What Does U1078 Mean?
Another SCP network communication fault indicating a third module is not transmitting valid data on the J1850 bus. Each U10XX code typically references a different module's Primary ID.
Common Causes
35%
Defective module unable to communicate on network
30%
Broken or shorted SCP bus wiring
20%
Insufficient power or ground to affected module
10%
Module connector pins damaged or pushed back
5%
Software/firmware corruption in module requiring reprogramming
Diagnostic Steps
1
Step 1: Verify adequate battery voltage and all power distribution fuses
2
Step 2: Identify the specific module associated with this Primary ID using manufacturer documentation
3
Step 3: Inspect module connector for bent pins, corrosion, or moisture
4
Step 4: Test power and ground circuits at module connector with DVOM
5
Step 5: Monitor SCP bus signals with oscilloscope to verify proper waveform characteristics
Estimated Repair Cost
$150 - $850
Parts + labor, varies by vehicle and location
Another SCP network communication fault indicating a third module is not transmitting valid data on the J1850 bus. Each U10XX code typically references a different module's Primary ID.
The most common cause of U1078 (SCP (J1850) Invalid or Missing Data for Primary Id) is: Defective module unable to communicate on network
Typical repair costs for U1078 range from $150 to $850, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Loss of module function may affect vehicle operation, comfort features, or safety systems. Severity depends on which specific module is affected.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U1078 to identify the root cause.
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Quick Info
Category
Network
System
Vehicle Communication Network
Difficulty
Type
Manufacturer
Recommended Tools
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