P0378
Timing Reference High Resolution Signal B Intermittent/Erratic Pulses
Generic code
Ignition System
High severity
Moderate repair
Free on OBD DashX
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What P0378 means
- The fault code P0378 indicates that intermittent pulses are detected in the high-resolution signal A that is used for timing reference. This may cause issues with engine timing and performance.
Possible symptoms
- Engine misfires
- Illuminated check engine light
Possible causes
- Faulty Timing Reference Optical Sensor
- Faulty camshaft sensor or associated circuit
- Faulty crankshaft sensor or the associated circuit
- Faulty crank and cam reluctor rings/ wheels
- Failed engine control module (ECM)
Related parts
- Timing Reference Optical Sensor: The optical sensor monitors the pulses in the fuel injection pump. More fuel is necessary to keep the engine running correctly in this case due to the malfunctioning optical sensor
Possible solutions
- Replace the high
- resolution signal A sensor
- Check and repair any damaged wiring or connections
- Tighten or clean any loose or corroded electrical connections
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0378 on OBD DashX
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