The following numbers refer to the steps in the table.
Check for proper operation of the OnStar® Center Button.
Check for proper operation of the OnStar® Call Answer/Call End Button.
Check for proper operation of the OnStar® Emergency Button.
Determine OnStar® Button Assembly has the necessary power and signal circuits.
Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
DEFINITION: This procedure is for diagnosing problems with the OnStar® Button Assembly.  | ||||
1  | Did you perform the OnStar® Diagnostic System Check?  | --  | Go to Step 2  | Go to OnStar System Check  | 
2  | Did you check the Audio system for proper operation?  | --  | Go to Step 3  | |
 Does "Connecting to OnStar®" play through the audio system?  | --  | Go to Step 4  | Go to Step 6  | |
 Does "OnStar® Request Ended" play through the audio system?  | --  | Go to Step 5  | Go to Step 7  | |
 Does "Connecting to OnStar® Emergency" play through the audio system?  | --  | Go to Step 14  | Go to Step 8  | |
6  | 
 Does the resistance measure near the specified value?  | 3.0 Kohms  | Go to Step 9  | Go to Step 12  | 
7  | 
 Does the resistance measure near the specified value?  | 13 Kohms  | Go to Step 9  | Go to Step 12  | 
8  | 
 Does the resistance measure near the specified value?  | 1.5 Kohms  | Go to Step 9  | Go to Step 12  | 
Measure the voltage at the OnStar® Keypad between Keypad Power circuit and the Keypad Signal circuit. Does the voltage measure near the specified value?  | 3V  | Go to Step 13  | Go to Step 10  | |
10  | Test the Keypad Power circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the problem?  | --  | Go to Step 14  | Go to Step 11  | 
11  | Test the Keypad Signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the problem?  | --  | Go to Step 14  | Go to Step 13  | 
12  | Replace the OnStar® Three Button Assembly. Refer to OnStar Button Assembly Replacement . Did you complete the replacement?  | --  | Go to Step 14  | --  | 
13  | Replace the Vehicle Interface Unit (VIU). Refer to Vehicle Interface Unit and Vehicle Communication Unit Modules Replacement . Did you complete the replacement?  | --  | Go to Step 14  | --  | 
14  | Operate the system in order to verify the repair. Did you correct the condition?  | --  | System OK  | Go to Step 3  |