P2158

Vehicle Speed Sensor B Circuit

Q: Is it safe to drive with P2158?

Mechanically the engine is fine, but a lost speed signal can disable cruise control and confuse the transmission and ABS/traction systems, so drive carefully and repair it soon.

Q: Can I just clear P2158?

It will clear, but if the sensor or its wiring is faulty the code and the driveability symptoms will return.

Vehicle speed & idle control Generic OBD-II Medium

What it means

P2158 means the ECM has a problem with the 'B' vehicle speed sensor circuit — the signal that tells the car how fast it's moving. Many systems rely on this input, so a fault can throw off the speedometer, cruise control, automatic shifting, and traction/ABS aids. It's usually a failing speed sensor, a wiring or connector fault, or a damaged tone ring.

Medium

Can I keep driving? Drivable, but the speedometer, cruise control, and automatic shifting may misbehave and traction/ABS aids can drop out; fix it soon for safe operation.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

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
Inaccurate or dead speedometer
Harsh, erratic, or delayed automatic transmission shifts
Cruise control won't engage

Common causes

Most likely first

Faulty vehicle speed sensor (the 'B' sensor)Likely
Speed sensor harness open, shorted, or chafedCommon
Poor connection or corrosion at the speed sensor connectorCommon
Damaged reluctor/tone ring the sensor readsLess often

How to diagnose & fix

Work through it in order

Read freeze-frame data and check for the companion code P2159 or ABS/transmission codes.
Inspect the speed sensor connector and wiring for damage, corrosion, or a loose pin.
Check the sensor tip and the tone/reluctor ring for debris or damage.
Measure the sensor's signal and reference/ground circuits against spec.
Replace the vehicle speed sensor if it fails testing; verify the speedometer reads correctly afterward.

FAQ

Quick answers

Is it safe to drive with P2158?+

Mechanically the engine is fine, but a lost speed signal can disable cruise control and confuse the transmission and ABS/traction systems, so drive carefully and repair it soon.

Can I just clear P2158?+

It will clear, but if the sensor or its wiring is faulty the code and the driveability symptoms will return.

Read & clear P2158 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