What Does U0484 Mean?
The receiving control module is detecting corrupted or implausible data from Rear Lighting Control Module A on the vehicle network. This affects rear lighting functions including tail lights, brake lights, and turn signals.
Common Causes
35%
Faulty rear lighting control module A with internal circuit failure or water damage
25%
Damaged wiring or corroded connectors between rear lighting module and communication network
18%
Failed LED driver circuit or lamp out condition causing module data corruption
14%
Poor ground connection at rear lighting module or corroded bulkhead connector
8%
Module software corruption or configuration error after replacement
Diagnostic Steps
1
Step 1: Verify proper voltage supply and ground at rear lighting control module A connector
2
Step 2: Inspect rear lighting module and all associated connectors for corrosion, moisture, or physical damage
3
Step 3: Monitor rear lighting module data on scan tool to determine which parameters are reading as invalid
4
Step 4: Test all rear lighting circuits for proper load resistance and check for LED/bulb failures
5
Step 5: Check for software updates and perform module coding/adaptation; replace module if invalid data continues
Estimated Repair Cost
$200 - $850
Parts + labor, varies by vehicle and location
The receiving control module is detecting corrupted or implausible data from Rear Lighting Control Module A on the vehicle network. This affects rear lighting functions including tail lights, brake lights, and turn signals.
The most common cause of U0484 (Invalid Data Received From Lighting Control Module Rear "A") is: Faulty rear lighting control module A with internal circuit failure or water damage
Typical repair costs for U0484 range from $200 to $850, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Rear lighting may be inoperative or intermittent, making the vehicle difficult to see from behind and potentially preventing brake lights or turn signals from functioning. This creates significant rear-end collision risk.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U0484 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Network
System
Lighting System / Body Control
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
