Ok ive check for 12 volts at the isolation relay its there. I replace the relay with brand new one. matter of fact i ordered 2 just in case from ac delco. I checked for voltage at the other right and left relays and its there with theyre individual grounds. I unplugged the iso relay .With the headlight switch in the on position i jumped the yello wire to the pink wire the lights raise up. Then i turned the lights off i jump the white wire to the blue and the blue-white wire and they close. I then replaced the headlight switch with one for wells. still they wont come up with and one will go down with the switch. whats the deal? the only theing i havent checked is the wires where the headlight switch comes to. but the switch is turning on the lights and sending 12v to the white and yellow wires. what else to check.

 

Let's see:



Your jumpering the wires at the isolation relay emulated exactly what the relay should do. Replacing the light switch was probably unnecessary unless the power at the white and yellow wires did not alternate with the switch positions. Your diagnosis seems to indicate a failed isolation relay (again???), but you may want to perform ONE more check. Reconnect the wiring, relays, switches, etcetera until the circuit is back in factory configuration (whereupon is should work).

1. Since it evidently does not work in that mode, verify that there is no power on the white wire when the headlight switch is in the ON position.
2. If there is no power on the white wire with the headlight switch ON, backprobe the isolation relay connector and jumper the yellow wire to the pink wire. The light doors should open. If so, the relay has a problem.
3. If the light doors operate as expected when you jumper the wires with the relay in the circuit, and REMAIN open when remove the jumper, shut off the lights and see if they close.
4. Regardless of whether both headlight doors close, remove the relay and remove its cover. There should be a relatively large diode on the relay crimped between two sets of contacts. ALL actuator relay current is passed through that diode. If the relays (near each headlight) are failing, wet, carbon contaminated, or have wiring problems, this diode can burn out on the first actuation. My guess is that is what has happened to your system.

 

2 questions one how do u precisley open a relay. and what is the chance of 3 relays being bad?
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do anyone know where the fog light relay is located?