What Does U1219 Mean?
Additional communication error for external lamp data on SCP network, likely representing a fourth parameter or module in the lighting system network. May indicate widespread network communication degradation.
Common Causes
35%
Generic electronic module (GEM) or central junction box failure
30%
Multiple corroded connectors affecting several network nodes
20%
SCP network overload from excessive bus traffic or shorted module
15%
Damaged wiring harness from water intrusion or physical damage
Diagnostic Steps
1
Step 1: Identify all modules on SCP network and check which are not communicating using scan tool module scan
2
Step 2: Disconnect modules one at a time to isolate a potential shorted module pulling down network
3
Step 3: Inspect for water damage in module locations (under seats, kick panels, behind trim)
4
Step 4: Measure SCP bus resistance with all modules disconnected (should be infinite ohms to ground)
5
Step 5: Check for TSBs or software updates for affected modules
Estimated Repair Cost
$150 - $800
Parts + labor, varies by vehicle and location
Additional communication error for external lamp data on SCP network, likely representing a fourth parameter or module in the lighting system network. May indicate widespread network communication degradation.
The most common cause of U1219 (SCP (J1850) Invalid or Missing Data for External Lamps) is: Generic electronic module (GEM) or central junction box failure
Typical repair costs for U1219 range from $150 to $800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Network degradation may affect multiple vehicle systems beyond lighting. Ensure all safety-critical lights (brake lights, turn signals) are manually verified operational.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U1219 to identify the root cause.
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Quick Info
Category
Network
System
Vehicle Communication Network / Lighting System
Difficulty
Type
Manufacturer
Recommended Tools
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