Brake lights stuck on, no headlights???

[A66Auto]

I need some electrical help and I will try to be as clear as possible. The under dash wiring in my 66 coupe has been hacked to s*** over the years. I mean there were so many splices and things going on that I had to zip tie the harness up under the dash so it would not fall and get tangled in my feet while I was driving. Now that I can afford it, I decided to buy a new factory under dash harness from NPD and rewire it my self and it really was not that hard with a diagram and a few spare hours. Everything works except:

My brake lights and licenses plate lights are stuck on and my head lights will not turn on when the knob on my head light switch is “clicked” all the way to the left. If I “unclick” my lights to the right, the brake lights turn off , but the headlights still will not turn on and stepping on the break pedal will not turn the lights back on.

I have double checked everything I could and do not know how to trouble shoot this problem. The headlight switch is about 2 years old and the high/low beam selector is about the same age. I have not connected the dash lights yet because I broke some bulbs and have to wait until tomorrow to get new ones. My front and back turn signals work just fine.

Any help is appreciated thank you.

Alex

 

[1966conv]

I'm a little confused here. An oem style headlight switch is the pull on/push off type; not click on left or right; those if I'm reading this properly are for the courtesy "underdash" lights.
Have you replaced the turn signal switch? It sounds like the connector on the turns signal switch has been wired incorrectly.

 

[A66Auto]

I am sorry. Yes, when you turn on the courtesy lights the brake lights come on. pulling the headlight swith will not turn on the head lights. I did not replace the turn signal switch at all. I will check that switch and give an update

 

[1966conv]

Lets think about this semi-logically for a minute. You replaced the underdash harness; did you replace the headlight harness? "Assuming" (maybe wrongly) that the headlight harness works properly, it plugs in at the firewall (check connection) and plugs in at the headlights and at the solenoid on the engine side of the firewall. Not much can really go wrong there.

The underdash harness has the funny looking plug at the headlight switch.(check connection) Other than a broken wire, poor or bad connection or bad light switch, there's not much to mess up on the headlight circuit.

Do you front parking lights work? When turning on the headlights there are two settings, halfway out and all the way out. Parking lights should only work when halfway out. At this point what about the rear lights, There's four circuits here, parking, brake, taillight and turn signal, but they all go through the same wires and all go through the turn signal switch.

Did everything work before you put the new harness in?

 

[A66Auto]

Thank you for the reply,

1- Yes everything did work before I swaped in the harness

2- I checked the harness from the fire wall forward and it was connected correctly and the only thing that looked funny was a dirty ground on the drivers side. I cleaned it up and reconnected and everything seems good.

3- My front parking lights do not work nor are my dash lights or courtsy lights, in fact the inst. panel and dome light fuses are blowing.

There are some wires that I don't know what to do with. They are not in the manual, may be they are for acc. I don't have.

This white and red one:

http://img227.imageshack.us/img227/940/whitered3kk.jpg

These two blury green and blue ones:
http://img164.imageshack.us/img164/4885/bluegreen1ou.jpg

And the furry one with the square connector, the white one with the female bullit connecter and the Black/red one witht he male bullit connecter:

http://img216.imageshack.us/img216/1202/blackred9xy.jpg

Thanks again,
Alex

 

[Tim65GT]

Maybe a PO changed the light switch to a different style and crossed a couple wires up?

Does the harness have a preformed plug for the light switch or individual terminals?

That's where I would start.

 

[A66Auto]

I bought a new switch just in case so I know that is correct. The harness plugs into the switch in one big plug.... I know it is something stupid.
I don't know anyone else with an old ford, let alone a mustang. So if any anyone can look at these parts and tell me if they look right:

Switch:
http://img158.imageshack.us/img158/2007/switch9yh.jpg

Harness plug:
http://img100.imageshack.us/img100/9383/harnessplug4jk.jpg

I may end up having to take it to a shop and have them fix it. I really don't want to do that.

 

[A66Auto]

looks like i am on my own

 

[Tim65GT]

Here is a pic that might help you troubleshoot:

Do the brake lights go off when you disconnect the brake light switch?

 

[A66Auto]

Thanks, I will double check that diagram...
The brake lights stay on when I disconnect the brake light switch,

Thanks again

 

[Tim65GT]

Are you sure it's your brake lights staying on, not your tail lights?

'cause you said "My brake lights and licenses plate lights are stuck on "

The licence pate light is wired to the tail lights in the back.

The more I read your symptoms, I think you have the wrong light switch or it's possibly plugged in wrong.

 

[A66Auto]

I think you are right that it is the tail lights and not the brake lights. The switch I had in there before looked pretty new but I replaced it just in case. I bought a brand new one from sacramento mustang and the same thing happened. All the wires going to the plug seem to match up what is in the diagram and the plug from the harness to the switch will only go one way. It is really starting to piss me off. Anyone have any more ideas where I should look?

 

[A66Auto]

Ok, I think you are on to something. I went out side and pulled my switch and compared it to the picture. If you look at what I drew, you will see that my switch looks like it is exactly 180 up side down. I mean, I wrote what is on my switch in blue letters and then I listed what color wires are comming out of that terminal.



The new and old switch are exactly a like. Is it possible that NPD gave me the wrong year harness? Are the 65-68 harness close enough to work? May be that is why I have some wires that are not on my diagram like:


This white and red one:

http://img227.imageshack.us/img227/940/whitered3kk.jpg

These two blury green and blue ones:
http://img164.imageshack.us/img164/4...uegreen1ou.jpg

And the furry one with the square connector, the white one with the female bullit connecter and the Black/red one witht he male bullit connecter:

http://img216.imageshack.us/img216/1202/blackred9xy.jpg

 

[Tim65GT]

I'm sorry; it looks like my diagram is flipped. I don't think your switch is backwards. What you put on the switch diagram in blue is correct. You may have the wiring crossed somewhere else.

I modified the diagram and added the factory wire color.

Do you have a wiring diagram?

Here is one for the exterior lights: http://www.hammar.dyndns.org/~djhamma/wiring/1966/66exter1.jpg

Here is one for the interior: http://www.hammar.dyndns.org/~djhamma/wiring/1966/66inter1.jpg

Use a voltmeter and the (correct) information you have so far and trace one circuit at a time.

I'm not familiar with the aftermarket wiring harnesses, but it's possible they have extra wires that are not used.

 

[1966conv]

I get some weird site when i try to view your pictures, but, the blury green ones sound like the courtesy light wires that go to the door switches.

 

[A66Auto]

After going racking my brain for the past week trying to figure out what I did wrong I looked that the NPD harness and realized that the plug that goes to the light switch is no wired correctly. What i mean is look at these and notice where the wires are on the switch.
(The images are hosted at image shack)

This is the old factory harness plugged in:

http://img520.imageshack.us/my.php?image=old12cl.jpg

This is the NPD harness:

http://img520.imageshack.us/my.php?image=new17pp.jpg

At this point NPD will not take it back and gave me the NAME of the vendor and nothing else. I bought it 8 days ago for 429.95 and now I am screwed and will not do business with them ever again.

So here are my options. I don't know how to get this fixed and NPD will not take back a defective product because I installed it. Is there a way to switch the plugs that go into the switch?