10 © 1999 Directed Electronics, Inc. Vista, CA
How to find a door pin switch trigger wire with your multimeter:
1. Set to DCV or DC voltage (12V or 20V is fine).
2. In most cars, fasten the (+) probe of your meter to (+)12V constant.
3. Probe the wire you suspect of being the door trigger wire. If the meter reads (+)12V when any door is opened,
you have found a trigger wire.
NOTE: Make sure the wire you use “sees” all the doors! Some newer GM vehicles lack standard-type
pin switches. The dome light in these vehicles is turned on when the door handle is lifted. These
usually have a blue/white or white wire coming out of the door into the kick panel which will
provide a (-) trigger for all doors. Some GM vehicles (some Cavaliers, Grand Ams, etc.) have a yellow
wire coming out of the door which provides a (+) door trigger.
How to find the (+)12V starter wire with your multimeter:
1. Set to DCV or DC voltage (12V or 20V is fine).
2. Attach the (-) probe of the meter to chassis ground.
3. Probe the wire you suspect of being the starter wire. The steering column
is an excellent place to find this wire. Remember you do not need to inter-
rupt the starter at the same point you test it. Hiding your starter kill relay
and connections is always recommended.
4. Turn the ignition key switch to the start position. Make sure the car is not
in gear! If your meter reads (+)12V, go to the next step. If it doesn’t, probe
another wire.
5. Cut the wire you suspect of being the starter wire.
6. Attempt to start the car. If the starter engages, reconnect it and go back
to step 3. If the starter does not turn over, you have the right wire.
finding a starter wire