What is the P0068 Code?

The P0068 fault code is a generic powertrain code that indicates an abnormal correlation between the Throttle Position Sensor (TPS) and the Mass Air Flow (MAP/MAF) sensor. This issue, present in most vehicles (1996 and newer), indicates a disparity in the air intake data received by the Powertrain Control Module (PCM), preventing it from properly regulating the air-fuel mixture and ignition timing.

Symptoms of the P0068 Code

• ⚠️ Check Engine Light illuminated
• 🔁 Rough idling or engine misfires
• 📉 Loss of power and difficulty accelerating
• ⛽ Increased fuel consumption
• 🚗 Possible stalling or very rough idle

Possible Causes of the P0068 Fault

• 🔧 Air leak or vacuum leak between the MAF sensor and the intake manifold
• 🧽 Dirty or clogged air filter
• 🔌 Corroded, loose, or damaged electrical connectors
• 📏 Faulty MAF or MAP sensor
• 🚗 Malfunctioning Throttle Position Sensor (TPS)
• 🛢️ Throttle body carbon buildup (carbon deposits)
• 🧩 Intake manifold leak
• 🧹 Obstruction in the air intake duct or MAP sensor hose

Diagnosis and Solutions for the P0068 Code

To diagnose and resolve a P0068 code, follow these methodical steps. Equip yourself with a multimeter, test probe, carburetor cleaner, and intake cleaner.

1. Visual Inspection and Cleaning

• Check and replace the air filter if necessary.
• Inspect the hoses and clamps between the MAF sensor and the throttle body (tightness, cracks).
• Check the condition of the vacuum lines on the manifold.
• Clean the throttle body and carbon deposits using an appropriate product.

2. Checking Connectors and Sensors

• Disconnect and inspect the sensor connectors (MAF, MAP, TPS) for corrosion or damaged pins.
• Use contact cleaner to improve the connection if necessary.

3. Testing the MAF Sensor (Mass Air Flow Sensor)

• Engine off, ignition on. Connect the multimeter to the MAF connector (3 wires: +12V, ground, signal).
• Check for 12V at the power terminal. Absence = fuse or wiring problem.
• Check the ground (should be < 100 mV).
• If power and ground are correct but the problem persists, the MAF sensor is likely faulty.

4. Testing the TPS Sensor (Throttle Position Sensor)

• Ignition on, engine off. Connect the multimeter to the signal wire (often blue) and ground.
• The voltage should be approximately 0.5V at closed throttle and gradually increase to ~5V at wide open throttle. An irregular variation indicates a faulty TPS.

5. Testing the MAP Sensor (Manifold Absolute Pressure Sensor)

• Ignition on, engine off: voltage approximately 5V.
• Engine at idle: voltage between 0.5V and 1.5V (depending on altitude).
• The voltage should react instantly to throttle opening (drop then rise). No reaction = faulty sensor.

6. Searching for Air Leaks

• Start the engine and spray carburetor cleaner around the manifold and gaskets.
• A change in engine RPM indicates a leak. Caution: Handle with care to avoid contact with eyes.

Conclusion

The P0068 code is often related to an air intake or sensor problem. Always start with the simplest checks (leaks, filters, connectors) before replacing expensive sensors. If the problem persists after these checks, consultation with an advanced diagnostic tool (such as Tech II) or a professional is recommended.

💡 Tip: Not sure you can perform these checks yourself? Entrust the diagnosis to a qualified mechanic for an accurate diagnosis and reliable repair.

What is the P0069 code?

The error code P0069 indicates an inconsistency between the readings from the Manifold Absolute Pressure (MAP) sensor and the Barometric Pressure (BARO) sensor. This generic powertrain diagnostic code applies to most OBD2-equipped vehicles but is more common in certain Audi, Ford, Mazda, Mitsubishi, Saturn, and VW models.

The MAP sensor converts engine vacuum into an electrical signal for the Powertrain Control Module (PCM). The PCM also uses data from other sensors, such as the Mass Air Flow (MAF) sensor and the Throttle Position Sensor (TPS), to calculate engine load and altitude. The P0069 code triggers when the signals from the MAP and BARO sensors show an abnormal correlation, either at startup or at full throttle.

Symptoms of the P0069 code

• Malfunction Indicator Lamp (MIL) illuminated
• Hesitation or jerking during acceleration
• Reduced engine performance
• Decreased fuel economy

Possible causes

• Common cause: Clogged or cracked vacuum line between the intake manifold and the MAP sensor
• Common cause: Poor engine condition (spark plugs, clogged air filters, etc.)
• Possible cause: Faulty MAP or BARO sensor
• Rare cause: PCM (Powertrain Control Module) failure

Solutions and diagnostic procedures

Preliminary advice: Check your manufacturer’s Technical Service Bulletins (TSBs). A known fix may exist for your model.

1. Visual inspection: Locate the MAP sensor near the intake manifold. Inspect electrical connectors and wiring for any signs of wear, corrosion, or damage. Clean the terminals with an appropriate product if necessary.
2. Vacuum circuit check: Verify the seal and absence of obstruction in the vacuum line connecting the manifold to the sensor. Engine vacuum must be properly transmitted.
3. Using a diagnostic tool: Clear the codes and perform a drive test. If the P0069 code returns, measure the MAP sensor values (PID) with the scan tool. At sea level, the KOEO (Key On Engine Off) reading should be approximately 100 kPa. It should vary significantly at idle and during acceleration.
4. Replacement: If all other causes are ruled out, replacing the MAP sensor is the most likely solution. A faulty PCM is rare but cannot be ruled out until after sensor replacement.

Important note: Replacing a PCM requires vehicle-specific programming. It is recommended to consult an automotive diagnostic professional for complex steps.

Code P006C: Definition and Explanation

The diagnostic trouble code P006C is a generic powertrain code (DTC) indicating that the Powertrain Control Module (PCM) has detected an inconsistency between the signals from the Manifold Absolute Pressure (MAP) sensor and the turbocharger inlet pressure sensor. This code primarily affects vehicles equipped with forced induction (turbocharger or supercharger).

Symptoms of Code P006C

When this trouble code is stored, you may observe one or more of the following symptoms:

• ➤ Reduced engine performance
• ➤ Noticeable decrease in boost efficiency
• ➤ Hesitation during acceleration
• ➤ Air-fuel mixture too rich or too lean
• ➤ Abnormal whistling sounds from the intake system

Possible Causes of P006C Fault

Several factors can cause this code:

• ➤ Faulty MAP sensor
• ➤ Malfunctioning turbo pressure sensor
• ➤ Damaged wiring or connector (short circuit or open circuit)
• ➤ Vacuum leak or restriction in the air intake
• ➤ Clogged air filter
• ➤ PCM failure or need for update

Diagnosis and Troubleshooting of Code P006C

1. Preliminary Visual Inspection:

• Check the condition and connection of the MAP and turbo pressure sensors.
• Inspect intake hoses and ducts for possible disconnections or leaks.
• Check the air filter and replace if necessary.

2. Required Tools:

• OBD2 scanner, digital multimeter (DVOM), vacuum gauge, technical information source (e.g., AllData, Mitchell1).

3. Diagnostic Steps:

• Start by measuring engine vacuum using a vacuum gauge.
• Use a scanner to read trouble codes and freeze frame data.
• Test the power supply (5V) and ground of the sensor connectors with a multimeter.
• Measure sensor resistance (with power off) and compare to manufacturer specifications.
• Check each sensor’s signal (with power on) by referring to pressure/voltage curves.
• Verify continuity and absence of short circuits in the wiring up to the PCM.

4. Special Cases:

• If all tests are conclusive, PCM reprogramming or replacement may be necessary.
• Check Technical Service Bulletins (TSB) for recurring issues with your vehicle model.

Conclusion and Call to Action

Code P006C directly affects your engine’s performance and efficiency. Prompt intervention is recommended.

💡 Tip: If you’re not comfortable with these procedures, consult a professional mechanic equipped with advanced diagnostic tools.

Need help interpreting your sensor values? Use our interactive guide or contact an online expert for a personalized diagnosis.

Code P006D: Definition and Explanation

The error code P006D is a generic powertrain diagnostic trouble code (DTC) indicating that the Powertrain Control Module (PCM) has detected an inconsistency between the signals from the Barometric Pressure Sensor (BARO) and the Turbocharger/Compressor Inlet Pressure Sensor. This code specifically applies to vehicles equipped with a forced induction system (turbo or supercharger).

Symptoms of Code P006D

When this code is stored, the following symptoms may appear:

• ➤ Reduced engine performance
• ➤ Decreased fuel efficiency (increased consumption)
• ➤ Delayed or hesitant acceleration
• ➤ Rich or lean air-fuel mixture
• ➤ Whistling or abnormal intake noises during acceleration
• ➤ Malfunction Indicator Lamp (MIL) illuminated on the dashboard

Possible Causes of the Fault

Several factors can cause the P006D code:

• ➤ Faulty Sensor: Defective BARO sensor or turbo/compressor inlet pressure sensor.
• ➤ Electrical Issues: Damaged wiring, corroded, loose, or short-circuited connectors.
• ➤ Air Induction Problems: Obstructed air intake, dirty air filter, leaks in the intake ducts.
• ➤ Mechanical Fault: Insufficient engine vacuum due to an internal issue.
• ➤ PCM Failure: Programming error or failure of the control module.

How to Diagnose Code P006D?

Diagnosis requires an OBD2 scanner, a digital multimeter (DVOM), a vacuum gauge, and access to vehicle technical data (wiring diagrams, reference values).

Diagnostic Steps:

1. Visual Inspection: Check the condition of cables, connectors, and intake ducts. Ensure the air filter is clean and the turbo pressure sensor connector was not forgotten after maintenance.
2. Engine Vacuum Test: Using the vacuum gauge, measure engine vacuum and compare it to manufacturer specifications. Insufficient vacuum indicates a mechanical issue that should be addressed first.
3. Reading Codes and Freeze Frame Data: Use the scanner to read all fault codes and freeze frame data recorded at the time of the malfunction. Note this information and clear the codes to see if P006D returns.
4. Sensor Electrical Testing:
   • Check for reference voltage (5V) and ground at the connectors of both sensors with the multimeter.
   • Test the resistance of the sensors (disconnected) and compare to manufacturer-specific values.
   • With the engine running (KOER), measure the voltage signal of each sensor and verify it changes correctly with pressure (refer to voltage/pressure curves in technical data).
5. Wiring Test: If the sensors are functional, check continuity and absence of short circuits in the wires between the sensors and the PCM using wiring diagrams.
6. PCM: If everything else is correct, reprogramming or replacing the PCM may be necessary.

Conclusion and Call to Action

Code P006D directly affects performance and fuel economy. Its diagnosis can be complex and often requires specialized tools and precise technical documentation.

💡 Tip: Always consult your vehicle’s Technical Service Bulletins (TSBs) to check for known issues and manufacturer-recommended solutions.

If you are not comfortable with these procedures, consult a professional mechanic for an accurate diagnosis and reliable repair.

What is the P0070 code?

The P0070 error code is a generic powertrain code indicating a malfunction in the Ambient Air Temperature (AAT) sensor circuit. This sensor, found in most OBDII-equipped vehicles (including Audi, BMW, Chrysler, Dodge, Ford, Jeep, Mazda, Mitsubishi, and VW), converts outside air temperature into an electrical signal sent to the Powertrain Control Module (PCM).

This data is crucial for the proper operation of the air conditioning system and displaying the outside temperature on the dashboard. The PCM compares the AAT sensor signal with those from the Intake Air Temperature (IAT) and Engine Coolant Temperature (ECT) sensors at startup. The P0070 code triggers when these values show an abnormal discrepancy.

Symptoms of the P0070 code

Several signs can alert you to a problem with the AAT sensor:

• The Malfunction Indicator Lamp (MIL) is illuminated on your dashboard.
• Issues with air conditioning operation (irregular or ineffective cooling).
• An incorrect reading of the outside temperature on the dashboard or center console display.

Possible causes of the P0070 error

The main causes of this fault code are typically electrical:

• An open or short circuit (to ground or voltage) in the wiring to the sensor.
• A faulty AAT sensor (the most common cause after connection issues).
• A PCM failure (rare, but possible).

How to diagnose and fix the P0070 code?

1. Check Technical Service Bulletins (TSBs)
First, consult your manufacturer’s TSBs. A known fix may exist for your model, saving you from a lengthy and costly diagnosis.

2. Visual inspection
Locate the AAT sensor, usually positioned behind the grille or front bumper. Inspect the connector and wiring for any signs of wear, corrosion (greenish tint), burning, or exposed wires. Clean the terminals with contact cleaner and apply dielectric grease.

3. Testing the AAT sensor
Using a multimeter (DVOM), measure the sensor’s resistance (disconnected) and compare it to reference values based on ambient temperature. A resistance of 0 Ω or infinite (OL) indicates a faulty sensor.

4. Testing the electrical circuit
With a scan tool, read the AAT sensor signal voltage (ignition on). It should be around 5V. By shorting the two terminals of the harness connector (ignition off then on), the reading should drop to near 0V. If these values are not met, the circuit to the PCM is faulty.

5. Replacement and reset
If all wiring is correct, replace the AAT sensor. Then clear the fault codes with your diagnostic tool. If the code does not return, the problem is solved. If the code persists, a PCM failure, although rare, is possible.

🔧 Need help?

Electrical diagnosis can be complex. If you’re not comfortable with these steps, consult a professional mechanic for an accurate diagnosis. Replacing a PCM requires specific vehicle programming.

What is the P0071 code?

The P0071 error code is a generic powertrain-related code that indicates a performance issue with the Ambient Air Temperature (AAT) sensor. This sensor, found on most OBDII-equipped vehicles (including Audi, BMW, Chrysler, Dodge, Ford, Jeep, Mazda, Mitsubishi, and VW), is responsible for converting the outside air temperature into an electrical signal sent to the Powertrain Control Module (PCM).

This data is crucial for regulating the air conditioning system and displaying the outside temperature on the dashboard. The PCM compares the AAT sensor signal with those from the Intake Air Temperature (IAT) sensor and the Engine Coolant Temperature (ECT) sensor upon startup, after a cooldown period. An abnormal discrepancy between these values triggers the P0071 code.

Symptoms of the P0071 code

Several signs can alert you to a malfunction of the AAT sensor:

• The malfunction indicator lamp (check engine) is illuminated.
• Poor operation or inefficiency of the air conditioning system.
• Incorrect or missing display of the outside temperature on the dashboard or console.

Possible causes of the P0071 error

The origins of this code are primarily electrical, but mechanical faults are also possible:

• Open or shorted signal circuit (to ground or to voltage).
• Faulty AAT sensor (the most common cause after connection issues).
• Incorrect mounting location or sensor left hanging (mechanical defect).
• PCM failure (rare).

How to diagnose and fix a P0071 code?

Always start by consulting your manufacturer’s Technical Service Bulletins (TSBs) to check for any known issues.

1. Visual Inspection

Locate the AAT sensor, usually positioned in front of the radiator. Inspect the connector and wiring for any signs of wear, corrosion (greenish tint), or burning. Clean the terminals with contact cleaner and a non-abrasive brush if necessary, then apply dielectric grease.

2. Sensor Testing

Using a multimeter (DVOM) in ohmmeter mode, measure the resistance of the (disconnected) sensor and compare it to the reference values for the ambient temperature. A reading of 0 Ω or infinite resistance (OL) indicates a faulty sensor.

3. Circuit Testing

Reconnect the sensor and use a diagnostic tool to read the voltage or temperature reported by the sensor to the PCM. With the ignition on, the voltage should be around 5V. By shorting the two terminals of the harness connector (ignition off), the reading should drop close to 0V. If these values are not observed, the electrical circuit or the PCM is at fault.

4. Replacement and Conclusion

If the previous tests point to the sensor, replace it. Then, clear the codes with your diagnostic tool and perform a road test to verify that the code does not return. If the problem persists, the PCM might be faulty, but this is rare. If in doubt, consult an automotive professional.

Need help diagnosing your vehicle? Consult a partner garage or invest in a reliable OBD2 diagnostic tool to perform these checks yourself.