B0686 HUMMER – Security System Indicator Circuit Range/Performance

B0686 HUMMER Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

B0686 HUMMER Possible Causes

Faulty Instrument Panel Cluster (IPC),Instrument Panel Cluster (IPC) harness is open or shorted,Instrument Panel Cluster (IPC) circuit poor electrical connection,Faulty Body Control Module (BCM)

B0686 HUMMER Description

The security indicator is controlled by the Body Control Module (BCM) based on commands from the immobilizer system or the Content Theft Deterrent (CTD) system. With the ignition OFF, the security indicator is commanded by the CTD system. With the ignition ON, the security indicator is commanded by the immobilizer system. The security indicator is located in the Instrument Panel Cluster (IPC) and is supplied B+ at all times. When the immobilizer or CTD system requests the indicator be commanded ON, the BCM grounds the security indicator control circuit, illuminating the indicator.