Headlight issue

[KirkV]

So driving 0678 home last night near dark and the headlight went dark. Had the brights on but when I hit the bright switch to turn them off I still had nothing.

I was only a mile from the house so no big deal, but today I dug into it. I have no power to the headlight on dim or bright so it is not a ground issue. I check the fuse and find it’s good, and start trying to manipulate the switch out of the dash to check it but can’t seem to get enough wire to get it out of the bottom to test.
I check again and I have brights as long as I hold the bright switch down but no dims yet.
I found the fan relay, the bright relay, but not the dim relay. I am about ready to wait till winter and pull the dash to get access to all of the wiring and get the two relays re mounted I took out I could reach.

Any other suggestions would be appreciated as I can tie wrap the bright switch if needed till then but I hate having something rigged to work.

I stil have running lights and brake a turn signals just no dim headlights?
Thx kirk

[Tom Wells]

Kirk,

Here are a couple of seemingly related threads: Headlight relay replacement... and Low Beams Not Working (first night drive)

I'll bet someone here could tell you exactly where that relay is located!

Hope this helps,

Tom

[Blas]

The relay in question is located on the back side of the dash. There are a grouping of 3 relays there. That are laced to the dash. If original, the relay in question is silver in color. But due to the age of your car, I would bet it has been replace at least once and I’d probably loose and easily accessible.
Reference part numbers are on my Wiring Diagrams.
Blas

[KirkV]

Blast is it accessible any way but dropping the dash? I found the fan and brights relay but not the sims relay. Or is the brights relay the dim light relay as well?

[Blas]

I am still in Bolder for the Shelby show last Saturday. I return home tomorrow. I can send you a photo then. There are 3 relays that are mounted close together with 3 separate plastic zip ties. I use a long pair of surgical hemostats to crack the zip ties. All three relays will drop down and then be accessable. All headlights (std and brights) run thre one relay. It is called a latching relay. (DIN 0127 if I recall)
There is the start inhibit relay there and the fan relay too.
Blas

Who’s BLAST.

[ACHiPo]

Could be the relay, but could also be the connection under the front fenders. I had a similar issue. After replacing the relay it still didn't work. Pulling the connectors apart and cleaning contacts with Caigs contact cleaner the low beams worked again.

[KirkV]

Who’s Blast? Damn autocorrect lol, ok so I have the correct relay pulled down as it clicks in when I pull the bright switch but does not latch in.
Thanks so much and I will get another switch ordered.

[Blas]

The latching relay will click when a ground is MOMMENTARILY sent to it via the switch on the stalk. If you manually hold a ground wire to it for and extended period you fry it.
Blas

[ACHiPo]

Another thing I had to do was pull the dimmer switch off the stalk and emery the contacts--that momentary thing that Blas talks about.

[Gaz64]

Originally Posted by Blas

The latching relay will click when a ground is MOMMENTARILY sent to it via the switch on the stalk. If you manually hold a ground wire to it for and extended period you fry it.
Blas

And why does that occur?

Sounds like a design fault.

Any relay I know of can be setup as a latch, and the operate momentary pulse width (even on permanent) makes no difference.

[KirkV]

Blas,

I got my new relay and all is good the lights work like a dream. Thanks so much
Kirk

[Blas]

Excellent.......

[bobbybeige]

Where under the dash is this relay? Bent my old body under there to try and find it, then I needed a crane to pull myself out. Can't find it.

[Blas]

Send me a message and include your car number. Can be in multiple positions depending on chassis number....Blas