Register or Log In To remove these advertisements. |
|
|
|
Thread Tools | Display Modes |
09-27-2015, 08:51 AM | #1 |
Registered User
Join Date: Sep 2014
Location: Florida
Posts: 184
|
Headlight Switch Trouble
I have been scratching my head trying to figure this one out for a while, even though I'm not the brightest crayon in the box when it comes to electrical stuff. The headlight switch in my truck doesn't work correctly, the only lights I can control with the knob are the headlights. Marker lights, dome light, even brake lights don't work when the switch is plugged in!
Somehow I figured that I could hard wire the connection in the plug to test the wiring. I removed the switch and found the hot "POWER" wire in the plug, then ran a short lead to each terminal to test the lights. Run a wire from "HEADLIGHT" to "POWER" and the headlights turn on, "MARKER LIGHTS" to "POWER" and the marker lights turn on... When I have these three terminals wired to the "POWER", the lights are on and everything is great... but when I put the switch back on, only the headlights work. If I have the switch on, I found that I could run a lead as shown in the pic below, then the switch would work perfectly... I can dim the cluster lights, I can turn on the dome light, the brake lights work too, but only if I run a wire as shown by the blue line. What is happening here? there is obviously power reaching the switch... but I have tried three different switches and none of them work without the modification I have mentioned above. Any help would be appreciated. |
09-27-2015, 09:01 AM | #2 |
Registered User
Join Date: Apr 2009
Location: houston texas
Posts: 1,438
|
Re: Headlight Switch Trouble
im no electrician. does dimmer switch work properly? most electrical problems are bad ground.
|
09-27-2015, 09:25 AM | #3 |
Registered User
Join Date: Sep 2014
Location: Florida
Posts: 184
|
Re: Headlight Switch Trouble
The dimmer work fine if I hard wire the plug as shown in the second pic. If the dimmer switch is plugged in without the (blue in my picture) wire, it will only turn the headlights on and off.
|
09-27-2015, 09:28 AM | #4 |
Registered User
Join Date: Oct 2013
Location: Dresden, Ontario
Posts: 647
|
Re: Headlight Switch Trouble
Sounds like your headlight switch is bad.
__________________
1970 Short Wide 5.3 4L60E BlackBear tune 3:73 gears, Boyd's Tank 2.5 / 4 drop 5 lug disc brakes Vintage Air 18x8 Ridlers 255/55 frt. 18x9.5 275/60 rear |
09-27-2015, 09:52 AM | #5 |
Registered User
Join Date: Sep 2014
Location: Florida
Posts: 184
|
Re: Headlight Switch Trouble
Is there a good quality switch I should try? I've bought one switch from ClassicParts.com and another from NAPA, plus the one that was in the truck when I bought it, so far all three switches have had the same issue.
|
09-27-2015, 11:15 AM | #6 |
The Older Generation
Join Date: Aug 2006
Location: Montezuma, Iowa
Posts: 25,575
|
Re: Headlight Switch Trouble
-
I can't believe it's the switch if you have tried 3 of them but I guess it could be possible. Here is a labeled picture of the switch posted by VetteVet. He labeled the "Brown" as '68 up. What year is your truck? LockDoc
__________________
Leon Locksmith, Specializing In Antique Trucks, Automobiles, & Motorcycles (My Dually Pickup Project Thread) http://67-72chevytrucks.com/vboard/s...d.php?t=829820 - Last edited by LockDoc; 09-27-2015 at 11:22 AM. |
09-27-2015, 12:24 PM | #7 | |
Registered User
Join Date: Sep 2014
Location: Florida
Posts: 184
|
Re: Headlight Switch Trouble
Quote:
Looks like if I connect the "Done/courtesy" terminal directly to the "12v in", then the switch works correctly. But without the extra wire connecting the two, the switch only functions to turn the headlights on and off. |
|
09-27-2015, 07:17 PM | #8 |
Msgt USAF Ret
Join Date: Jan 2005
Location: Kalamazoo, Michigan
Posts: 8,715
|
Re: Headlight Switch Trouble
What you are missing is the orange wire power to the headlight switch. It appears that you have an orange wire to the switch plug which originates at the fuse panel.
notice the orange wire in the diagram that starts at the fuse panel in this pic. This one shows the orange wire to the headlight switch. This is a full time hot wire so check it for power at the headlight plug, and at the tail stop fuse. I can't seem to find it right now but I'll post it later if I find it.
__________________
VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative. |
09-27-2015, 07:55 PM | #9 |
The Older Generation
Join Date: Aug 2006
Location: Montezuma, Iowa
Posts: 25,575
|
Re: Headlight Switch Trouble
-
The "Orange" (Dome-Courtesy) terminal actually feeds the terminal labeled "Brown" through the switch when it is on. It is not fed from the "Bat" or "Power" terminal. LockDoc
__________________
Leon Locksmith, Specializing In Antique Trucks, Automobiles, & Motorcycles (My Dually Pickup Project Thread) http://67-72chevytrucks.com/vboard/s...d.php?t=829820 - |
09-27-2015, 10:31 PM | #10 |
Senior Member
Join Date: May 2012
Location: Scottsdale, AZ
Posts: 1,906
|
Re: Headlight Switch Trouble
I was told by AAW that there is only one company that manufactures the replacement switches. I have a low opinion of them, as I am on my third one. I am using my original switch, I cleaned it up and got the dimmer working which was the only problem with it to begin with.
__________________
White K20 |
09-27-2015, 11:11 PM | #11 |
Msgt USAF Ret
Join Date: Jan 2005
Location: Kalamazoo, Michigan
Posts: 8,715
|
Re: Headlight Switch Trouble
......
Here's the diagram to the headlight switch. In the first one it shows the orange wire in the middle of the fuse panel and how it's fed from the battery alternator junction. It branches off to feed the stop light switch , the dome light and the headlight switch brown wire for the markers and parking lights. If you don't have power there then those things won't work.
__________________
VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative. |
09-28-2015, 09:16 AM | #12 | |
Registered User
Join Date: Sep 2014
Location: Florida
Posts: 184
|
Re: Headlight Switch Trouble
Quote:
So I need to check that the orange wire is getting power at the fuse box? I remember seeing the orange connection when cleaning the back of the fuse box, but it didn't have a clip-on connection like the other wires, it was either soldered or crimped directly to the back of the fuse panel. Because of that I wasn't able to clean the contact surface, and didn't pay much attention to that connection. If I understand correctly, the orange wire should have power all the time... it currently does not get any power unless I manually connect it to a 12v source with a spare piece of wire. Looking at the diagram, it looks like the orange wire gets its power through a circuit connected to the red wire on the back of the fuse box (black line connect red and orange wires)? Could it be that the circuit between the red and orange wires is broken (behind the fuse panel), and that's why everything works when I complete the circuit with the added wire at the headlight switch plug? Sorry if I got it all wrong, I don't have much experience reading wiring diagrams |
|
09-28-2015, 09:22 AM | #13 | |
Registered User
Join Date: Sep 2014
Location: Florida
Posts: 184
|
Re: Headlight Switch Trouble
Quote:
|
|
09-28-2015, 02:39 PM | #14 |
Senior Member
Join Date: May 2012
Location: Scottsdale, AZ
Posts: 1,906
|
Re: Headlight Switch Trouble
This is a salient point, each "bad" switch I had suffered from a different affliction. So, if something works with one switch and not another that's a test. If same thing does not work on all switches it's inconclusive. Just hoping you can eliminate the switch as the culprit in your process of elimination. If you follow what Vet laid out you will be able to trace your issue.
__________________
White K20 |
09-28-2015, 04:01 PM | #15 |
Registered User
Join Date: May 2014
Location: PA
Posts: 1,417
|
Re: Headlight Switch Trouble
If all 3 switches have done the exact same thing I wouldn't pay any more attention to the switch. There is likely something wron in your turn signal switch (a lot of things run through it) or your fuse panel/wiring harness.
__________________
1967 C10, LWB, 250, Powerglide, PS, PB, 3/4 STATIC DROP |
Bookmarks |
Thread Tools | |
Display Modes | |
|
|