P2510: ECM/PCM Power Relay Sense Circuit Range/Performance

What it means

The voltage reported on the main power relay sense line for the engine controller does not match expectation. The ECU may shut down too early or stay awake too long, draining the battery.

At a glance

• Usually lights the check-engine light

How it works

The ECM/PCM power relay supplies operating power to the engine controller, and its sense line lets the controller check the relay's output. P2510 sets when the reported sense voltage does not perform within the expected range, which can leave the controller without power or keep it awake after shutdown.

Common causes

Most likely first.

1. Faulty or worn power relay
2. Damaged or corroded relay sense wiring or connector

Symptoms

• Check-engine light
• Intermittent stalling or no-start
• Battery may drain while parked

How to diagnose it

1. Review freeze-frame data and note whether the code appeared during starting, driving, or after the vehicle was switched off.
2. Check battery condition and inspect the ECM/PCM power relay, fuse area, and relay connectors for heat damage, corrosion, or poor seating.
3. Use live data or a meter to compare the relay sense-line voltage with relay command and controller power states.
4. Inspect the sense wire and its connectors for corrosion, damage, or high resistance, then check power and ground feeds to the relay.
5. Test the relay's switching and sense output against the wiring diagram and manufacturer's specification.

Common fixes

• Reseat or clean a loose or corroded power-relay connector.
• Repair damaged or high-resistance relay sense wiring.
• Replace a worn ECM/PCM power relay if it fails the specified switching test.
• Repair a faulty relay power or ground connection confirmed by testing.

Can I keep driving?

Intermittent controller power can cause stalling or a no-start, so avoid long trips and stop somewhere safe if the engine cuts out. If the vehicle stays awake after shutdown, it may drain the battery while parked.