P1551 – BMW DTC

BMW DTC P1551 – External Engine Off Timer Plausibility

DTC P1551 meaning on BMW

The Diagnostic Trouble Code (DTC) P1551 for BMW refers to the External Engine Off Timer Plausibility. This code indicates that there is an implausible signal or malfunction related to the external engine off timer system.

BMW DTC P1551 symptoms

Symptoms of DTC P1551 on a BMW may include:

• Check Engine Light (MIL) illuminated on the dashboard
• Engine may not shut off properly
• Reduced fuel efficiency

BMW DTC P1551 causes

Common causes of DTC P1551 on a BMW include:

• Defective external engine off timer sensor
• Wiring or connection issues in the external engine off timer circuit
• Faulty engine control module (ECM)

BMW DTC P1551 seriousness

While DTC P1551 may not cause immediate drivability issues, it is important to address this code promptly to prevent potential long-term damage to the engine or related components. Ignoring this code could lead to further complications and decreased performance.

How to diagnose DTC P1551 on BMW

To diagnose DTC P1551 on a BMW, follow these steps:

1. Use a diagnostic scanner to retrieve the fault codes stored in the ECM.
2. Inspect the external engine off timer sensor and its wiring for any visible damage or corrosion.
3. Perform a thorough inspection of the engine control module (ECM) and related components.

How to fix DTC P1551 on BMW

To fix DTC P1551 on a BMW, consider the following:

1. Replace the external engine off timer sensor if it is found to be faulty.
2. Repair any damaged wiring or connections in the external engine off timer circuit.
3. If the ECM is determined to be the issue, it may need to be reprogrammed or replaced.

How to erase DTC P1551 on BMW

To erase DTC P1551 on a BMW:

1. Use a diagnostic scanner to clear the fault codes stored in the ECM.
2. After clearing the codes, perform a test drive to ensure the issue has been resolved.

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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