P06B1
Sensor Power Supply A Circuit Low
Sensor power supply (ECM)
Generic OBD-II
High
What it means
P06B1 means the ECM detected low voltage on its "A" sensor power-supply circuit — the regulated feed that powers a group of engine sensors. When that supply sags, the sensors on it read wrong together, which can make the engine run poorly, drop into limp mode, or set several related codes at once.
High
Can I keep driving? Drive with caution — a low sensor supply can affect several sensors at once, causing poor running or limp mode; get it diagnosed promptly.
Common symptoms
What you'll notice
- Check-engine light on, often with several sensor codes set at once
- Reduced power or limp mode
- Rough idle, hesitation, or surging
- Possible stalling
Common causes
Most likely first
- Short to ground, or an overload, on the sensor power-supply A circuitLikely
- A shorted sensor pulling the shared supply voltage downCommon
- Damaged wiring or a corroded/loose connector on the supply circuitCommon
- Faulty ECM/PCM sensor-supply outputLess often
How to diagnose & fix
Work through it in order
- Scan for all stored codes — the sensors sharing supply A help pinpoint the circuit.
- Inspect the supply wiring and connectors for shorts to ground and corrosion.
- With the key on, measure the supply voltage at the affected sensor connectors and compare to spec.
- Unplug sensors on that circuit one at a time to find one shorting the supply down.
- Only after wiring and sensors check out, consider a faulty ECM/PCM. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P06B1?+
Not for long — the supply feeds multiple sensors, so the engine can run poorly or drop into limp mode. Have it diagnosed before extended driving.
Can I just clear P06B1?+
It returns quickly because the supply circuit is still faulty. Clearing won't restore the sensors that depend on it.
Related codes
Often seen with P06B1
Read & clear P06B1 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