P3243 – BMW DTC

BMW DTC P3243 – CAN Timeout Electrical Auxiliary Heater

DTC P3243 meaning on BMW

DTC P3243 on a BMW indicates a CAN (Controller Area Network) timeout related to the electrical auxiliary heater system. This means that the communication between the control modules responsible for managing the auxiliary heater has been interrupted or lost.

BMW DTC P3243 symptoms

Symptoms of DTC P3243 on a BMW may include:

• Check Engine Light (MIL) illuminated
• Loss of auxiliary heater functionality
• Reduced heating performance in the vehicle

BMW DTC P3243 causes

Common causes of DTC P3243 on a BMW include:

• Faulty electrical connections related to the auxiliary heater system
• Defective auxiliary heater control module
• Interference or wiring issues in the CAN network

BMW DTC P3243 seriousness

While DTC P3243 may not directly affect the drivability of the vehicle, it can lead to discomfort for the occupants due to the loss of auxiliary heating functionality. It is recommended to address this issue to ensure proper operation of the auxiliary heater system.

How to diagnose DTC P3243 on BMW

To diagnose DTC P3243 on a BMW, a mechanic would typically perform the following steps:

1. Use a diagnostic scanner to retrieve the fault codes stored in the vehicle’s computer
2. Inspect the electrical connections and wiring related to the auxiliary heater system
3. Check the auxiliary heater control module for any signs of damage or malfunction
4. Perform a CAN network diagnosis to identify any communication issues

How to fix DTC P3243 on BMW

To fix DTC P3243 on a BMW, the following steps may be taken:

1. Repair or replace any faulty electrical connections related to the auxiliary heater system
2. Replace the defective auxiliary heater control module, if necessary
3. Address any wiring issues or interference in the CAN network

How to erase DTC P3243 on BMW

To erase DTC P3243 on a BMW, the fault codes can be cleared using a diagnostic scanner. After the necessary repairs have been made to address the underlying issue, the fault codes can be reset to turn off the Check Engine Light and ensure that the system is functioning properly.

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.