U0165 – BMW DTC

BMW DTC U0165 – Lost Communication With HVAC Control Module (Rear)

DTC U0165 meaning on BMW

The DTC U0165 code on a BMW indicates a communication error between the vehicle’s main control module and the HVAC (Heating, Ventilation, and Air Conditioning) control module located in the rear of the vehicle. This error typically means that the main control module is unable to establish communication with the rear HVAC control module.

BMW DTC U0165 symptoms

Symptoms of the DTC U0165 code on a BMW may include:

• Malfunctioning rear HVAC system
• Inoperative rear climate controls
• Erratic behavior of the rear air conditioning or heating
• Dashboard warning light indicating a communication fault

BMW DTC U0165 causes

The common causes of the DTC U0165 code on a BMW are:

• Faulty rear HVAC control module
• Wiring or connection issues between the main control module and the rear HVAC module
• Defective main control module
• Software glitches or programming errors

BMW DTC U0165 seriousness

While the DTC U0165 code may not directly affect the drivability of the vehicle, it can lead to discomfort for passengers due to the malfunctioning rear HVAC system. It is recommended to address this issue promptly to ensure proper climate control functionality in the vehicle.

How to diagnose DTC U0165 on BMW

To diagnose the DTC U0165 code on a BMW, a mechanic would typically perform the following steps:

1. Use a diagnostic scanner to retrieve the specific fault codes stored in the vehicle’s system
2. Inspect the wiring and connections between the main control module and the rear HVAC module for any visible damage or corrosion
3. Test the rear HVAC control module for proper functionality
4. Check for any software updates or reprogramming needed for the control modules

How to fix DTC U0165 on BMW

To fix the DTC U0165 code on a BMW, the following steps can be taken:

1. Repair or replace any damaged wiring or connections between the main control module and the rear HVAC module
2. Replace the faulty rear HVAC control module if necessary
3. Update or reprogram the control modules with the latest software versions
4. Clear the fault codes using a diagnostic scanner after the repairs have been completed

How to erase DTC U0165 on BMW

To erase the DTC U0165 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 to clear the fault codes stored in the system
3. Follow the on-screen instructions to erase the DTC U0165 code
4. Verify that the code has been successfully cleared by rescanning the system

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.