dashboard lighting

Inside the cab...appearance, repair, upgrades

Moderator: FORDification

Post Reply
68bumps
New Member
New Member
Posts: 51
Joined: Thu Mar 08, 2012 6:46 pm
Location: Midlothian IL

dashboard lighting

Post by 68bumps »

On my 68 f100, the dashlights don't turn on at all. At first I just thought that it was missing the bulbs, but when i replaced my speedometer i noticed that there were light bulbs and i tested both of them, they both work. I'm figuring it's just a problem with the wiring because the headlight switch works perfectly normal, but, only being 14, I figured it would be best to check on here.
User avatar
71PA_Highboy
Blue Oval Fanatic
Blue Oval Fanatic
Posts: 923
Joined: Tue May 23, 2006 11:32 am
Location: Denver of the East

Re: dashboard lighting

Post by 71PA_Highboy »

The headlight switch has a potentometer on the front of it... ceramic piece with coils of wire embedded in it, and a slider that contacts it.

Make sure those are good, and test the output to the Blue wire with red stripe (instrument lighting).

Did you turn the knob to make sure that they are as bright as they can be?

Also, there is a fuse to check... 4A IIRC.


Good luck!
Got Ford?
2 EarlyBroncos (68,69)
2 Classic Mustangs (69,70)
1 F250 4x4 (71) - OB - 360, NP435, D24, HPD60 4.10, D60,
1 94 Ranger, 2.3, 5spd
1 Lincoln Mark VIII
User avatar
1970 Hi-Boy
Preferred User
Preferred User
Posts: 344
Joined: Thu Mar 08, 2012 2:22 pm
Location: Middle Tenessee/Northern Wisconsin/wherever else I may roam to try and make a buck.

Re: dashboard lighting

Post by 1970 Hi-Boy »

Replacing your speedometer raised a flag to me, was the whole thing replaced along with the printed board on the back? These are not interchangeable from year to year, and your wiring harness wont match up. If so you can put just the speedometer head into your old gauge cluster. Just thought I'd check. I learned the hard way.
1970 F250 Sport Custom 4x4 360 V8, otherwise known as the Hi Boy, and a Harley-Davidson.

1953 Lincoln SA200 portable welder with a 4 cylinder 1941 Continental F162 engine.

"If you think you can do a thing or think you can't do a thing, you're right." Henry Ford
User avatar
TNIceWolf
Blue Oval Fanatic
Blue Oval Fanatic
Posts: 864
Joined: Sat Jan 03, 2009 9:52 am
Location: Tennessee Greeneville

Re: dashboard lighting

Post by TNIceWolf »

1970 Hi-Boy wrote:Replacing your speedometer raised a flag to me, was the whole thing replaced along with the printed board on the back? These are not interchangeable from year to year, and your wiring harness wont match up. If so you can put just the speedometer head into your old gauge cluster. Just thought I'd check. I learned the hard way.
That wouldnt be a problem on a 68 I would think. As far as I know all 67-69 used a instrument cluster that was all wired in. No printed circuit involved until 1970 if memory serves.
Find 'em....Buy 'em....Fix 'em.....Drive 'em....Love 'em

HHC 4/67AR.... Bandits.....88-92

Presently in the stable
1969 Ford F-350 DRW
1989 Chevy S-10 Tahoe ( It gets me to work and back and fetches parts and groceries)
1981 Buick Regal ( My deceased uncles last project/driver....renamed project Regal Eagle to be finished in his honor)
1990 Ford F-150 ( Miss Yvonnes Daily Driver )
My F-350 project http://www.fordification.com/forum/view ... 22&t=41744
User avatar
1970 Hi-Boy
Preferred User
Preferred User
Posts: 344
Joined: Thu Mar 08, 2012 2:22 pm
Location: Middle Tenessee/Northern Wisconsin/wherever else I may roam to try and make a buck.

Re: dashboard lighting

Post by 1970 Hi-Boy »

TNIceWolf wrote:
1970 Hi-Boy wrote:Replacing your speedometer raised a flag to me, was the whole thing replaced along with the printed board on the back? These are not interchangeable from year to year, and your wiring harness wont match up. If so you can put just the speedometer head into your old gauge cluster. Just thought I'd check. I learned the hard way.
That wouldnt be a problem on a 68 I would think. As far as I know all 67-69 used a instrument cluster that was all wired in. No printed circuit involved until 1970 if memory serves.
You are correct sir, sorry I blew up! It's the 70 vs the 71-72 that doesn't work, my bad. :oops:
1970 F250 Sport Custom 4x4 360 V8, otherwise known as the Hi Boy, and a Harley-Davidson.

1953 Lincoln SA200 portable welder with a 4 cylinder 1941 Continental F162 engine.

"If you think you can do a thing or think you can't do a thing, you're right." Henry Ford
User avatar
mybros71
Preferred User
Preferred User
Posts: 290
Joined: Tue Jan 27, 2009 11:00 pm

Re: dashboard lighting

Post by mybros71 »

Doesn't the cluster fuse also cover the tail light circuit?
2006 Mustang GT (Wife's)
1962 Comet Custom (Wife's)
1971 F100 2wd Prerunner Project (Daughter's)
1971 F250 4wd "The Beast" (Son's)
2007 Toyota Tundra 4wd. (Credit Union's)
Seriously, the best truck I've ever owned, without exception.
SmoothJ69
New Member
New Member
Posts: 100
Joined: Mon Mar 12, 2012 3:46 pm

Re: dashboard lighting

Post by SmoothJ69 »

71PA_Highboy wrote:The headlight switch has a potentometer on the front of it... ceramic piece with coils of wire embedded in it, and a slider that contacts it.

Make sure those are good, and test the output to the Blue wire with red stripe (instrument lighting).

Did you turn the knob to make sure that they are as bright as they can be?

Also, there is a fuse to check... 4A IIRC.


Good luck!

I replaced my headlight switch just recently to fix this very problem, dash lights not working. The spring on the old one was corroded and broken.
User avatar
mybros71
Preferred User
Preferred User
Posts: 290
Joined: Tue Jan 27, 2009 11:00 pm

Re: dashboard lighting

Post by mybros71 »

There you go.
2006 Mustang GT (Wife's)
1962 Comet Custom (Wife's)
1971 F100 2wd Prerunner Project (Daughter's)
1971 F250 4wd "The Beast" (Son's)
2007 Toyota Tundra 4wd. (Credit Union's)
Seriously, the best truck I've ever owned, without exception.
Post Reply