P1B90 – BMW DTC

BMW DTC P1B90 – 14 Volt Power Module System Voltage, Current High

DTC P1B90 meaning on BMW

The DTC P1B90 fault code on BMW vehicles indicates a problem with the 14 Volt Power Module System Voltage, Current being too high. This code is specific to BMW vehicles and is related to the power module system’s voltage and current levels exceeding the specified parameters.

BMW DTC P1B90 symptoms

Symptoms of the BMW DTC P1B90 code may include:

• Check Engine Light (MIL) illuminated on the dashboard
• Reduced electrical system performance
• Issues with starting the vehicle
• Electrical malfunctions

BMW DTC P1B90 causes

Common causes of the BMW DTC P1B90 fault code include:

• Faulty 14 Volt Power Module
• Short circuits in the power module system
• Overloaded electrical system
• Issues with the alternator or voltage regulator

BMW DTC P1B90 seriousness

The BMW DTC P1B90 fault code should be addressed promptly to prevent potential damage to the vehicle’s electrical system. Ignoring this fault code may lead to further electrical issues and could potentially leave the vehicle inoperable.

How to diagnose DTC P1B90 on BMW

To diagnose the DTC P1B90 code on a BMW, a mechanic will typically perform the following steps:

1. Use a diagnostic scanner to retrieve the fault codes stored in the vehicle’s computer
2. Inspect the 14 Volt Power Module for any visible damage or signs of malfunction
3. Check the wiring and connections in the power module system for any shorts or loose connections
4. Test the alternator and voltage regulator for proper operation

How to fix DTC P1B90 on BMW

To fix the DTC P1B90 fault code on a BMW, the following steps may be taken:

1. Replace the faulty 14 Volt Power Module if necessary
2. Repair any short circuits or damaged wiring in the power module system
3. Address any issues with the alternator or voltage regulator
4. Clear the fault codes using a diagnostic scanner after the repairs have been completed

How to erase DTC P1B90 on BMW

To erase the DTC P1B90 fault code on a BMW, follow these steps:

1. Connect a diagnostic scanner to the vehicle’s OBD-II port
2. Access the scanner’s menu and select the option to clear fault codes
3. Follow the on-screen prompts to erase the DTC P1B90 code from the vehicle’s computer
4. Once the code has been cleared, start the vehicle to ensure the Check Engine Light is no longer illuminated

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

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.