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Home >> Cadillac >> 2006 >> STS Base, 3.6 7, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 3.6L - DTC P0700 To P2179 >> DTC P2105 >> Test Description
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Test Description

The number below refers to the step number on the diagnostic table.

  1. 2:  This step determines if the condition exists. If DTC P2105 sets, the engine will stall and not restart until the ignition is cycled OFF and then ON. Additional DTCs set when P2105 sets. The ignition key will not be able to be removed from the ignition switch until another ignition cycle occurs.
DTC P2105

Step Action Yes No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? Go to Step 2  Go to Diagnostic System Check - Vehicle
2 
  1. Turn ON the ignition, with the engine OFF.
  2. Clear the DTCs with a scan tool.
  3. Start the engine.
  4. Rapidly, move the accelerator pedal from the rest position to wide open throttle position. It may take a few attempts for the DTC to set.
  5. Observe the DTC information with a scan tool.
Does DTC P2105 fail this ignition?		 Go to Step 4  Go to Step 3 
3
  1. Observe the Freeze Frame/Failure records data for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure records data.
Did the DTC fail this ignition cycle?		 Go to Step 4  Go to Intermittent Conditions
4
IMPORTANT: The fuse must be removed to inspect for an open. Voltage will be available at both terminals at the fuse block, because of a normal voltage back feed condition.
Inspect the engine control module (ECM) or the HFV6 ECM fuse for being open.Is the fuse open?		 Go to Step 5  Go to Step 6 
5
    IMPORTANT: This DTC will only set if the fuse is open and the circuits are not grounded. The ignition 1 voltage circuits must be tested thoroughly for an intermittent short to ground.
  1. Test both ignition 1 voltage circuits between the fuse and the ECM for an intermittent short to ground. Refer to Circuit Testing and Wiring Repairs .
  2. Replace the fuse.
Did you find and correct the condition?		 Go to Step 9  Go to Intermittent Conditions
6 Test for an open ignition 1 voltage circuit between the ECM or the HFV6 ECM fuse and the splice. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 Go to Step 9  Go to Step 7 
7 Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?		 Go to Step 9  Go to Step 8 
8 Replace the ECM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?		 Go to Step 9  -
9
  1. Turn OFF the ignition for 30 seconds.
  2. Start the engine.
  3. Reset the fuel trim system with a scan tool.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition?		 Go to Step 2  Go to Step 10 
10 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 Go to Diagnostic Trouble Code (DTC) List - Vehicle System OK
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