Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with a part that helps control the fuel system. It's like a light switch that isn't working properly, and it might cause the car to not run as smoothly as it should.
The code indicates an issue with the power relay sense circuit in the Air Fuel Control Module (AFCM), suggesting that the voltage is higher than expected.
The P2A37 code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the AFCM power relay sense circuit. This circuit is responsible for monitoring the power relay that supplies voltage to the AFCM, which is crucial for proper air-fuel mixture control. A high voltage reading could indicate a short circuit, a faulty relay, or wiring issues.
• Check Engine Light illuminated
• Poor fuel economy
• Rough idling
• Engine hesitation or stalling
• Faulty AFCM power relay
• Short circuit in the wiring
• Defective ECM
• Corroded or damaged connectors
AFCM: Air Fuel Control Module
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the AFCM power relay and its connections.
• Check the wiring for any signs of damage or corrosion.
• Test the ECM for proper operation.
• Replace the AFCM power relay if it is faulty.
• Repair or replace damaged wiring and connectors.
• Reset the ECM and clear the code.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance checks
• Ensure proper electrical connections
• Keep the engine bay clean to prevent corrosion
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid driving long distances until the issue is resolved.
Check with the vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has been associated with vehicles that have experienced electrical issues in the AFCM circuit due to poor maintenance or environmental factors.
Moderate – The vehicle may continue to operate but with reduced performance and efficiency.
Ignoring this code can lead to increased emissions and potential engine damage. It is important to address it promptly.
• Engine running
• Electrical system under load
The AFCM power relay is typically located in the engine compartment, near the fuse box or ECM.
Q: Can I drive with a P2A37 code?
A: It's possible to drive short distances, but it's not recommended as it can lead to further engine issues.
Q: How can I prevent this code from appearing again?
A: Regular maintenance and inspections of the vehicle's electrical system can help prevent this issue.
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