P0378 – BMW DTC

BMW DTC P0378 – Timing Reference High Resolution Signal ‘B’ Intermittent/Erratic Pulses

DTC P0378 meaning on BMW

DTC P0378 on a BMW indicates an issue with the Timing Reference High Resolution Signal ‘B’ having intermittent or erratic pulses. This signal is crucial for the engine control module to accurately determine the engine’s timing.

BMW DTC P0378 symptoms

Symptoms of DTC P0378 on a BMW may include:

• Engine misfires
• Reduced engine performance
• Difficulty starting the engine
• Illuminated check engine light

BMW DTC P0378 causes

Common causes of DTC P0378 on a BMW include:

• Faulty crankshaft position sensor
• Wiring issues in the timing reference signal circuit
• Corrosion or poor connections in the signal circuit
• Issues with the engine control module

BMW DTC P0378 seriousness

Ignoring DTC P0378 on a BMW can lead to potential engine performance issues and further damage. It is important to address this fault promptly to prevent any long-term problems.

How to diagnose DTC P0378 on BMW

To diagnose DTC P0378 on a BMW, a mechanic may perform the following steps:

1. Use a diagnostic scanner to retrieve the fault code and related data
2. Inspect the crankshaft position sensor and its wiring for any visible damage
3. Check the connections in the timing reference signal circuit for corrosion or poor contact
4. Perform a thorough inspection of the engine control module for any signs of malfunction

How to fix DTC P0378 on BMW

To fix DTC P0378 on a BMW, the following steps may be taken:

1. Replace the faulty crankshaft position sensor if necessary
2. Repair any damaged wiring in the timing reference signal circuit
3. Clean or replace any corroded connectors in the signal circuit
4. If the issue persists, consider testing or replacing the engine control module

How to erase DTC P0378 on BMW

After fixing the underlying issue causing DTC P0378 on a BMW, the fault code can be erased using a diagnostic scanner. This will clear the code from the engine control module’s memory and turn off the check engine light.

Recommended tools & DTC Scanners for BMW

Best Diagnostic App for modern BMWs: BimmerLink

Recommended Bluetooth adapter for Bimmerlink: OBDLink CX

Cable adapter for Bimmerlink: Enet Cable USB Type C

For older BMWs we recommend: Autel AutoLink AL319 (2024 version)

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

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