the injectors are installed. This increases the chances of the sensor connectors, among other electrical connections, corroding at a faster rate than normal. Ensure everything is as expected and that the connector tabs seal the connection properly. Feel free to use an electrical contact cleaner to make everything connect and disconnect smoothly, not to mention the increased electrical connectivity in the connections with the use of this product.

Basic Step #3

Check the circuit integrity by following the troubleshooting steps provided by your specific vehicle’s maintenance manual. An example is to disconnect the supply voltage circuit from the ECM and the fuel injector, then using your multimeter, determine if the wires are in good working condition or not.

A test I like to do to quickly determine if there is an open in a particular wire that would help with the P217E code is to perform a “continuity test.” Set your multimeter to RESISTANCE (aka ohm, impedance, etc.), touch one end to one end of the circuit and the other end to the other end. Any value higher than desired may indicate a problem in the circuit. Any issue here will need to be determined by tracing the particular wire you are diagnosing.

How severe is this DTC?

I would say rather severe. In the field, we refer to a lack of fuel in the burned mixture as a “lean” condition. When your engine is idling, you risk causing extreme damage to the engine in both the short and long term. With this in mind, always follow your engine maintenance. There needs to be some diligence here, so let’s keep our engines running smoothly and efficiently. After all, they pull our weight to get us around daily.

What are some symptoms of the code?

Symptoms of a P217F fault code may include:

• Irregular engine performance
• Misfire
• Reduced fuel economy
• Rough idle
• Excessive smoke
• Engine noise(s)
• Lack of power
• Inability to climb steep hills
• Reduced throttle response

What are some common causes of the code?

Causes of this P217F fuel injector group supply voltage code may include:

• Faulty or damaged fuel injector(s)
• Damaged wiring harness
• Internal wiring malfunction
• Internal ECM issue
• Connector problem

What are the troubleshooting steps for P217F?

Basic Step #1

The first recommended step is to locate the “group” of sensors that the manufacturer refers to. With this information, you can then find the physical location of the injector(s) and their circuits. This may involve removing many covers and/or engine components to visually access them (if possible). Be sure to inspect the harness for short circuits to other power wires. Any worn insulation should be properly repaired with shrink tubing to prevent further and/or future issues.

Basic Step #2

Sometimes, water and/or fluids can become “trapped” in the valleys where the injectors are installed. This increases the chances of the sensor connectors, among other electrical connections, corroding at a faster rate than normal. Ensure everything is as expected and that the connector tabs seal the connection properly. Feel free to use an electrical contact cleaner to allow everything to connect and disconnect smoothly, not to mention the increased electrical connectivity in the connections with the use of this product.

Basic Step #3

Check the circuit integrity by following the troubleshooting steps provided by your specific vehicle’s service manual. An example is to disconnect the supply voltage circuit from the ECM and the fuel injector, then using your multimeter, determine whether the wires are in good working condition or not.

A test I like to perform to quickly determine if there is an open in a particular wire that would help with the P217F code is to do a “continuity test.” Set your multimeter to RESISTANCE (aka ohm, impedance, etc.), touch one end to one end of the circuit and the other end to the other end. Any value higher than desired may indicate a problem in the circuit. Any issue here will need to be determined by tracing the particular wire you are diagnosing.

Understanding the Toyota P1443 Diagnostic Trouble Code

The P1443 diagnostic trouble code is a manufacturer-specific code primarily associated with Toyota and Lexus vehicles. This code indicates a malfunction within the Evaporative Emission Control (EVAP) system, specifically related to the Vent Control Valve or its associated circuit. The EVAP system is a critical component designed to prevent fuel vapors from the gas tank from escaping into the atmosphere. When the Powertrain Control Module (PCM) or Engine Control Module (ECM) detects an irregularity in the electrical current, voltage, or operational signal of the vent control valve circuit, it will store the P1443 code and illuminate the Check Engine Light.

What is the EVAP System and Its Role?

The Evaporative Emission Control (EVAP) system is a sealed network that captures fuel vapors from the fuel tank. Instead of being released into the environment, these vapors are stored in a charcoal canister and later purged into the engine’s intake manifold to be burned during normal combustion. This process is essential for reducing hydrocarbon emissions and meeting environmental regulations. The system consists of several key components, including the fuel tank, gas cap, charcoal canister, purge valve, and the vent control valve, which is the central figure in a P1443 code scenario.

The Specific Function of the Vent Control Valve (VSV)

The Vent Control Valve, also known as the Vacuum Switching Valve (VSV) for ventilation, is an electrically operated solenoid valve. Its primary function is to control the flow of air and fuel vapor into and out of the charcoal canister. It opens to allow fresh air to enter the system during the purging process and closes to seal the system during leak tests and when the engine is off. A malfunction of this valve or its control circuit, as indicated by P1443, prevents the vehicle’s computer from properly managing this process, leading to potential emissions test failures and drivability issues.

Common Symptoms and Causes of a P1443 Code

When a Toyota vehicle sets a P1443 code, the symptoms can range from unnoticeable to quite pronounced. It is crucial to address this code promptly, as a faulty EVAP system can affect engine performance and will cause a vehicle to fail an emissions inspection.

Recognizing the Symptoms of P1443

• Illuminated Check Engine Light: The most common and often the only initial symptom.
• Failed Emissions Test: The vehicle will not pass a state or local emissions inspection due to the detected EVAP system fault.
• Fuel Odor: In some cases, a faint smell of gasoline may be noticeable near the vehicle if vapors are not being properly contained.
• Decreased Fuel Efficiency: A poorly functioning EVAP system can, in rare instances, lead to a slight reduction in gas mileage.
• Rough Idle or Hard Starting: This is less common but can occur if the EVAP system’s purge function is also compromised.

Root Causes of the P1443 Code

• Faulty Vent Control Valve (VSV): The solenoid inside the valve can fail electrically (open or short circuit) or mechanically (stuck open or closed).
• Damaged Wiring or Connectors: Corroded, broken, or shorted wires in the valve’s control circuit are a frequent cause.
• Poor Electrical Connections: A loose or corroded connector at the vent valve or the ECM can disrupt the signal.
• Blocked or Pinched Vent Hose: A physical obstruction in the hose leading to or from the vent valve can prevent it from operating correctly.
• Defective Charcoal Canister: While less common, a saturated or damaged canister can cause backpressure and trigger this code.
• Faulty Engine Control Module (ECM): This is a rare cause, but a malfunctioning PCM/ECM cannot be ruled out entirely.

Step-by-Step Diagnostic and Repair Procedure for P1443

Diagnosing a P1443 code requires a systematic approach, starting with the simplest and most common causes before moving to more complex components. You will need a basic set of hand tools and a digital multimeter (DMM).

Step 1: Preliminary Visual Inspection

Begin with a thorough visual inspection of the EVAP system. The vent valve is typically located near the charcoal canister, which is often found underneath the vehicle, behind a rear wheel well or in the spare tire wheel area. Look for any obvious signs of damage.

• Inspect all EVAP hoses for cracks, brittleness, disconnections, or being pinched.
• Check the electrical connector on the vent control valve for corrosion, bent pins, or a loose fit.
• Examine the wiring harness leading to the valve for any chafing, burns, or damage.

Step 2: Testing the Vent Control Valve (VSV)

If the visual inspection reveals no issues, the next step is to test the vent valve itself. You will need to locate it, which can vary by Toyota model (e.g., Camry, Corolla, RAV4, Highlander). Consult a vehicle-specific repair manual for its exact location.

• Resistance Test: Disconnect the electrical connector from the valve. Using a multimeter set to Ohms (Ω), measure the resistance across the two terminals of the valve solenoid. Compare your reading to the manufacturer’s specifications (typically between 20-40 Ω at room temperature). A reading of infinite resistance (open circuit) or zero resistance (short circuit) indicates a faulty valve.
• Mechanical Function Test: You can apply battery voltage (12V) directly to the valve terminals (using fused jumper wires) to hear an audible “click.” If it doesn’t click, the solenoid is mechanically seized. Also, use a hand-held vacuum pump to check if the valve holds vacuum when energized and releases it when de-energized.

Step 3: Checking the Electrical Circuit

If the valve tests good, the problem lies in the wiring or the ECM. With the valve connector still disconnected, turn the ignition to the “ON” position (engine off).

• Power Supply Test: Back-probe the connector’s power wire (refer to a wiring diagram) with the multimeter set to Volts DC. You should read battery voltage (approx. 12V). If not, there is an open or short in the power supply circuit from the fuse/ECM.
• Ground Circuit Test: Check the ground circuit for continuity. A wiring diagram is essential to identify the correct pins for testing.

Step 4: Clearing the Code and Verifying the Repair

Once the faulty component (valve, wiring, connector) has been repaired or replaced, the final step is to clear the code and confirm the fix.

• Use your OBD2 scanner to clear the P1443 code from the ECM’s memory.
• Take the vehicle for a test drive, ensuring you complete a full drive cycle. This allows the ECM to run its self-tests on the EVAP system.
• Rescan the system to ensure the code does not return. If it does, you may have an intermittent fault or an additional underlying issue.

Conclusion and Professional Considerations

Diagnosing and repairing a P1443 code on a Toyota vehicle is a manageable task for a knowledgeable DIYer with the right tools. The process hinges on a logical sequence of inspecting, testing, and verifying. The vent control valve (VSV) is the most common culprit and is generally a straightforward component to replace. However, if the diagnosis points towards a wiring fault deep in the harness or a potential ECM issue, it may be prudent to seek the assistance of a professional automotive technician. They possess advanced diagnostic tools, such as a scan tool that can actively command the vent valve on and off, which can significantly streamline the troubleshooting process. Addressing a P1443 code promptly will restore your vehicle’s emissions system to proper function, ensure it passes smog tests, and maintain its environmental efficiency.

Symptoms

Symptoms of a P2180 engine code may include:

• Malfunction Indicator Lamp (MIL) illuminated
• Lack of power
• Occasional misfires
• Poor fuel economy

Causes

Possible causes for this code definition include:

• Faulty Air/Fuel Ratio sensor or Bank 2 Oxygen sensor (AFR/O2)
• Faulty Mass Air Flow sensor (MAF)
• Rarely – Faulty Powertrain Control Module (PCM)

Diagnostic and Repair Procedures

A good starting point is always to check the Technical Service Bulletins (TSBs) for your specific vehicle. Your issue might be a known problem with a published fix from the manufacturer, which can save you time and money during diagnosis.

First, note if there are any other diagnostic trouble codes. If any are related to the fuel system, diagnose those first. Misdiagnosis is known to occur if this code is diagnosed before related fuel system codes have been thoroughly diagnosed and dismissed.

Once located, visually inspect the connectors and wiring. Look for chafing, rubbing, bare wires, burns, or melted plastic. Disconnect the connectors and carefully inspect the terminals (the metal parts) inside. Check if they appear corroded, burnt, or possibly greenish compared to the normal metallic color you’re used to seeing. You can get electrical contact cleaner at any auto parts store if terminal cleaning is needed. If that’s not possible, find 91% rubbing alcohol and a soft plastic-bristled brush to use. Then, let them air dry, get some dielectric silicone compound (the same type used for bulb sockets and spark plug wires), and apply it where the terminals make contact.

If you have a scan tool, clear the diagnostic codes from memory and see if this code returns. If it doesn’t, the connections were likely your issue.

If the code returns, we’ll need to test the voltage signal from the MAF sensor to the PCM. Monitor the MAF sensor voltage on your scan tool. If a scan tool isn’t available, test the signal from the MAF sensor with a Digital Volt-Ohm Meter (DVOM). With the sensor connected, attach the red voltmeter lead to the MAF sensor signal wire and the black voltmeter lead to ground. Start the engine and monitor the MAF sensor input. As engine RPM increases, the MAF sensor signal should increase. Check the manufacturer’s specifications, as there may be a chart indicating the voltage at a given RPM. If it fails this test, replace the MAF sensor and retest.

If the previous tests passed and the code is still present, monitor the Air/Fuel Ratio sensor or Oxygen sensor (AFR/O2). If it continuously indicates the engine is running rich, locate all possibilities that could cause a rich-running engine. These include:

• Fuel system, including fuel pressure regulator/fuel pressure
• Fuel pressure sensor
• Fuel injectors
• Post-catalytic converter Oxygen sensor
• EVAP system, including the tank purge control valve
• If the Bank 2 AFR/O2 sensor indicates the engine is running normally or even lean, a PCM may be suspected once all other issues have been ruled out.

Again, it cannot be overemphasized that all other codes must be diagnosed before this one, as issues causing other codes to set can also trigger this one.

Symptoms

• The engine temperature gauge indicates a temperature higher or lower than normal. If the vehicle does not have a temperature gauge, it will have a “red” temperature warning light, meaning the engine is already overheating and must be stopped immediately.
• If the gauge is faulty or goes unnoticed, an overheating engine will cause the coolant to boil, producing steam, the radiator/reservoir will overflow, and in critical stages, the engine will start knocking, lose power, and finally seize.
• If the engine runs cold, the fuel mixture will be rich, leading to poor fuel economy, the heater will not work well, and the temperature gauge will indicate colder than normal. All engines are designed to expand to a predetermined point as they heat up. Maintaining the correct operating temperature is essential for proper piston ring sealing.

Effects on the Engine

Running too cold leads to overheating. The effects of running too cold occur over time and are correctable, while overheating is always catastrophic if not addressed quickly. A few minutes of severe overheating and the engine will be destroyed.

Mild overheating typically results in a blown head gasket, which is an expensive repair. Severe overheating will cause the pistons to expand faster than the cylinder block, leading to seizure in the cylinder bores for which there is no repair.

Procedures and Protocol

Due to the wide range of possibilities for overheating as the cause of code P2181, the following strategy will be used. The diagnostic flow will be used from the perspective of an automotive technician. It will start from the most commonly encountered to the least.

Warning: Never open a radiator cap unless the engine is barely warm or cold. The cooling system is under pressure, and the common temperature is 195 degrees, while an overheating engine can exceed 280 degrees. Third-degree burns will certainly occur.

Diagnostic Steps

and Possible Solutions

Tools Used to Diagnose Overheating Issues:

• Temperature scan tool
• Voltmeter
• Set of alligator clip jumper wires
• Scan tool to clear codes
• Cooling system pressure tester
• Service manual

Engine Too Cold:

• Replace the thermostat.

Engine Overheating:

• Plug the code scanner into the OBD port and turn on the key. Check for any other codes. A coolant temperature sensor code will cause the radiator fans to malfunction.
  With the engine cold, remove the radiator cap and check the coolant level. Use the pressure tester to check for leaks in the system. This includes the radiator, hoses, block, intake, and heater core.
• If the engine temperature is normal while driving but overheats when idling, the radiator fan is malfunctioning.
• Check the serpentine belt tension for proper tightness. Faulty belt tensioners are common and allow belt slippage. Check for leaks around the water pump. For those driven by the timing belt, coolant leaks from the bottom of the belt cover. If the water pump is exposed, check if the pulley wobbles, indicating a worn water pump bearing.
  Check that an engine-driven fan does not wobble and does not leak around the fan clutch. Spin the fan by hand. A good fan clutch offers some resistance. An unusually slow fan with the engine running indicates a faulty fan clutch.
• Check the coolant level sensor on the side of the radiator by referring to the service manual.
• If the vehicle has a radiator cap, leave it off, start the engine, and let it warm up. Monitor the engine temperature with the scan tool, and when the temperature approaches 190 degrees, watch for coolant flow from the inner cores of the radiator. If no flow is detected above 195 degrees, replace the cap and stop the engine. The thermostat is faulty.
• If the radiator starts to flow, replace the cap and let the engine reach 205 degrees before shutting it off. If the electric fans do not turn on, shut off the engine.
• Check the engine fan fuse and relays in the driver’s side fender relay and fuse box. Their location is indicated on the underside of the cover.
• Check the fan operation by disconnecting the wiring pigtail. Use a jumper wire from the ground terminal to a good ground and from the power terminal to the battery. If the fan does not run, replace it. If it runs, check the wiring at the fuse and coolant temperature sensor for loose connections, pushed-out connector pins, or burnt wiring.
• Check for a blown head gasket.

Symptoms

Symptoms of a DTC P2182 code can range from nothing more than the illumination of the “check engine” light to one or more of the following:

• The MIL (Malfunction Indicator Lamp) will always illuminate
• The vehicle may be hard to start
• May blow a lot of black smoke and run extremely rich
• The engine may want to die or backfire through the exhaust pipe
• The engine may idle roughly and increased NOx emissions may be apparent (requires a gas analyzer)
• Cooling fans may run all the time when they shouldn’t, or not at all when they should

Causes

Usually, the cause can be attributed to a faulty ECT sensor, but this doesn’t rule out the following:

• Damaged wiring or connector to ECT sensor #2
• Open or short circuit in the reference or signal circuit
• Open or short circuit in the ECT #2 signal circuit
• Faulty PCM

Possible Solutions

1. Visually inspect ECT sensor #2 for any damage to the wiring or connector and repair if necessary. Then, if you have access to a scanner, determine what the engine temperature is. (If you don’t have access to a scan tool, using the dashboard temperature gauge may not be an effective way to determine coolant temperature. This is because code P2182 refers to ECT SENSOR #2, and the dashboard gauge is typically operated by a single-wire SENDER. Basically, a different sensor that the code does not refer to.)

2. If the engine temperature is abnormally high, around 280 degrees F, that’s abnormal. Disconnect the sensor from the engine and see if the signal drops to, say, negative 50 degrees. If it does, then it’s highly likely that the sensor is faulty, internally shorted, causing it to send a low-resistance signal to the PCM. However, if you want to be sure it’s the sensor and not the wiring, you can perform a few tests. With the ECT sensor disconnected, check that you have 5 volts on the reference circuit with KOEO (Key On Engine Off). You can also check the sensor’s resistance to ground using an ohmmeter. The resistance of a normal sensor to ground will vary somewhat by vehicle, but basically, if the engine temperature is around 200 degrees F, the resistance will be around 200 Ohms. If the temperature is around 0 degrees F, the resistance will be over 10,000 Ohms. With this test, you should be able to determine if the sensor’s resistance matches the engine temperature. If it’s not accurate based on your engine’s temperature, you likely have a faulty sensor.

3. Now, if the engine temperature according to the scanner is around 280 degrees F and disconnecting the sensor doesn’t cause the reading to drop to negative 50 degrees F, but it stays at the same high-temperature reading, then you’ll need to repair the short circuit on the signal circuit (ground) to the PCM. It’s shorted directly to ground somewhere.

4. If your engine temperature reading according to the scanner shows negative 50 degrees F or so, (and you don’t live in the Arctic!) disconnect the sensor and check for a 5V reference present at the sensor.

5. If there isn’t one, check at the PCM connector for the proper 5V reference. If it’s present at the PCM connector, repair the open or short in the 5V reference from the PCM. If there is no 5V reference present at the PCM connector, then you’ve completed your diagnosis and you may have a faulty PCM. 6. If the 5V reference circuit is intact, check the ground signal to the PCM using the previous ground resistance test. If the resistance isn’t normal for the engine temperature, measure the resistance of the ground signal wire to the PCM by removing the ground signal wire from the PCM connector. The wire should have no resistance when disconnected from the PCM to the sensor. If it does, repair the open signal to the PCM. If there’s no resistance on the ground signal wire and the sensor resistance test is normal, then suspect a faulty PCM.

Symptoms

There may be no noticeable symptoms if the problem is very intermittent, but the following events may occur:

• MIL (Malfunction Indicator Lamp) illumination
• Poor driving
• Black smoke at the exhaust pipe
• Poor fuel economy
• May not idle
• May experience stalling or misfires

Causes

Potential causes of code P2183 include:

• Missing or stuck-open thermostat
• Faulty ECT sensor No. 2
• Short or open in the signal wire
• Short or open in the ground wire
• Poor connections in the wiring
• ECT sensor

Possible Solutions

If there are other ECT sensor codes, diagnose them first.

Using a scan tool, check ECT readings #1 & #2. On a cold engine, it should match the IAT reading or be equal to the ambient (outside) temperature reading. If it matches the IAT or ambient temperature, check the freeze frame data on your scan tool (if available). The recorded data should tell you what the ECT reading was when the fault occurred.

a) If the recorded information indicates that the engine coolant reading was at the coldest extreme (approximately -30°F), this is a good indication that the ECT resistance was intermittently high (unless you live in Anchorage!) Check for an open in the ground and signal circuits of the ECT sensor and repair if necessary. If they appear correct, warm up the engine while monitoring the ECT for any intermittent high or low jumps. If there is, replace the ECT.

b) If the recorded information indicates that the engine coolant reading was at the hottest extreme (approximately 250+°F), this is a good indication that the ECT resistance was intermittently low. Check for a short to ground in the signal circuit and repair if necessary. If it appears correct, warm up the engine while monitoring the ECT for any intermittent high or low jumps. If there is, replace the ECT.