P2488 Possible Causes

• Faulty Exhaust Gas Temperature Sensor (EGTS), Bank 2 Sensor 5
• Exhaust Gas Temperature Sensor, Bank 2 Sensor 5 wiring harness is open or short-circuited
• Poor electrical connection in Bank 2 Sensor 5 circuit of the Exhaust Gas Temperature Sensor
• Exhaust leaks
• Excessive particulate buildup on the sensor

How to Fix Code P2488

Check the “Possible Causes” listed above. Visually inspect the wiring harness and related connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

P2488

Symptoms

Possible

Check Engine Light illuminated (or Service Engine Soon warning light)

P2488 Meaning

The Powertrain Control Module (PCM) continuously monitors the Exhaust Gas Temperature Sensor (EGTS) for proper circuit continuity and out-of-range high values. The EGTS is located upstream of the Diesel Oxidation Catalyst (DOC) and/or upstream of the Diesel Particulate Filter (DPF). The EGTS detects exhaust gas temperature and converts it to voltage, sending it back to the PCM with the voltage signal to control engine conditions for effective emission reduction. The PCM sets OBDII code P2488 when the exhaust gas temperature sensor is outside factory specifications.

P2489 Possible Causes

• Faulty Exhaust Gas Temperature Sensor (EGTS), Bank 2 Sensor 5
• Exhaust Gas Temperature Sensor, Bank 2 Sensor 5 wiring harness is open or short-circuited
• Poor electrical connection in Bank 2 Sensor 5 circuit of the Exhaust Gas Temperature Sensor
• Exhaust leaks
• Excessive particulate buildup on the sensor

How to Fix Code P2489

Check the “Possible Causes” listed above. Visually inspect the wiring harness and related connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

P2489

Symptoms

Possible

Check Engine Light illuminated (or Service Engine Soon warning light)

P2489 Meaning

The Powertrain Control Module (PCM) continuously monitors the Exhaust Gas Temperature Sensor (EGTS) for proper circuit continuity and out-of-range high values. The EGTS is located upstream of the Diesel Oxidation Catalyst (DOC) and/or upstream of the Diesel Particulate Filter (DPF). The EGTS detects exhaust gas temperature and converts it to voltage, sending it back to the PCM with the voltage signal to control engine conditions for effective emission reduction. The PCM sets OBDII code P2489 when the Exhaust Gas Temperature Sensor is outside factory specifications.

How severe is this DTC?

When a P2300 is stored, the cause should be diagnosed as soon as possible. The symptoms that likely accompany these codes will generally require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2300 trouble code may include:

• Engine misfires
• Decreased engine performance
• Reduced fuel efficiency
• Other related codes
• Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some common causes of the code?

Causes

of this code may include:

• Faulty relay or blown fuse (fuse link)
• PCM failure
• Open or shorted wiring or wiring connectors (damage from wildlife)
• Faulty ignition coil
• Faulty camshaft or crankshaft sensor or wiring

What are the troubleshooting steps for P2300?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P2300 code.

You can save yourself time and trouble by searching for Technical Service Bulletins (TSBs) that match the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P2300 to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout charts, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and vehicle in question) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace wiring that has been cut, burned, or damaged. Wiring on top of the engine is often damaged by wildlife trying to stay warm in cold climates.

Use the DVOM to test the voltage and ground circuits at the ignition coil in question. If no voltage is detected, check the system relay and associated fuses. Replace faulty relays and/or blown (or otherwise defective) fuses as needed.

If voltage and ground are detected at the coil, test the corresponding ground circuit at the PCM connector with the engine running. If a ground pulse is detected there, suspect an open circuit between the coil in question and the PCM. If no ground pulse is found there, suspect a faulty PCM or a programming error.

P2300 is frequently stored due to wiring damage caused by wildlife

How serious is this DTC?

When a P2301 is stored, the cause should be diagnosed as soon as possible. The symptoms that likely accompany these codes will generally require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2301 trouble code may include:

• Engine misfires
• Decreased engine performance
• Reduced fuel efficiency
• Other related codes
• Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some common causes of the code?

Causes

of this code may include:

• Faulty relay or blown fuse (fuse link)
• PCM failure
• Open or shorted wiring or wiring connectors (damage caused by wildlife)
• Faulty ignition coil
• Defective camshaft or crankshaft sensor or wiring

What are the troubleshooting steps for P2301?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P2301 code.

You can save yourself time and trouble by searching for Technical Service Bulletins (TSBs) that match the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P2301 to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, continue with the diagnosis.

You can obtain connector face views, connector pinout diagrams, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and vehicle in question) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace wiring that has been cut, burned, or damaged. Wiring on top of the engine is often damaged by wildlife trying to stay warm in cold climates.

Use the DVOM to test the voltage and ground circuits at the ignition coil in question. If no voltage is detected, check the system relay and associated fuses. Replace faulty relays and/or blown (or otherwise defective) fuses as needed.

If voltage and ground are detected at the coil, test the ground circuit corresponding to the PCM connector with the engine running. If a ground pulse is detected there, suspect an open circuit between the coil in question and the PCM. If no ground pulse is found there, suspect a faulty PCM or a programming error.

P2301 is frequently stored due to wiring damage caused by wildlife

How severe is this DTC?

When a P2302 is stored, the cause must be diagnosed as soon as possible. The symptoms that likely accompany these codes will generally require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2302 trouble code may include:

• Engine misfires
• Decreased engine performance
• Reduced fuel efficiency
• Other related codes
• Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some common causes of the code?

Causes

of this code may include:

• Bad spark plug wire or boot
• Faulty relay or blown fuse (fuse link)
• Open or shorted wiring or wiring connectors (damage caused by wildlife)
• Faulty ignition coil
• Faulty camshaft or crankshaft sensor or wiring

What are the troubleshooting steps for P2302?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P2302 code.

You can save time and trouble by searching for Technical Service Bulletins (TSBs) that match the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P2302 to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout diagrams, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and vehicle in question) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace wiring that has been cut, burned, or damaged. Scheduled maintenance includes replacing spark plug wires and boots. If the vehicle in question is beyond the recommended maintenance interval for a tune-up, suspect bad ignition wires/boots as the cause of a stored P2302.

Spark plug boots that are torn, burned, or contaminated with fluid should be considered faulty. Access the junction between the ignition coil and the spark plug wire. Check for high-energy ignition (HEI) at the spark plug. If none is detected, disconnect the spark plug wire from the coil and see if there is HEI there. If there is HEI at the spark plug, suspect a faulty spark plug or a PCM error. If there is no HEI at the spark plug but it is strong at the coil, suspect a bad spark plug wire or boot. If there is no HEI at the coil, suspect a faulty coil. HEI must be tested (carefully) with the engine running.

P2302 can be repaired with a maintenance tune-up, but do your diagnostic work to ensure

Fault Severity
The P2303 code indicates a serious problem requiring prompt diagnosis. Associated symptoms typically require immediate intervention to prevent engine damage.

Common Symptoms

• Engine misfires

• Reduced performance

• Increased fuel consumption

• Other related fault codes

• Possible deactivation of the affected cylinder’s injector by the PCM

Main Causes

• Blown fuse or faulty relay

• PCM (Powertrain Control Module) failure

• Damaged wiring (cuts, short circuits, rodent damage)

• Faulty ignition coil

• Failed camshaft/crankshaft sensor or defective wiring

Diagnostic Procedure

Required Equipment:

• OBD2 scanner

• Digital multimeter (DVOM)

• Vehicle technical documentation

Key Steps:

1. Check for TSBs: Consult Technical Service Bulletins (TSB) corresponding to your vehicle (model, engine) and symptoms for known solutions.

2. Read Codes:

   • Connect the scanner and retrieve all fault codes and freeze frame data.

   • Record them before clearing.

   • Test drive the vehicle: if the code reappears, continue; if the PCM enters “preparation mode,” the fault is intermittent.

3. Inspect Wiring:

   • Visually check wiring harnesses and connectors (especially for rodent damage).

   • Repair cut, burned, or damaged wires.

4. Test Ignition Coil:

   • Check voltage and ground at the affected coil using the DVOM.

   • No voltage? Check relays and fuses; replace if faulty.

5. Check PCM Signal:

   • Test the ground circuit at the PCM connector (with engine running).

   • Signal detected? Look for a break between PCM and coil.

   • No signal? Suspect PCM failure or programming error.

Important Note:
Rodent damage to wiring is a common cause of P2303, particularly in cold climates.

How severe is this DTC?

When a P2304 is stored, the cause should be diagnosed as soon as possible. The symptoms that likely accompany these codes will generally require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2304 trouble code may include:

• Engine misfires
• Decreased engine performance
• Reduced fuel efficiency
• Other related codes
• Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some common causes of the code?

Causes of this code may include:

• Faulty relay or blown fuse (fuse link)
• PCM failure
• Open or shorted wiring or wiring connectors (wildlife damage)
• Faulty ignition coil
• Defective camshaft or crankshaft sensor or wiring

What are the P2304 troubleshooting steps?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P2304 code.

You can save yourself time and trouble by searching for Technical Service Bulletins (TSBs) that match the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P2304 to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout diagrams, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and vehicle in question) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace wiring that has been cut, burned, or damaged. Wiring on top of the engine is often damaged by wildlife trying to stay warm in cold climates.

Use the DVOM to test the voltage and ground circuits at the ignition coil in question. If no voltage is detected, check the system relay and associated fuses. Replace faulty relays and/or blown (or otherwise defective) fuses as needed.

If voltage and ground are detected at the coil, test the ground circuit corresponding to the PCM connector with the engine running. If a ground pulse is detected there, suspect an open circuit between the coil in question and the PCM. If no ground pulse is found there, suspect a faulty PCM or programming error.

P2304 is frequently stored due to wiring damage caused by wildlife

How severe is this DTC?

When a P2305 is stored, the cause should be diagnosed as soon as possible. The symptoms that likely accompany these codes will generally require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2305 fault code may include:

• Engine misfires
• Decreased engine performance
• Reduced fuel efficiency
• Other related codes
• Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some common causes of the code?

Causes

of this code may include:

• Bad spark plug wire or boot
• Faulty relay or blown fuse (fuse link)
• Open or shorted wiring or wiring connectors (damage from wildlife)
• Faulty ignition coil
• Faulty camshaft or crankshaft sensor or wiring

What are the troubleshooting steps for P2305?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P2305 code.

You can save time and trouble by searching for Technical Service Bulletins (TSBs) that match the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P2305 to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout diagrams, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and the vehicle in question) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace wiring that has been cut, burned, or damaged. Scheduled maintenance includes replacing spark plug wires and boots. If the vehicle in question is beyond the recommended maintenance interval for a tune-up, suspect bad ignition wires/boots as the cause of a stored P2305.

Spark plug boots that are torn, burned, or contaminated with fluid should be considered faulty. Access the junction between the ignition coil and the spark plug wire. Check for high-energy ignition (HEI) at the spark plug. If none is detected, disconnect the spark plug wire from the coil and see if there is HEI there. If there is HEI at the spark plug, suspect a faulty spark plug or a PCM error. If there is no HEI at the spark plug but it is strong at the coil, suspect a bad spark plug wire or boot. If there is no HEI at the coil, suspect a faulty coil. HEI should be tested (carefully) with the engine running.

• P2305 may be fixed by a maintenance tune-up, but do your diagnostic work to ensure

How serious is this DTC?

When a P2306 is stored, the cause should be diagnosed as soon as possible. The symptoms that likely accompany these codes will generally require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2306 trouble code may include:

• Engine misfires
• Decreased engine performance
• Reduced fuel efficiency
• Other related codes
• Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some common causes of the code?

Causes

of this code may include:

• Faulty relay or blown fuse (fuse link)
• PCM failure
• Open or shorted wiring or wiring connectors (damage caused by wildlife)
• Faulty ignition coil
• Faulty camshaft or crankshaft sensor or wiring

What are the troubleshooting steps for P2306?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P2306 code.

You can save time and trouble by searching for Technical Service Bulletins (TSBs) that match the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P2306 to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout diagrams, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and vehicle in question) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace any wiring that is cut, burned, or damaged. Wiring on top of the engine is often damaged by wildlife trying to stay warm in cold climates.

Use the DVOM to test the voltage and ground circuits at the ignition coil in question. If no voltage is detected, check the system relay and associated fuses. Replace faulty relays and/or blown (or otherwise defective) fuses as needed.

If voltage and ground are detected at the coil, test the ground circuit corresponding to the PCM connector with the engine running. If a ground pulse is detected there, suspect an open circuit between the coil in question and the PCM. If no ground pulse is found there, suspect a faulty PCM or a programming error.

How severe is this DTC?

When a P2307 is stored, the cause should be diagnosed as soon as possible. The symptoms that likely accompany these codes will generally require immediate attention.

What are some of the symptoms of the code?

Symptoms of a P2307 trouble code may include:

• Engine misfires
• Decreased engine performance
• Reduced fuel efficiency
• Other related codes
• Fuel injector operation for the affected cylinder may be disabled by the PCM

What are some common causes of the code?

Causes

of this code may include:

• Faulty relay or blown fuse (fuse link)
• PCM failure
• Open or shorted wiring or wiring connectors (damage caused by wildlife)
• Faulty ignition coil
• Defective camshaft or crankshaft sensor or wiring

What are the P2307 troubleshooting steps?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P2307 code.

You can save yourself time and trouble by searching for Technical Service Bulletins (TSBs) that match the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P2307 to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout diagrams, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the specific code and vehicle) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace any wiring that is cut, burned, or damaged. Wiring on top of the engine is often damaged by wildlife trying to stay warm in cold climates.

Use the DVOM to test the voltage and ground circuits at the ignition coil in question. If no voltage is detected, check the system relay and associated fuses. Replace faulty relays and/or blown (or otherwise defective) fuses as needed.

If voltage and ground are detected at the coil, test the corresponding ground circuit at the PCM connector with the engine running. If a ground pulse is detected there, suspect an open circuit between the coil in question and the PCM. If no ground pulse is found there, suspect a faulty PCM or a programming error.