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Home >> Cadillac >> 2017 >> CT6 Plug-In >> Repair and Diagnosis >> Engine Performance >> System >> Data Communication System - DTC B1000 To DTC U1818 >> Diagnostic Information and Procedures >> DTC U179D: Lost Communication with Brake System Control Module 2 on Chassis Expansion Bus >> Diagnostic Fault Information
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Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
B+ U179D U179D - -
Ignition U179D U179D - -
Accessory Wake Up Serial Data 2 P06E4, U179D U179D - -
Chassis High Speed GMLAN Serial Data (+) U0077* U179D, U0077* U0077* -
Chassis High Speed GMLAN Serial Data (-) U0077* U179D, U0077* U0077* -
Ground - U179D - -
* Other DTCs may set with this fault.