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Home >> Cadillac >> 2003 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 617 (Data Link Communication System) >> Diagnostic Information and Procedures >> DTC U2102: More Controllers On Bus Than Programmed >> Diagnostic Aids
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Diagnostic Aids

WARNING: This page is about a different car, the 2004 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

The most likely occurrence of this DTC being set is due to incorrect calibration files downloaded to the ECM, or an ECM installed in the vehicle without the reprogramming procedure having been performed.

DTC U2102

Step Action Yes No
1 Did you perform the Diagnostic System Check Engine Controls? Go to Step 2  Go to Diagnostic System Check - Engine Controls
2
  1. Reprogram the ECM with the correct calibration for the vehicle. Refer to Service Programming System (SPS) in Programming.
  2. Start the engine.
Does the DTC reset?		 Go to Step 3  Go to Step 4 
3
IMPORTANT: Perform the programming or set up procedure for the replaced control module if required.
Replace the ECM. Refer to Engine Control Module (ECM) Replacement .Did you complete the replacement?		 Go to Step 4  -
4
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC run and pass?		 Go to Step 5  Go to Step 2 
5 Observe the stored information, Capture Info, with a scan tool.
Does the scan tool display any DTCs that you have not diagnosed?		 Go to Diagnostic Trouble Code (DTC) List System OK
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