GM Service Manual Online
For 1990-2009 cars only

Object Number: 377171  Size: MF
Transfer Case Control Components
Transfer Case Control Schematics

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step determines if the transfer case shift control module has electronic control of the Service Indicator.

  2. This step determines if there is an internal short to ground in the transfer case shift control module.

  3. This step determines if CKT 1567 is shorted to ground.

Service Indicator Stays On When Key Is On

Step

Action

Value(s)

Yes

No

1

Was the Transfer Case Diagnostic System Check performed?

--

Go to Step 2

Go to Transfer Case Diagnostic System Check

2

  1. Connect the Scan Tool .
  2. Turn the ignition to RUN, engine OFF.
  3. Use the Scan Tool in order to command the Service Indicator OFF.

Does the Service Indicator turn OFF?

--

Go to Step 7

Go to Step 3

3

Disconnect both connectors at the transfer case shift control module.

Does the Service Indicator turn Off?

--

Go to Step 7

Go to Step 4

4

  1. Disconnect the connector at the Instrument cluster.
  2. Connect the J 39200 Digital Multimeter (DMM) and measure the resistance between the Instrument Cluster harness connector terminal A14 and ground.

Is the resistance within the specified value?

OL

Go to Step 5

Go to Step 6

5

Service instrument cluster for short to ground condition.

Is the action complete?

--

Go to Step 8

--

6

Repair a short to ground in CKT 1567. Refer to Wiring Repairs in Wiring System.

Is the repair complete?

--

Go to Step 8

--

7

Replace the transfer case shift control module. Refer to Tranfer Case Shift Control Module replacement. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

Go to Step 8

--

8

  1. Ensure the ignition is OFF.
  2. Properly mount and reconnect all previously disconnected ATC components.

Have all the ATC components been reconnected and properly mounted?

--

Go to Step 9

--

9

Clear all ATC DTCs.

Have all the ATC DTCs been cleared?

--

Go to Transfer Case Diagnostic System Check

--