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DTC U1001 To U1254: Module U1XXX Communication: Notes

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
DTC U1001-U1254

Control Module ID Number
PCM 016
ECM 017
TCM 024
EBCM 040
BCM 064
SDM 088
IPC 096
HUD 098
Radio 128
VIU 146
HVAC 152
MSM 166
Theft Deterrent Control Module 192

When more than one Loss of Communication DTC is set in either one module or in several modules, diagnose the DTCs in the following order:

  1. Current DTCs before history DTCs unless told otherwise in the diagnostic tables.
  2. The DTC which is reported the most times.
  3. From the lowest number DTC to the highest number DTC.