ECM/PCM Power Relay Sense Circuit Intermittent
The P2511 code indicates that the Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected an intermittent signal from the power relay sense circuit. This circuit monitors the voltage output of the main relay that supplies power to the ECM/PCM. An intermittent fault means the signal is present sometimes but not consistently, often due to loose connections, corroded terminals, or a failing relay. This can cause erratic vehicle behavior and potential stalling.
01. Most Common Causes
- Faulty ECM/PCM power relay
- Corroded or loose relay socket terminals
- Damaged wiring or connectors in the relay sense circuit
- Intermittent short or open in the circuit
02. Symptoms You Will Notice
- Intermittent no-start condition
- Engine stalling or hesitation
- Check Engine Light illuminated
- Possible other electrical issues
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and document freeze frame data.
Step 2: Visually inspect the ECM/PCM power relay and its socket for corrosion, damage, or loose pins.
Step 3: Test relay operation by swapping with a known good relay and monitoring circuit continuity with a multimeter.
Step 4: Check wiring and connectors between the relay and ECM/PCM for breaks or intermittent shorts.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended because the intermittent power supply can cause sudden stalling or no-start conditions, posing a safety risk.
How much does it cost to fix?▼
Typically $50-$150 for parts and labor, depending on whether the relay or wiring needs replacement.