The P0690 code is an OBD-II trouble code that indicates a high voltage signal in the ECM/PCM Power Relay Sense Circuit. This code signifies that the engine control module (PCM) has detected an abnormal voltage condition from the power relay.
What Does the P0690 Code Mean?
The P0690 code means that there is an issue with the power relay that supplies voltage to the PCM. The PCM relies on accurate voltage readings to function properly, and when it senses that the voltage is outside the expected range, it sets the P0690 code.
What Causes the P0690 Code?
- Powertrain Control Module (PCM) failure
- Powertrain Control Module (PCM) power relay failure
- Wiring issues, such as short circuits or open circuits
What Are the Symptoms of the P0690 Code?
- Engine may not start
- Hard or no start in cold weather
How Serious Is the P0690 Code?
This code is classified as urgent because it can lead to severe malfunctions, including the inability to start the vehicle. Delaying repairs can cause further damage to the vehicle’s electrical system or the PCM itself.
How to Diagnose the P0690 Code
- Use an OBD-II scanner to confirm the P0690 code and check for any additional codes.
- Inspect the power relay and wiring related to the PCM for damage or corrosion.
- Test the voltage supply to the PCM to ensure it is within specifications.
- Check the PCM for any signs of failure or irregularities.
Common Repairs for the P0690 Code
- Replacing a faulty PCM
- Replacing the power relay
- Repairing or replacing damaged wiring
How Much Does It Cost to Fix the P0690 Code?
The cost to fix the P0690 code can vary widely depending on the underlying cause. Basic repairs like replacing a relay may cost $50 to $150, while PCM replacement can range from $300 to $1,500, including labor.
Can I Fix the P0690 Code Myself?
While some aspects of diagnosing and repairing the P0690 code can be done by a knowledgeable DIYer, it is recommended to consult with a professional mechanic for accurate diagnosis and repair, especially if PCM replacement is needed.
