How to find a (+) parking light flash 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 parking light wire. Usually, the area near the headlight/parking light
switch is an excellent area to start, as is the kick panel.
4. Turn on the parking lights. If the meter shows (+)12V, turn off the parking lights and make sure it returns to zero.
5. If it does return to zero, turn the parking lights back on and, using the dash light dimmer control, turn the
brightness of the dash lights up and down. If the meter changes more than a volt when using the dimmer,
look for another wire. If it stays relatively close to (+)12V, you have found your parking light wire.
NOTE:
Vehicles that use a (-) signal from the switch to the factory relay may be interfaced directly.
(See H1/5 WHITE wire of Primary Harness (H1) Wire Connection Guide section.)
To test for a tachometer wire, a multimeter capable of testing AC voltage must be used. The tachometer wire will
usually show between 1V and 6V AC. In multi-coil ignition systems, the system can learn individual coil wires.
Individual coil wires in a multi-coil ignition system will register lower amounts of AC voltage. Also, if necessary,
the system can use a fuel injector control wire for engine speed sensing, which should show lower amounts of
AC voltage. Common locations for a tachometer wire are the ignition coil itself, the back of the gauges, engine
computers, and automatic transmission computers.
IMPORTANT!
Do not test tachometer wires using a test light or logic probe! The vehicle will be damaged.
How to find a tachometer wire with your multimeter:
1. Set to ACV or AC voltage (12V or 20V is fine).
2. Attach the (-) probe of the meter to chassis ground.
3. Start and run the vehicle.
4. Probe the wire you suspect of being the tachometer wire with the red probe of the meter.
5. If this is the correct wire the meter will read between 1V and 6V.
finding the tachometer wire
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© 2000 Directed Electronics, Inc.
