Diagnosis And Testing - Microphone
To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbags, airbag curtains, knee blocker, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect the Intelligent Battery Sensor (IBS)/negative battery cable assembly from the negative battery post, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.
The hard wired inputs and outputs of the microphones in the inside rear view mirror may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the microphone or the electronic controls and communication between modules and other devices that provide some features of the Radio Receiver Module (RRM) controlled microphones. The most reliable, efficient and accurate means to diagnose the RRM or the electronic controls and communication related to RRM-controlled microphone operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.