P0699

Sensor Reference Voltage C Circuit High

Q: Is it safe to drive with P0699?

Not ideally — because multiple sensors share this reference, the engine can run poorly or derate. Have it diagnosed promptly.

Q: Can I just clear P0699?

It returns until the shorted sensor or wiring is repaired. Because several sensors share the circuit, a scan tool is the fastest way to isolate the cause.

Sensor reference voltage Generic OBD-II High

What it means

P0699 means the ECM sees its "C" 5-volt sensor reference reading higher than expected. Many sensors — throttle, pedal, pressure, and others — share this regulated reference, so when it drifts high those sensors report wrong values and the engine can run poorly or drop into limp mode. The fault usually traces to one shorted sensor, a wiring short to voltage, or the ECM, rather than to the engine itself.

High

Can I keep driving? It can run rough or drop into limp mode, because several sensors share this 5-volt reference — get it diagnosed before relying on the vehicle.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Appears alongside · share of P0699 scans

P0193in 87.9% of scans

P0698in 87.9% of scans

P0192in 84.8% 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
Reduced power or limp mode
Several sensor codes stored at once (they share the same 5-volt reference)
Rough running, hesitation, or erratic gauges

Common causes

Most likely first

A sensor on the 5-volt reference C circuit shorted internally, pulling the reference highLikely
Reference wire shorted to battery or another voltage sourceCommon
Poor ECM ground or corroded connector affecting the referenceCommon
Faulty ECMLess often

How to diagnose & fix

Work through it in order

Scan and note every code present — the sensors sharing reference C help pinpoint the affected circuit.
Identify the sensors fed by the 5-volt reference C circuit for this vehicle, then unplug them one at a time to see if the reference voltage returns to normal — that isolates a shorted sensor.
Inspect the reference wiring and connectors for a short to voltage, and check the ECM grounds.
If the reference stays high with all sensors disconnected and wiring good, the ECM is at fault.

FAQ

Quick answers

Is it safe to drive with P0699?+

Not ideally — because multiple sensors share this reference, the engine can run poorly or derate. Have it diagnosed promptly.

Can I just clear P0699?+

It returns until the shorted sensor or wiring is repaired. Because several sensors share the circuit, a scan tool is the fastest way to isolate the cause.

Read & clear P0699 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