Engine

P0375 — Timing Reference High Resolution Signal B Malfunction

Severity: high Drive with care, to a shop

What P0375 means

The engine control module uses crankshaft and camshaft position sensors to know engine position and speed, and it uses that data to time spark and fuel injection. P0375 sets when the high resolution timing reference signal on circuit B is missing, erratic or does not match what the ECM expects. The usual culprits are the sensor, its wiring or the trigger wheel, though a timing misalignment can also cause it.

Symptoms

  • Check engine light on
  • Engine cranks but does not start, or starts hard
  • Rough idle or misfires
  • Hesitation or stumbling under acceleration
  • Stalling while driving or at a stop
  • Reduced power and erratic performance

Possible causes

  1. Failed crankshaft or camshaft position sensor (circuit B)
  2. Open, shorted or corroded wiring or connector at the sensor
  3. Damaged or dirty reluctor/trigger wheel, or metal debris on the sensor tip
  4. Timing misalignment from a jumped belt or stretched chain
  5. Loose sensor or incorrect air gap
  6. Electrical noise, weak battery or poor ground
  7. Faulty ECM (rare)

How to diagnose

  1. Scan all codes and freeze frame data, and note related crank or cam codes such as P0335 and P0340
  2. Inspect sensor B, its connector and harness for chafing, oil, corrosion and damaged locks
  3. Check that the sensor is secure and properly gapped, then remove it and inspect the tip for debris or damage
  4. Test sensor power, ground and signal wires with a multimeter against the factory wiring diagram
  5. View the sensor signal on a scope while cranking and while running
  6. Inspect the trigger wheel for damaged or missing teeth
  7. Verify cam and crank timing and the condition of the belt or chain
  8. If everything checks out, test battery condition and consider the ECM

Common fixes

  • Replace crankshaft or camshaft position sensor B
  • Repair or replace damaged wiring and connectors
  • Replace or clean the trigger wheel
  • Correct engine timing or replace the belt, chain and tensioners
  • Reflash or replace the ECM if confirmed faulty

Questions and answers

What does P0375 mean?

The engine control module is getting a bad high resolution timing reference signal on circuit B from a position sensor. It then has trouble tracking engine position, which can cause misfires and starting problems.

Can I drive with P0375?

It is best not to. The engine can stall at any time and may not restart, so limit driving to a short trip to a repair shop.

What most often causes P0375?

A failed crankshaft or camshaft position sensor, or damaged wiring and connectors at that sensor, are the most common causes. A damaged trigger wheel or off timing is less common.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.