P2511

ECM/PCM Power Relay Sense Circuit Intermittent

Q: Is it safe to drive with P2511?

Not confidently — an intermittent power feed to the ECM can cause a sudden stall or a failure to restart. Have it checked soon.

Q: Can I just clear P2511?

It returns the next time the ECM sees its power drop out. Fix the relay or wiring rather than clearing it.

Computer power supply / main relay Generic OBD-II Medium

What it means

P2511 means the ECM has seen its power-relay sense signal cut in and out. This circuit lets the ECM confirm it is receiving steady power through the main relay, so an intermittent signal points to a failing relay, a corroded socket, or wiring trouble. Because it involves the ECM's own power feed, it can cause random stalling or a no-start, and should be diagnosed promptly.

Medium

Can I keep driving? Can cause intermittent stalling or a no-start because it affects the ECM's own power feed — get it checked promptly.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Intermittent stalling or no-start
ECM resetting or losing power briefly
Other unrelated-looking codes stored at the same time

Common causes

Most likely first

Worn or failing ECM/PCM power (main) relayLikely
Corroded or loose relay socket or connectorCommon
Open or shorted wiring on the relay-sense circuitCommon
Low or weak battery powerLess often
Faulty ECM (rare)Less often

How to diagnose & fix

Work through it in order

Check battery voltage and the ECM grounds first.
Inspect and swap the ECM/PCM power relay with a known-good one.
Check the relay socket and sense-wire connector for corrosion or looseness.
Wiggle-test the circuit while monitoring for dropouts.
Repair the sense-circuit wiring; consider the ECM only after everything else checks out.

FAQ

Quick answers

Is it safe to drive with P2511?+

Not confidently — an intermittent power feed to the ECM can cause a sudden stall or a failure to restart. Have it checked soon.

Can I just clear P2511?+

It returns the next time the ECM sees its power drop out. Fix the relay or wiring rather than clearing it.

Read & clear P2511 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX