GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2001 🢒 Bravada 🢒 Driveline/Axle 🢒 Transfer Case - NVG 136-NP4 (One Speed Automatic) 🢒 Service Indicator Always On

Service Indicator Always On for Oldsmobile Bravada 2001

Test Description

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

  1. Determines whether the failure is the result of a faulty transfer case shift control module or the instrument cluster.

Service Indicator Stays On When Key is On

Step

Action

Yes

No

Schematic Reference: Transfer Case Control Schematics

1

Did you perform the Transfer Case Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Transfer Case

2

  1. Turn the ignition ON, with the engine OFF.
  2. Install a scan tool.
  3. Use the scan tool in order to command the Service 4WD Lamp OFF.

Does the Service 4WD Lamp turn OFF?

Go to Step 3

Go to Diagnostic System Check - Instrument Cluster

3

Replace the transfer case shift control module. Refer to Transfer Case Shift Control Module Replacement .

Is the repair complete?

Go to Step 4

--

4
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for allowing the symptom to re-occur.

Does the symptom to re-occur?

Go to Step 2

System OK