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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 U1803: Lost Communication with Hybrid Powertrain Control Module 2 >> Diagnostic Fault Information
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Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
B+ U1803 U1803 - -
Ignition U1803 U1803 - -
Accessory Wakeup Serial Data U1814 U1803 - -
Low Speed GMLAN Serial Data 1 U1803 1 -
High Speed GMLAN Serial Data (+) 2 U1803, U0073 2 -
High Speed GMLAN Serial Data (-) 2 U1803, U0073 2 -
Powertrain High Speed GMLAN Serial Data (+) U0074 U1803, U0074 U0074 -
Powertrain High Speed GMLAN Serial Data (-) U0074 U1803, U0074 U0074 -
High Voltage Energy Management High Speed GMLAN Serial Data (+) U007A U1803, U007A U007A -
High Voltage Energy Management High Speed GMLAN Serial Data (-) U007A U1803, U007A U007A -
Ground - U1803 - -
1. Scan Tool Does Not Communicate With Low Speed GMLAN Device
2. Scan Tool Does Not Communicate With High Speed GMLAN Device