Checking Aftermarket Accessories

Checking Aftermarket Accessories

Do not connect aftermarket accessories into the following circuits:

WARNING: Refer to [Restraint System Service Precautions].

^ SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.

CAUTION: Refer to OBD II Symbol Description Notice.

^ OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.

Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical problems. If the vehicle is so equipped, disconnect the system to verify that these add-on accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
^ Power feeds connected to points other than the battery
^ Antenna location
^ Transceiver wiring located too close to vehicle electronic modules or wiring
^ Poor shielding or poor connectors on antenna feed line
^ Check for recent service bulletins detailing installation guidelines for aftermarket accessories.