hey guys i am completely stumped and confused. im trying to understand how the circuitry works in my 87 for the head lights to go up and down. the problem im having is that with the different years of the car the system seems to be a little different so the information im gathering is confusing me. i found that my head light control module was burned to a crisp so i replaced it with a refurbished one from ebay. but now the headlights wont go up, they will only go down. i also can't figure out if there is an isolation relay on my car? i checked the two fuseable links and they are good to go. other than that i have no idea whats going on. any ideas please?

 

You might want to check your actual motors, to me: that's a sign that the internals dissolved like mine did. (If they're spinning but not going anywhere). Another problem I had with mine was the actual switch in the dash, the contacts inside were dirty/slightly corroded after 20+ years, so I had to push hard on the switch for the contact to be made.

 

the thing is both lights go down when i turn the switch off in the car. the switch is new, the modulator is new. i found a relay mounted next to the fan on the radiator on the passenger side..i can't figure out what it is. could this be the isolation relay? does the 87 firebird have an isolation relay??

 

There is no isolation relay, those were used on the 1982-96 3-wire motors. Your 1987 Firebird has the better 2-wire motor. You have a headlight control module instead. By your symptoms I'd say you have the wrong headlight control module. You need a module from a 1987-89 model year car. You have a module from a 1990-2002 model year which will not work for your car. Unfortunately the modules look the same and have the same part number molded on the case. That part number is for the case, not the module. Pop open the module with a flat-blade screwdriver and check the date code that is on the circuit board.

In another thread you posted that the motor runs for 5-6 seconds. That indicates the OEM hard gel bushings in the headlight actuator housing need to be replaced.

I sell several kits to repair the 2-wire motors. TDS 207280 has the 3 CNC machined Delrin bushings to repair one motor. TDS 209280 has 6 bushings and also includes gaskets, screws, nuts and synthetic grease. Both kits include detailed instructions on how to do the repair.

Lon