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Home >> Chevrolet >> 2014 >> SS >> Repair and Diagnosis >> Engine Performance >> System >> Data Communication System >> Diagnostic Information and Procedures >> DTC U0074: Control Module Communication Bus >> Diagnostic Fault Information
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Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
Chassis High Speed GMLAN Serial Data (+) U0074 U0074, U0100-U02FF* U0074 -
Chassis High Speed GMLAN Serial Data (-) U0074 U0074, U0100-U02FF* U0074 -
Ground (DLC, terminal 5) - 1 - -
* An open between the data link connector (DLC) and the first splice/device will only affect the communication with the scan tool. The devices will still communicate. An open in only one chassis high speed GMLAN serial data circuit may allow degraded communication between the devices.
1. No communication with any chassis high speed GMLAN device.