Checking Aftermarket Accessories. Oldsmobile Shelby Series 1 1999

For 1990-2009 cars

Do not connect aftermarket accessories into the OBDII circuits, all such circuits are indicated on circuit diagrams with the OBDII 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.