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tbirdwillie
11-22-2002, 11:55 PM
Help please. I have no headlights on my 93 SC. The parking & tail lights come on when switch is activated but no headlights. Changed headlight switch and checked fuses. No luck. Test light indicated no power to headlight socket, except when you pull up on directional arm to activate high beams. Thats the only time there's power to the high beam headlights. Sure could use some advise. Thanks

Thrty5thSC
11-23-2002, 01:12 AM
your high beem switch could be bad.

tbirdsc35th
11-23-2002, 02:25 AM
Just trying to follow you here. I always want to be ahead of problems in the future. Am I correct that you have no high beams except when you pull back on the wiper/bright switch for the flash to pass mode? Do you have brights when you push the wiper switch forward toward the dash to the bright postion? If the 93's are like the 90's, your power for the dims are through the multifunction switch. With power only to the brights in flash to pass, it sounds like the MFS is what might have gone out. Just trying to help.

joshbea6
11-23-2002, 03:37 AM
First off, do you have the auto dimming headlights? and where are you testing the high beams? Get back to me on this. IF you have the auto dimming headlights then you could have the same problem that I had.

corder13
11-24-2002, 04:14 PM
Just to let you know, there IS a recall for the headlight switch, and fog light switch/wiring on the MN12 T-Birds. I believe from '91-'93. Maybe '90-'93, though, but your car is covered in that recall. I had to get mine done, too. Try turning off the fog lights to see if that does anything at all. If not, it may have already burnt something up. :(

Rick

tbirdwillie
11-26-2002, 06:50 PM
Originally posted by tbirdsc35th
Just trying to follow you here. I always want to be ahead of problems in the future. Am I correct that you have no high beams except when you pull back on the wiper/bright switch for the flash to pass mode? Do you have brights when you push the wiper switch forward toward the dash to the bright postion? If the 93's are like the 90's, your power for the dims are through the multifunction switch. With power only to the brights in flash to pass, it sounds like the MFS is what might have gone out. Just trying to help. :confused:

tbirdsc35th: I do not have brights when you push the wiper switch foward to activate the bright lights. I am not getting power to the headlights, low or high via the headlight switch or auto switch. I've tried it with the auto switch in the off position and without the fog lights on. No luck. Where is the MFS at?

tbirdwillie
11-26-2002, 06:54 PM
Originally posted by joshbea6
First off, do you have the auto dimming headlights? and where are you testing the high beams? Get back to me on this. IF you have the auto dimming headlights then you could have the same problem that I had.

:confused: Yes, I do have auto dimming headlights. I was testing both low and high beam lights. No luck. Thanks!

tbirdsc35th
11-26-2002, 08:42 PM
Hi, tbirdwillie.

I'm looking at the EVTM. The automatic headlamps adds a number of differences in the system. In the troubleshooting section, No high beam and no low beam could be from an "inoperative Headlamp Dimmer Sensor" and no low beam also suggests the Hi-Lo Beam Relay. I can see that a faulty Hi-Lo relay could stop current to low beams. If you have neither hi or low beams but do have flash to pass, it sounds like it may be your Headlamp dimmer sensor. Check to see if you have flash to pass. A bad relay only seems to affect the low beams. Your multifunction switch, or MFS, is simply the switch on your steering column that is the wipers, headlights, bright light mode, and such. If you have no flash to pass either, then the EVTM suggests that your MFS is bad. There is a sequence of procedures to test the sensor and relay. If you need me to pass it along, I can type it out for you. I would definitely check with joshbea6 also. If he's been there, he may be able to help you better.

Good Luck.

tbirdwillie
11-26-2002, 09:50 PM
Originally posted by tbirdsc35th
Hi, tbirdwillie.

I'm looking at the EVTM. The automatic headlamps adds a number of differences in the system. In the troubleshooting section, No high beam and no low beam could be from an "inoperative Headlamp Dimmer Sensor" and no low beam also suggests the Hi-Lo Beam Relay. I can see that a faulty Hi-Lo relay could stop current to low beams. If you have neither hi or low beams but do have flash to pass, it sounds like it may be your Headlamp dimmer sensor. Check to see if you have flash to pass. A bad relay only seems to affect the low beams. Your multifunction switch, or MFS, is simply the switch on your steering column that is the wipers, headlights, bright light mode, and such. If you have no flash to pass either, then the EVTM suggests that your MFS is bad. There is a sequence of procedures to test the sensor and relay. If you need me to pass it along, I can type it out for you. I would definitely check with joshbea6 also. If he's been there, he may be able to help you better.

Good Luck.

tbirdsc35th: Hey, I really appreciate your help. If it wouldn't be too much trouble could you please e-mail me the procedures to test the sensor and relay. My e-mail address is: Carbone2@comcast.net. Thanks again!!

tbirdsc35th
11-26-2002, 10:56 PM
Sure. I'll just put it here for others if they need it too.

No High Beam -
- Check Headlamp Dimmer Sensor vertical level adjustment
- Remove connector from Headlamp Dimmer Sensor and pull the lamp switch all the way out. Ground the 505 (Gray/Yellow stripe) wire on the Hi-Lo Beam Relay wiring harness connector.
- If headlamps switch to hi beam when the Autolamp/Auto Dimmer Control is moved to AUTO-HI position, replace the Headlamp Dimmer Sensor.
- If headlamps don't switch to hi beam, test the Hi-Lo Beam relay and Multi-function switch.

No Lo Beam -
- Check that photocell is clean and senses through window.
- Remove connector from Headlamp Dimmer Sensor, set the headlamp control to MAX RANGE, and pull the headlamp switch all the way out.
- Check range control resistor by measuring voltage between circuit 508 (white wire) and ground. With the Autolamp/Auto Dimmer Control resistor at MAX range, voltage should be slightly less than battery voltage when the Hi-Lo Beam Switch is moved to the AUTO-HI position. Rotate the resistor slowly to the MIN position. The voltage should drop smoothly lower to 3 volts and then go to zero at the MIN position.
- Remove Hi-Lo Beam Relay and check for continuity between pin number 3, circuit 15 (Red/Yellow stripe wire) and pin number 5, circuit 13 (Red/Black stripe wire).
- if above tests prove OK, and the headlamps returned to low beam when the Headlight Dimmer Sensor was disconnected, replace the Headlamp Dimmer Sensor. If headlamps did not return to low beam, check for a grounded circuit 505 (Gray/Yellow stripe wire).

No Flash to Pass -
- Check Multi-function switch for continuity between the 196 (dark blue/orange stripe wire) and 527 (Red wire) terminals with the Multi-function switch in the Flash-to-pass position.

- Check Cigar LTR Fuse.

Hope this helps.

TBirdDriver
11-27-2002, 05:06 PM
Identical circumstances happened to me,and I mean identical, except it wasn't on my T-Bird, it happened to my Ford Explorer.
It drove me nuts. Turned out to be that the wire harness that connects to the back of the multi-function switch was not seated correctly. (The plug itself was not holding the wires properly, so I used needle nose pliers to push each wire connection into place.)
Just something to check.

(Also, I assume you replaced the bulbs, because they can both go at the same time, (it's happened to me)).