Chevrolet Equinox Service Manual: Checking Aftermarket Accessories

Warning:Refer toSIR Warning.

Caution:The OBD II symbol is used on the circuit diagrams in order toalert the technician that the circuit is essential for proper OBDII emission control circuit operation. Any circuit which fails andcauses the malfunction indicator lamp (MIL) to turn ON, or causesemissions-related component damage, is identified as an OBD IIcircuit.

Do not connect aftermarket accessories into the following circuits:

SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.OBD-II circuits, all such circuits are indicated on circuit diagrams with the OBD-IIsymbol.

Always check for aftermarket accessories (non-OEM) as the first step in diagnosingelectrical problems. If the vehicle is so equipped, disconnect the system to verifythat 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 batteryAntenna locationTransceiver wiring located too close to vehicle electronic modules or wiringPoor shielding or poor connectors on antenna feed lineCheck for recent service bulletins detailing installation guidelines for aftermarketaccessories.