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Topic: What's with me and headlight switches? (Read 2531 times) previous topic - next topic

What's with me and headlight switches?

Reply #15 –
Another observation:

The dome light and chime (for keys and or lights) only work if autolamp AND the headlight switch is in park or head...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

What's with me and headlight switches?

Reply #16 –
I am trying to figure out the headlight circuit on my 01 Grand Marquis. The headlight switch outputs go to the lighting control module.
I suspect the headlight current load does not go through the switch.

Maybe the Mustang has the same set-up and the switch can't handle the current load required in our cars. Also the switch does not have the built-in circuit breaker.

I'm going cross eyed trying to figure it out.

What car did you get your autolamp feature from?

What's with me and headlight switches?

Reply #17 –
LOL  well, the problem existed BEFORE the mustang switch so I'm not concerned about that issue.  It also appeard to be setup like the thunderbird switch (no module, just a relay).

The autolamp was from an Thunderbird Elan (whatever year they made those) but it should be the same as the thunderbird autolamp for my 88 (snapped right in).

If I can't figure it out I may need to remove the autolamp and see what problems I still have.  Only problem is I don't have the dummy plug that went in place of the 8 pin connector...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

What's with me and headlight switches?

Reply #18 –
What wrong with your Grand Marquis?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

What's with me and headlight switches?

Reply #19 –
Nothing wrong with the GM. Just thought maybe your switch came from a newer Mustang that had the same set-up.

Older cars autolamp is different. From my 84 EVTM it has one relay that controls both the headlights and parks. Don't know what year they changed to two relays.

What's with me and headlight switches?

Reply #20 –
I gotcha.  As for the autolamp, it has 3 relays connected to the add-in harness (just like you see in that evtm picture).
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

What's with me and headlight switches?

Reply #21 –
Ok, I also just remembered I had one wire that didn't go anywhere on the mustang switch.  I looked it up and it turned out to be the chime/warning ciruit.  So, I need to connect this to get power when the lights are on.  I don't know if this will change anything with my problem but I want to find out.  My question is, since there is no output just for the chime on the mustang switch, should I connect it to the parking lamp output or the dash illumination output?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats
 

What's with me and headlight switches?

Reply #22 –
Update:

I finally got around to replacing all 3 relays on the autolamp harness.  Same problems:  Manual light switch works fine but autolamp only turns on the headlights and fog lamps.  I have to pull the light switch out to the 'park' position to get the extra parking, marking and tail lamps to come on.  Potentiometers are also recently replaced as was the light sensor.  All JY parts so they could be bad.  Anyone have an idea where to start after the relays?  (also, I should probably go home and swap relay 1 and two to make sure I didn't replace one with a bad JY relay)...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats