Ford TSB 89-17-11 says this is caused by overheating in the headlamp circuit. It's a phenomenon affecting '83-'89 Escorts, '83-'87 EXPs and '87-'88 Mustangs. You'll need to replace the headlamp and dimmer switches, several connectors, and then bypass the wiring in the circuit with new 12ga wire run alongside the original harness.
Get yourself one of these harnesses to keep your headlight switch from burning up:
http://www.rjminjectiontech.com/products/headlight-harness
Then do this relay modification for your fog lights:
http://www.corral.net/tech/maintenance/foglights.html
Then read this:
http://www.candlepowerinc.com/pdfs/9004_9007.pdf
http://www.rjminjectiontech.com/products/headlight-harness
Then do this relay modification for your fog lights:
http://www.corral.net/tech/maintenance/foglights.html
Then read this:
http://www.candlepowerinc.com/pdfs/9004_9007.pdf
http://www.danielsternlighting.com/tech/relays/relays.html
This is another good link for researching headlight upgrades. The whole site is worth a look IMO.
This is another good link for researching headlight upgrades. The whole site is worth a look IMO.
The low beam of a 9007 draws 0.83 more amps than the 9004 (assumed at 12V). The last link I provided outlines the reasons not to swap a 9004 bulb for a 9007, but if you must, all you'll need to do it switch some pins around on the car side of the headlight wiring and plug the RJM 9007 harness into it.
The reflector in fox body Mustangs is designed to use the 9004 bulbs. The mathematics that govern the distance between the filament and the reflector are precisely calculated for maximum efficiency. Those of you who have studied Calculus in college will understand that the reflector is a parabola with the filament as the central point.
The 9007 use a different filament arrangement that does not match the fox body parabolic reflector, and for this reason, it will produce less effective light, or light that does not align its output to the proper pattern. The modified headlight may direct its light into the eyes of the oncoming driver, off the side of the road or up in the trees above.
The 9007 use a different filament arrangement that does not match the fox body parabolic reflector, and for this reason, it will produce less effective light, or light that does not align its output to the proper pattern. The modified headlight may direct its light into the eyes of the oncoming driver, off the side of the road or up in the trees above.
You will get a noticable difference in light output if you install a 9004 harness like the one from RJM. Your headlights will then be sourcing their power directly from the battery, so they will see the full 14V coming off the alternator. Voltage drop won't be an issue anymore.
You probably don't want to attempt an HID retrofit. It's not a good time.
You probably don't want to attempt an HID retrofit. It's not a good time.
I used Daniel Stern's website as my guide when buying bulbs. Ordered some GE Nighthawks from Amazon. Love them, will absolutely buy them again. They make a huge difference even without retrofitting relays.
One part of the harness plugs into the driver side 9004 male plug from the stock wiring. The other part gets a ground and 12V from the battery. It just turns the stock plug into a signal wire to tell the relays when to turn on the headlights which now draw their power directly from the battery.
So it will kill my battery if i leave these 9007 bulbs on ? The funny thing is the person who owned this car before me had the 9007's in there. When one blew out, i replaced it with a 9004, and it killed my battery. So now i purchased both the 9007's. I will have to wait to see if it starts withing the next few days. Although, he upgraded the stock headlights to a one piece headlight piece. I hope he did the conversion right, or i will find out the hard way.
Some the links either don't work anymore or the information on them has changed.
RJMInjectiontech.com was one of companies that had a threating letter from Ford about using the Ford name in their old site fordffuelinjection.com.
Its actually just switching one wire with one other, seems pretty simple from what i saw on the diagram. I hope to have no issues, but will update if i do. So far, i think i found what was causing my battery to die, and it wasn't the headlights. It was the dam mirror on the sunvisor. I saw it on when i entered my garage at night. Gave it a good slap, and it turned off.