3G Alternator Upgrade-Now I have Head Light issues!

[MikeR351w]

Ok, I have a 93 Mustang 5.0. I just put in the 130amp kit and fired up the car. Everything appeared to be ok, until I tried my headlights. EVERYTHING else works, except for the headlights. And heres the kicker, the high beams work! So last night I had to drive around with my high beams on because I could not use the regular head lamps. What is going on!

 

[HISSIN50]

If you use flash-to-pass, do the low beams come on with the highs? This tells ya if the bulbs and wiring from the MF and forward is good. I'd be lookin at the MF initially however.

Fuses good?
Good luck.

 

[jrichker]

Another vote for multifunction switch problems. Scary coincidence, you fix one problem and another surfaces at the same time... must have something to do with Halloween...

A word of caution about multifunction switches is in order here. The multifunction switch (high/low beam, wiper, turn signals) are different for different years. 87-98 will work in any 87-89 car. The 90-93 switches only work in 90-93 cars. You can't put an early model switch in a late model car, nor can you put a late model switch in an early car.

Supposedly you can move the pins around to make the switches work in model years that are different from the car the switch came out of. I cannot verify that and haven’t tried it .

 

[MikeR351w]

Before the alternator swap, my headlight switch worked properly. After the swap, it did not work. All my lights, radio, turn signals, running lamps work except for the normal head lamps. Also, I was using an 87 head lamp switch on my dash and my car is a 93. It was fine for 3 years like that. The only reason I dont think that it is the switch is because it was working fine before the swap and after it did not work. Thanks for the insight so far! I will try another switch and see if that works. In the mean time, is there anything else I should check?

 

[HISSIN50]

I suppose knowing if the lows worked during Flash-to-pass would have helped [me, at least].

Your messing around the solenoid should not have affected things since the rest of the running lights work.

You dont have a stand-alone relay for the low beams, right? A logical place to source power for it would be the solenoid, and if that wire was left off the solenoid............

I think it will require some more info from you for folks to help.

Good luck.

P.S., Joe, speakin of coincidences, that's just how I lost my headlights [years ago]. I was doing another (unrelated) install and afterwards, had no highs or lows. FTP was good though. Turns out that I must have bumped an underdash-harness a little bit and it allowed the headlight-feed into the MF switch to get pulled-out a little bit.

 

[MikeR351w]

The flash to pass works and I dont know how to tell if the high and low beams are working at the same time. I was thinking that some wiring got messed up somewhere but I did not touch any wiring other than the alternator harness. Do you think the problem is the head lamp switch on the dash>? I have another from an 88GT w/fog lamp switch. Would that work????

 

[HISSIN50]

The flash to pass works and I dont know how to tell if the high and low beams are working at the same time. I was thinking that some wiring got messed up somewhere but I did not touch any wiring other than the alternator harness. Do you think the problem is the head lamp switch on the dash>? I have another from an 88GT w/fog lamp switch. Would that work????

You noted that your high beams work. That means the 'headlight' feed from the headlight switch is making it to the MF switch. It's the MF switch that toggles between lows and highs. So it sounds like your headlight switch should be alright.

If you turn on your high beams (like you have been while driving at night) and then hit flash-to-pass, do the lights get brighter? If so, that would indicate that the lows are coming on. If that happens, I'd look real hard at the MF switch.

If the lights dont get brighter during the FTP-while-brights-are-on test listed above, you need to ascertain if the low-beam circuit/components were damaged. That's why that info would have been helpful.

Good luck.

 

[Saleen0679]

If you turn on your high beams (like you have been while driving at night) and then hit flash-to-pass, do the lights get brighter? If so, that would indicate that the lows are coming on. If that happens, I'd look real hard at the MF switch.

If the lights dont get brighter during the FTP-while-brights-are-on test listed above, you need to ascertain if the low-beam circuit/components were damaged. That's why that info would have been helpful.

Good luck.

Isn't that going to be difficult since pushing the lever forward (away) from the center (low beam) detent activates the high beams while pulling backwards activates flash-to-pass? You wouldn't be able to get both. FTP would activate high beams anyway so you wouldn't notice a difference in brightness.

I think the easiest and quickest way would be to take a meter to the MF switch and check I/O voltages for the low beam circuit.

 

[HISSIN50]

Isn't that going to be difficult since pushing the lever forward (away) from the center (low beam) detent activates the high beams while pulling backwards activates flash-to-pass? You wouldn't be able to get both. FTP would activate high beams anyway so you wouldn't notice a difference in brightness.

I think the easiest and quickest way would be to take a meter to the MF switch and check I/O voltages for the low beam circuit.

Oh highly-respected-one , my car might be weird but my experience is a little different. When I was considering wiring my brights so that they would illuminate lows and highs simultaneously (don't worry, I didn't do it), one reason was because I could see all the lower-roadway filling that the lows provided [while brights were on]. It was quite noticable to me but we all know I'm an oddball.

I agree that checking voltage at the MF switch would be easiest, but not everyone finds doing such things as second-nature as you and Joe do. I thought the comparison test would be super quick and dirty but I guess I was wrong.

 

[Saleen0679]

I agree that checking voltage at the MF switch would be easiest, but not everyone finds doing such things as second-nature as you and Joe do. I thought the comparison test would be super quick and dirty but I guess I was wrong.

That other statement was more directed at the OP. I figured it would eliminate all the guessing and head scratching.

 

[HISSIN50]

That other statement was more directed at the OP. I figured it would eliminate all the guessing and head scratching.

Just like that which always comes from Joe, yours is always almost robotically (a compliment) sage advice.

 

[MikeR351w]

Ok, I tried the HD lamp switch from the 88 GT and it still does not work. Again, I have all running lamps, turn signals, and every electronic item except for regular low beam head lamps. What else should I check?

 

[MikeR351w]

Fixed!!!!!!!!!! :SNSign:

The problem was not as complex as we thought. It turns out that the wire that goes into the wiper arm/turn signal/high beam switch was loose. Specifically, the large red wire that goes into the gray high beam electrical connector. All I did was push it back into the connector and used some electrical tape to keep it in place. Thanks for all your help!!!!!!!!!!!!