P2511: ECM / PCM Power Relay Sense Circuit Intermittent — what it means, the affected system and what to check before replacing parts.
Meaning, symptoms, causes and checks
ECM/PCM power-relay feedback: The response is intermittent or unstable; a normal reading at another moment does not exclude the recorded condition. This is feedback from the power relay, not simply the command sent to it. Compare the controller-specific command and feedback interpretation; do not assume the entire module is defective.
Affected system: Engine/powertrain controller electrical supply
Symptoms
- Warning light may illuminate
- Related system function may be impaired
- Vehicle-specific symptoms vary
Possible causes
- Low or unstable supply voltage, fuse or relay fault, poor ground, or wiring damage
- Related wiring, connector, power or ground fault
- Vehicle-specific mechanical or control issue
What to check
- Record stored and pending codes and freeze-frame data
- Measure battery and charging voltage under load and compare with scan data; test the named circuit, fuse, relay, grounds and connectors.
- Confirm measured values against the vehicle service information
- Retest under the conditions that set the code
- Measure battery and charging voltage under load and compare with scan data; test the named circuit, fuse, relay, grounds and connectors.
- Repair the verified cause and confirm the code does not return
Also written as: P2511-00, P251100 (some scan tools add the fault-type byte, e.g. -00).