P123A – BMW DTC

BMW DTC P123A – Brake Booster Pump Current High

DTC P123A meaning on BMW

DTC P123A on a BMW refers to a fault with the Brake Booster Pump Current being too high. This diagnostic trouble code indicates that the current flowing through the brake booster pump motor exceeds the predetermined threshold set by the vehicle’s engine control module (ECM).

BMW DTC P123A symptoms

Symptoms of DTC P123A on a BMW may include:

• Illuminated Check Engine Light (CEL)
• Decreased brake assist performance
• Unusual noises coming from the brake booster pump

BMW DTC P123A causes

The common causes of DTC P123A on a BMW include:

• Faulty brake booster pump motor
• Wiring or connection issues in the brake booster pump circuit
• ECM software or hardware problems

BMW DTC P123A seriousness

DTC P123A should not be ignored as it can affect the proper functioning of the brake booster system in your BMW. Reduced brake assist performance can compromise the safety of the vehicle and its occupants, so it is important to address this issue promptly.

How to diagnose DTC P123A on BMW

To diagnose DTC P123A on a BMW, you can follow these steps:

1. Use a diagnostic scanner to retrieve the fault codes stored in the ECM
2. Inspect the brake booster pump motor and its wiring for any visible damage or loose connections
3. Test the brake booster pump motor’s current draw using a multimeter to verify if it exceeds the specified limits

How to fix DTC P123A on BMW

To fix DTC P123A on a BMW, you may need to:

1. Replace the faulty brake booster pump motor
2. Repair any damaged wiring or connections in the brake booster pump circuit
3. Update the ECM software to the latest version if necessary

How to erase DTC P123A on BMW

To erase DTC P123A on a BMW, you can:

1. Use a diagnostic scanner to clear the fault codes stored in the ECM
2. After making the necessary repairs, 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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