P0377
Timing Reference High Resolution Signal "B" Too Few Pulses
- Severity
- Medium
- Driving
- Drivable — book it in
The high-resolution timing reference signal "B" is producing too few pulses - the module is seeing fewer edges than it expects. A damaged or contaminated trigger wheel, or a sensor with too large an air gap, will do this.
Possible causes
- CommonFailed timing reference sensor
- CommonDamaged or contaminated trigger wheel
- CommonCorroded connector or damaged wiring
- PossibleMetal debris on the sensor tip
- PossibleInterference from a nearby high-voltage component
- PossibleStretched timing chain changing the signal relationship
What you might notice
- Rough running or misfire
- Reduced power
- Hard starting
- Check engine light on
- Poor fuel economy
What to check, in order
- Inspect the trigger wheel for a damaged or missing tooth, and check the sensor air gap if it is adjustable.
- Read all codes. Crankshaft and camshaft codes alongside these point at timing rather than at this sensor.
- Inspect the connector and wiring for corrosion, chafing and heat damage.
- Inspect the sensor tip for debris and the trigger wheel for damage.
- Check the harness routing. This is a fine-resolution signal and it is more vulnerable to interference than most, so a lead re-routed against an ignition component can cause it.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Ignition system or misfire
P0300P0301P0302P0303P0304P0305P0306P0307P0308P0309P0310P0311P0312P0313P0314P0315P0316P0317P0318P0319P0320P0321P0322P0323P0324P0325P0326P0327P0328P0329P0330P0331P0332P0333P0334P0335P0336P0337P0338P0339P0340P0341P0342P0343P0344P0345P0346P0347P0348P0349P0350P0351P0352P0353P0354P0355P0356P0357P0358P0359P0360P0361P0362P0363P0364P0365P0366P0367P0368P0369P0370P0371P0372P0373P0374P0375P0376P0377P0378P0379P0380P0381P0382P0383P0384P0385P0386P0387P0388P0389P0390P0391P0392P0393P0394