P0371

Timing Reference High Resolution Signal A Too Many Pulses

Ignition / engine position Generic OBD-II High

What it means

P0371 means the ECM is counting more pulses than expected on the "A" high-resolution timing reference signal. This signal, generated by the crank/cam sensing system, tells the computer exactly where the engine is in its cycle. Too many pulses throws off timing, which can cause misfires, rough running, and hard starting until the sensor or reluctor is repaired.

High

Can I keep driving? Can be unpredictable — the ECM relies on this timing signal, so the engine may misfire, stall, or become hard to start. Have it diagnosed before depending on the car.

Real-world scan data

Seen in

635

scans in the past year

Found in

0.1%

of scans

0.2%

of scans that found faults

Appears alongside · share of P0371 scans

P1646in 88.2% of scans

P0704in 50.5% of scans

P1605in 44.4% 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
Engine misfires or runs rough
Hesitation, stumbling, or reduced power
Hard starting or intermittent stalling

Common causes

Most likely first

Faulty high-resolution timing reference sensorLikely
Damaged crankshaft or camshaft sensor or its wiringCommon
Damaged crank/cam reluctor ring or tone wheelCommon
Electrical interference or a poor ground on the signal circuitLess often
ECM fault (rare)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data and check for related crank/cam sensor codes.
Inspect the reference sensor connector and wiring for damage or corrosion.
Check the signal circuit for a solid ground and freedom from interference.
Inspect the reluctor ring/tone wheel for chipped or damaged teeth.
Replace the high-resolution reference sensor if it tests faulty; clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0371?+

Not ideal. A faulty timing reference can cause sudden misfires or stalling, so it's best diagnosed before you rely on the vehicle.

Can I just clear P0371?+

It returns as soon as the ECM sees the extra pulses again. The sensor or reluctor problem must be repaired first.

Read & clear P0371 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