What Does U0502 Mean?
Door Control Module C (typically left rear door) is transmitting invalid or corrupted data over the vehicle network. Communication exists but the data values are outside normal parameters or contain errors.
Common Causes
35%
Defective door control module C with internal component failure
25%
Connector corrosion or terminal damage at rear door module connection
20%
Damaged CAN bus wiring in rear door or body harness
12%
Voltage drop or poor ground connection to rear door module
8%
Module configuration error or firmware incompatibility
Diagnostic Steps
1
Step 1: Test voltage supply and ground integrity at door control module C connector (should have stable 12V and <0.5V ground)
2
Step 2: Inspect rear door harness and connector for damage from repeated door movement or water leaks
3
Step 3: Use scan tool to monitor real-time data from Module C for erratic sensor readings or communication dropouts
4
Step 4: Verify CAN bus signal quality with oscilloscope if available; check for noise or improper voltage levels
5
Step 5: Attempt module reset/reprogramming; replace door control module C if invalid data continues after wiring verification
Estimated Repair Cost
$150 - $650
Parts + labor, varies by vehicle and location
Door Control Module C (typically left rear door) is transmitting invalid or corrupted data over the vehicle network. Communication exists but the data values are outside normal parameters or contain errors.
The most common cause of U0502 (Invalid Data Received From "Door Control Module C") is: Defective door control module C with internal component failure
Typical repair costs for U0502 range from $150 to $650, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Left rear door locks, windows, or child safety features may not function properly. Vehicle remains safe to operate but rear passenger convenience and security are affected.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U0502 to identify the root cause.
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Quick Info
Category
Network
System
Body Control Network / Door Control System
Difficulty
Type
Generic (SAE)
Recommended Tools
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