U1804 – BMW DTC

BMW DTC U1804 – Hybrid/EV Powertrain Control Module Lost Communication With HIM (Hybrid Interface Module) via HL-CAN

DTC U1804 meaning on BMW

The Diagnostic Trouble Code (DTC) U1804 for BMW indicates that there is a communication error between the Hybrid/EV Powertrain Control Module and the Hybrid Interface Module (HIM) via the HL-CAN (Hybrid Local Controller Area Network).

BMW DTC U1804 symptoms

Symptoms of the BMW DTC U1804 may include:

  • Check Engine Light (MIL) illuminated
  • Hybrid/EV system may not function properly
  • Loss of communication with the HIM

BMW DTC U1804 causes

Possible causes of the BMW DTC U1804 include:

  • Faulty Hybrid Interface Module (HIM)
  • Issues with the HL-CAN communication network
  • Wiring or connection problems

BMW DTC U1804 seriousness

The DTC U1804 on a BMW is considered serious as it can affect the proper functioning of the Hybrid/EV powertrain system. Ignoring this issue may lead to further complications and potential drivability problems.

How to diagnose DTC U1804 on BMW

To diagnose the DTC U1804 on a BMW, you can follow these steps:

  1. Use a diagnostic scanner to retrieve the fault codes
  2. Check the communication between the Hybrid/EV Powertrain Control Module and the HIM
  3. Inspect the wiring and connections related to the HL-CAN network
  4. Perform a visual inspection for any visible damage or loose connections

How to fix DTC U1804 on BMW

To fix the DTC U1804 on a BMW, you can try the following:

  1. Inspect and repair any damaged wiring or connections
  2. Replace the faulty Hybrid Interface Module (HIM) if necessary
  3. Clear the fault codes using a diagnostic scanner
  4. Perform a test drive to ensure the issue has been resolved

How to erase DTC U1804 on BMW

To erase the DTC U1804 on a BMW, you can use a diagnostic scanner to clear the fault codes. Follow these steps:

  1. Connect the diagnostic scanner to the vehicle’s OBD-II port
  2. Select the option to erase fault codes
  3. Confirm the action and wait for the process to complete
  4. Verify that the DTC U1804 has been successfully erased