P2507
ECM/PCM Power Input Signal Low
Engine control module power supply
Generic OBD-II
High
What it means
P2507 means the engine control module (ECM/PCM) is seeing low voltage on one of its power feeds. Because the computer needs steady power to run the engine, this fault can cause stalling, hard starting, or a no-start. It usually traces back to the battery, grounds, connectors, or power wiring rather than the ECM itself.
High
Can I keep driving? Drive with caution — low power to the engine computer can cause stalling, hard starting, or a no-start, and may leave you stranded if it worsens.
Common symptoms
What you'll notice
- Check-engine light on
- Hard starting, stalling, or intermittent no-start
- Rough running or driveability hiccups
- Other unrelated electrical codes may set at the same time
Common causes
Most likely first
- Weak or failing battery, or corroded/loose battery terminalsLikely
- Poor engine or chassis ground connectionCommon
- Corroded or loose ECM power/ground connectorCommon
- Open, shorted, or high-resistance wiring in the ECM power feedLess often
- Blown fuse or failing ECM power relayLess often
- Faulty ECM/PCM (least common)Less often
How to diagnose & fix
Work through it in order
- Load-test the battery and clean/tighten the battery terminals and grounds first.
- Read freeze-frame data to see the conditions when voltage dropped.
- Inspect the ECM power and ground circuits, fuses, and relay for corrosion or high resistance.
- Measure voltage at the ECM connector with the key on and while cranking — it should stay near battery voltage.
- Repair the wiring, ground, relay, or fuse as needed; replace the ECM only if power and grounds test good.
FAQ
Quick answers
Is it safe to drive with P2507?+
It can be risky — low voltage to the engine computer may cause stalling or a no-start. Have the battery, grounds, and power wiring checked before relying on the car.
Can I just clear P2507?+
It will return whenever the ECM sees low voltage again. Fix the power or ground fault first, then clear it.
Related codes
Often seen with P2507
Read & clear P2507 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX