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Home >> Hummer >> 2009 >> H3 Base, Automatic >> Repair and Diagnosis >> Transmission >> Transfer Case >> Diagnostic Information and Procedures >> Transfer Case Shift Control Switch Indicator Always On - Two or More >> Test Description
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Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  This step tests the transfer case electrical control of the lamp circuits.
  2. 3:  This step tests the suspect lamp circuits for a short to ground.
Step Action Yes No
Schematic Reference: Transfer Case Control Schematics 
Connector End View Reference: Component Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? Go to Step 2  Go to Diagnostic System Check - Vehicle
  1. Turn the ignition ON, with the engine OFF.
  2. Install a scan tool.
  3. Use the scan tool in order to command all the indicator lamps OFF.
Do all the lamps go OFF?
Go to Step 7  Go to Step 3 
  1. Use the scan tool in order to determine the transfer case mode.
  2. Use this information to determine which lamp circuits are at fault.
  3. Disconnect the mode switch.
  4. Test the suspect lamp circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs .
Is the suspect circuit shorted to ground?
Go to Step 4  Go to Step 6 
4
  1. Disconnect the transfer case shift control module.
  2. Test the suspect lamp circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs .
Is the suspect circuit shorted to ground?
Go to Step 5  Go to Step 7 
5 Repair short to ground in the suspect lamp circuit. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
Go to Step 8  -
6 Replace the mode switch. Refer to Transfer Case Shift Control Switch Replacement .
Is the repair complete?
Go to Step 8  -
7 Replace the transfer case shift control module. Refer to Control Module References for replacement, setup and programming.
Is the repair complete?
Go to Step 8  -
8
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle in order to determine if the symptom has been corrected.
Is the symptom still present?
Go to Step 2  System OK