Tail lights

[Jalps]

My tail lights do not light with headlight switch, but work with fog light switch and brakes. any help as to where I should look to fix this problem.

[retired mechanic74]

Mine behaves the same way I have come to believe it is in the headlight switch. Mine is intermittent sometimes it does but more then often it don't. Have not been able to find a switch so I just got use to using the fog switch. The one thing good about it is the fog switch is controlled by the ign.

[DAVES89]

The 1990 Reatta headlight switch is a one year Reatta only switch. I sold two of them when I was at Brookfield for the Buick National Meet. One was NOS and the other was lightly used and in original condition.

I have two other rebuilt ones with another one or two coming, but am reluctant to part with them.

I do have one that works great except for one thing. When I choose to go to brights the back lighting on the radio and temperature control goes out. When I switch back to dims the back lighting comes back on. 

 I keep it in my glove box as an emergency spare. This switch I would part with if anyone wants to buy it.

[retired mechanic74]

One thing I'm going to try, I'm going to take the headlight switch apart and clean the contacts. I had an issue with the wiper switch where if you put the switch on hi the wipers would raise up 3 inches and slap back down and it would keep repeating this until I shut them off. All I could use was the pulse wipers. I took the switch apart and found dirty contacts. Once I sanded the contacts I've not had that problem sense. I think that could also be the problem with the headlights...........I'll let you guys know.

[DAVES89]

Big difference between the 1988/89 switches and the 1990/91 switch [1991 switch is interchangeable with the Riviera]. I have taken the 88/89 switch and had good results, but the 1990/91 switch is way different and much harder to rebuild.

[DAVES89]

Jim Finn offers a recondition service or you could check ebay.

[2seater]

I can vouch for Dave or Jim. Both offer good parts at good prices. I burned up two '90 switches with high power headlights until I did the aux. power modification which I highly recommend, especially for '90 owners.

[retired mechanic74]

I can vouch for Dave or Jim. Both offer good parts at good prices. I burned up two '90 switches with high power headlights until I did the aux. power modification which I highly recommend, especially for '90 owners.

 

    2 seater you mention an aux. power modification?? Is this the adding of a relay which the ground there of would be controlled by the headlight switch with a fused constant hot wire to the lights therefore eliminating voltage spiking on the switch?

[2seater]

 

    2 seater you mention an aux. power modification?? Is this the adding of a relay which the ground there of would be controlled by the headlight switch with a fused constant hot wire to the lights therefore eliminating voltage spiking on the switch?

 

There was a thread a few years ago on the AACA forum about why headlights wouldn't close. In the process of the very lengthy thread, we discussed the need, particularly on the '90, to take the load off the headlight switch. As a matter of fact, the factory made a running change to add a relay in the console to do just that, but the wimpy factory wiring was still the same. I have 80/100w headlights and had burned up the headlight switch so we developed a relay system under the hood and modified wiring. The pop-up headlights complicate things as the headlight module must see a ground when the headlights are off for them to close. It all worked out after a while and the headlights are noticeably brighter.  In the similar time frame, Daves89 tried LED headlights, where power isn't the problem but lack of reverse ground is. He found a relatively simple aftermarket harness that solves both problems.

[DAVES89]

That harness is for sale in Ronnie's store...

[retired mechanic74]

I took the headlight switch apart and cleaned all 8 contacts, now the system is working fine.

[retired mechanic74]

 

There was a thread a few years ago on the AACA forum about why headlights wouldn't close. In the process of the very lengthy thread, we discussed the need, particularly on the '90, to take the load off the headlight switch. As a matter of fact, the factory made a running change to add a relay in the console to do just that, but the wimpy factory wiring was still the same. I have 80/100w headlights and had burned up the headlight switch so we developed a relay system under the hood and modified wiring. The pop-up headlights complicate things as the headlight module must see a ground when the headlights are off for them to close. It all worked out after a while and the headlights are noticeably brighter.  In the similar time frame, Daves89 tried LED headlights, where power isn't the problem but lack of reverse ground is. He found a relatively simple aftermarket harness that solves both problems.

 

Thanks for the heads up, I'm not experiencing any problems with that yet, but I did find the wiring for the motors were rubbing against the hood and wearing away the insulation I found it necessary to take the ball part of a ballpene hammer and dent in the hood at that point. The only other way would have been to adjust the hood stops but that caused a mis-alignment.

[Ronnie]

I took the headlight switch apart and cleaned all 8 contacts, now the system is working fine.

 

Way to go!

[Ronnie]

'm not experiencing any problems with that yet, but I did find the wiring for the motors were rubbing against the hood and wearing away the insulation I

 

There is a guide on this website that shows how the headlight wires should be routed. If they were routed wrong (by someone else) the wires are prone to breaking at or near the headlight plugs. You might want to check that.

[retired mechanic74]

 

There is a guide on this website that shows how the headlight wires should be routed. If they were routed wrong (by someone else) the wires are prone to breaking at or near the headlight plugs. You might want to check that.

 

Do you know if the motors are left and right? If they are then they were installed wrong and I would switch them If not then my fix is working well. Sense I don't plan on selling this car the modifications I'm making to it are fine.

[DAVES89]

The motors are left and right.

[retired mechanic74]

The motors are left and right.

 

    Thanks