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. |
| • | 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. |
