Checking Aftermarket Accessories

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, 2002 Chevrolet RV Cutaway, and 2002 Chevrolet Cutaway. However, it is still accessible from the selected car via links, so may be relevant.

Do not connect aftermarket accessories into the following circuits:

SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
WARNING: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. See DISABLING & ACTIVATING AIR BAG SYSTEM . Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs.
OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
CAUTION: The OBD II symbol is used on the circuit diagrams in order to alert the technician that the circuit is essential for proper OBD II emission control circuit operation. Any circuit which fails and causes the malfunction indicator lamp (MIL) to turn ON, or causes emissions-related component damage, is identified as an OBD II circuit.

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
Transceiver wiring located too close to vehicle electronic modules or wiring
Check for recent service bulletins detailing installation guidelines for aftermarket accessories.