Finding the door pinswitch circuit

The best places to find the door pinswitch wire are:

■At the pinswitch: When testing at the pinswitch, check the wire to ensure that it “sees” all the doors. Often, the passenger switch will cover all the doors even if the driver’s switch will not.

■At the domelight: This may not be your best choice if the vehicle has delayed domelight supervision, but it will work in vehicles with completely diode-isolated pinswitches.

Once you have determined the wire color, the easiest place to connect to the wire is often at the kick panel, at the windshield pillar, or in the running board. When an easy location is not available, running a wire to the dome- light itself is often the best solution.

How to find a door pinswitch 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 and the meter goes to zero with the door closed, you have located a trigger wire.

NOTE: Make sure the wire you use detects all the doors! Some newer vehicles lack standard-type pin- switches. The domelights in these vehicles are turned on when the door handle is lifted. These usually have a wire coming out of the door into the kick panel, which will provide a (-) trigger for all doors.

finding the starter wire

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 interrupt the starter at the same point you test it. Hiding your starter kill relay and connections is always recommended.