Severity Medium
U0502

Door Control Module C Data Fault

📅 Last reviewed: July 2026
What does the U0502 code mean?

The control module that manages communication (typically the BCM or gateway) has detected that data received from the Door Control Module C is invalid, out of range, or fails integrity checks (checksum/CRC). This indicates data corruption on the CAN/LIN bus or an internal processor failure in the transmitting module.

Medium
Severity
Variable
Typical Cost
Medium
Frequency

1. Commonly Affected Makes

This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.

2. Most Common Causes

3. Symptoms You Will Notice

4. Step-by-Step Diagnosis

1

Scan all modules for related codes and check communication status

2

Inspect wiring and connectors at Door Control Module C and gateway/BCM for damage or corrosion

3

Test battery voltage and charging system; check for voltage fluctuations

4

Verify software versions and perform module reprogramming if mismatch is found

5

If wiring and voltage are OK, replace Door Control Module C

5. Frequently Asked Questions

Is it safe to drive?

Yes, the vehicle is generally safe to drive, but door-related functions may not work properly. Have it diagnosed soon to avoid further issues.

How much does it cost to fix?

Diagnosis typically $100-$200. Repair costs range from $200 for a connector repair to $800+ for module replacement and programming.

6. Related Codes

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