Onstar Button Stuck

B2482

OnStar Button Stuck







IMPORTANT: Before work begins, contact and inform the OnStar Call Centre (OCC) that a service is to be carried out on the unit.

Fault symptoms
- The LED on the control button unit shows a red light.
- It is not possible to ring to the OnStar Call Center (OCC).

On-Board Diagnosis

Type of diagnosis:
- Continuous

Enabling criteria:
- Ignition ON.
- The battery voltage must be 9.5 - 15.5 V
- The above conditions are fulfilled for more than 15 s.

Fault criteria:
- The control module detects that one of the buttons has stuck or has been depressed for more than 15 s.

Checking the wiring harness
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. Check switches, connectors and crimp connections for oxidation, withdrawn pins and pin clamping force.

Diagnostic help
The present fault code is erased directly the fault ceases. The historical fault codes are erased after 50 fault free driving cycles.

The control button unit incorporates three resistors connected in series which are supplied with 10 V from the VCIM. When a button is depressed the related resistor (button) is grounded and so generates the specific voltage/signal.

- Emergency 2.8 V
- OnStar Services 1.6V
- White Dot 0.45 V

Diagnostics applies to
Electrical fault in the connecting leads or in the control button unit.

Fault Diagnosis Procedure (2005;2006;2007;2008;2009;2010)