LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> GMC >> 2002 >> Jimmy 2D Utility, Part Time, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 1658 (Cellular Communication System) >> Diagnostic Information and Procedures >> OnStar Button LED Inoperative >> Test Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test Description

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 GMC Yukon XL, 2002 GMC Yukon, 2002 Chevrolet Tahoe, 2002 Chevrolet Suburban, and 2002 Cadillac Escalade EXT. However, it is still accessible from the selected car via links, so may be relevant.

This procedure is for diagnosing problems with the OnStar® button assembly. The following numbers refer to the steps in the table.

  1. 3:  Determines if the OnStar® status LED has the necessary GRN LED signal circuit.
  2. 5:  If the GRN LED signal is shorted to voltage then the OnStar® three button assembly has been damaged. The OnStar® three button assembly has to be replaced.
OnStar Button LED Inoperative

Step Action Value(s) Yes No
Schematic Reference: OnStar Schematics 
1 Did you perform the Cellular Communications Diagnostic System Check? - Go to Step 2  Go to Diagnostic System Check - Cellular Communication 
2
  1. Turn the ignition ON, with ignition OFF.
  2. Observe the OnStar® status LED.
Did the OnStar® status LED turn GREEN?		 - Go to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS Go to Step 3 
3 
  1. Turn the ignition OFF.
  2. Disconnect the OnStar® button assembly connector.
  3. Turn the ignition ON, with ignition OFF.
  4. Measure the Keypad GRN LED signal circuit voltage.
Does the voltage measure near the specified value?		 7-9 V Go to Step 6  Go to Step 4 
4 Test the keypad GRN LED signal circuit for an open, high resistance or a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS .
Did you find and correct the condition?		 - Go to Step 10  Go to Step 5 
5  Test the keypad GRN LED signal circuit for an short to voltage. Refer to CIRCUIT TESTING and WIRING REPAIRS .
Did you find and correct the condition?		 - Go to Step 7  Go to Step 8 
6 Inspect for poor connections at the harness connector of the OnStar® button assembly. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS .
Did you find and correct the condition?		 - Go to Step 10  Go to Step 7 
7 Replace the OnStar® button assembly. Refer to OnStar Button Assembly Replacement (Utility) .
Did you complete the repair?		 - Go to Step 10  -
8 Inspect for poor connections at the harness connector of the VIU. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS .
Did you find and correct the condition?		 - Go to Step 10  Go to Step 9 
9
IMPORTANT: Perform the OnStar® setup procedure.
Replace the vehicle interface unit (VIU). Refer to OnStar Vehicle Interface Unit (VIU) Replacement .Did you complete the repair?		 - Go to Step 10  -
10 Operate the system in order to verify the repair.
Did you correct the condition?		 - System OK Go to Step 2 
scientia non olet · About LEMON Manuals