P0652

Sensor Reference Voltage B Circuit Low

Q: Is it safe to drive with P0652?

Not ideal. Multiple sensors lose an accurate reference, so the engine can run poorly or stall. Get it diagnosed before longer trips.

Q: Can I just clear P0652?

It returns while the reference reads low. The usual cause is a short to ground or a shorted sensor — find that first.

Sensor reference / ECM Generic OBD-II High

What it means

P0652 means the ECM's 'B' 5-volt reference supply — the regulated voltage that feeds several sensors — is reading low, usually from a short to ground or a shorted sensor. Because multiple sensors share this reference, they can all report wrong values at once, making the engine run poorly, lose power, or stall. Trace the short rather than replacing sensors at random.

High

Can I keep driving? Have it diagnosed soon — the 'B' reference feeds several sensors, so the engine may run poorly, lose power, or stall when they read wrong.

Real-world scan data

Seen in

217

scans in the past year

Found in

<0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0652 scans

P0336in 52.5% of scans

P0113in 46.5% of scans

P0642in 34.1% of scans

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
Several sensor codes stored at once
Erratic or implausible sensor readings
Rough running, reduced power, or stalling

Common causes

Most likely first

Short to ground in the 'B' 5-volt reference circuitLikely
A shorted sensor pulling the shared reference downCommon
Damaged wiring or connector on the reference circuitCommon
Faulty ECMLess often

How to diagnose & fix

Work through it in order

Read all stored codes — several sensors sharing the 'B' reference will often flag together.
Disconnect sensors on the 'B' reference one at a time to find one shorting it low.
Inspect the reference wiring for a short to ground or chafing against the body.
Measure the reference voltage (should be near 5 V) at the sensors.
Replace the shorted sensor; if wiring and sensors are good, have the ECM tested. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0652?+

Not ideal. Multiple sensors lose an accurate reference, so the engine can run poorly or stall. Get it diagnosed before longer trips.

Can I just clear P0652?+

It returns while the reference reads low. The usual cause is a short to ground or a shorted sensor — find that first.

Read & clear P0652 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