What Does U1222 Mean?
General communication failure for interior lamp operational data (not specifically outage detection) on the SCP network. Indicates broader communication issues with interior lighting system control and status information.
Common Causes
40%
Body control module software corruption or internal failure
25%
Complete loss of SCP network communication due to bus short or open circuit
20%
Failed overhead console or interior lighting master control module
15%
Power supply failure to interior lighting control circuits
Diagnostic Steps
1
Step 1: Verify all interior lighting circuits have proper power and ground
2
Step 2: Check all interior lighting fuses and relays in fuse panel
3
Step 3: Test SCP network integrity between BCM and all interior lighting modules
4
Step 4: Inspect for water damage in overhead console and pillar areas where modules are located
5
Step 5: Attempt BCM reprogramming or software update if network communication is intact
Estimated Repair Cost
$100 - $500
Parts + labor, varies by vehicle and location
General communication failure for interior lamp operational data (not specifically outage detection) on the SCP network. Indicates broader communication issues with interior lighting system control and status information.
The most common cause of U1222 (SCP (J1850) Invalid or Missing Data for Interior Lamps) is: Body control module software corruption or internal failure
Typical repair costs for U1222 range from $100 to $500, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Interior lighting may not function automatically but typically can be operated manually. Does not affect vehicle safety or driveability.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U1222 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
Vehicle Communication Network / Interior Lighting System
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
