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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Light problem

  • Thread starter Thread starter Purple
  • Start date Start date Oct 4, 2005
P

Purple

New Member
Oct 4, 2005
13
0
0
Oct 4, 2005
#1
  • Oct 4, 2005
  • #1
I have a 68 coupe that has a lighting problem. The turn signals and brake lights work with the headlights off, but once I turn the headlights on, all sorts of weird stuff happens. The small turn indicator arrows light up and the left rear brake/turn signal stops working. Would it be the headlight switch? Why would they work without the headlighte being turned on. I hope you can help because I got no response on another board.

Joe
 
T

ttoney

Member
Sep 12, 2005
195
0
16
Denver
Oct 4, 2005
#2
  • Oct 4, 2005
  • #2
I would change out that switch immediately. The is the easy test & fix. It is pretty cheap too.

There is a push button on the side of the switch you hold down, pull the lever out. It can take some effort, but it will com out. If you buy one first, it is easier to see the button so you can find it under the dash.

Unplug and inspect the connector and wiring that is connected to the switch. If it looks normal than buy a switch and replace. If it looks all jacked up, well then, wiring is probably going to need repair or replace.

Good luck.
 

rsev216

Member
Nov 17, 2003
109
0
17
Pinetop, Az
Oct 4, 2005
#3
  • Oct 4, 2005
  • #3
There are a lot of connections on the switch in very close proximity to each other. There is a good chance that something is shorted either in the switch or the connections to the switch. Pull the switch and examine it and the wiring carefully. I had parking lights come on with the headlights. It was a short between connections on the swithch.
 
6

66Runt

Member
Jun 11, 2005
680
2
18
Oct 4, 2005
#4
  • Oct 4, 2005
  • #4
Clean up all the ground connections

and make sure you have a good connection from Battery negative to the engine, and from the engine to the body of the car. There are several wires that ground to the chassis. Make sure they get a good bare metal to metal connection.

Scott
 

67coupe351w

New Member
Jan 31, 2004
424
0
0
Portland, OR
Oct 4, 2005
#5
  • Oct 4, 2005
  • #5
66Runt said:
and make sure you have a good connection from Battery negative to the engine, and from the engine to the body of the car. There are several wires that ground to the chassis. Make sure they get a good bare metal to metal connection.

Scott
Click to expand...

I agree, I had similar symptoms when installing a painless harness. It was fixed when the turn indicators were more properly grounded.
 
P

Purple

New Member
Oct 4, 2005
13
0
0
Oct 5, 2005
#6
  • Oct 5, 2005
  • #6
I will check the switch and connections asap. How many ground wires are there? If the turn indicator lights come on with the headlights, is there a ground wire under the dash?

Thanks
 

rsev216

Member
Nov 17, 2003
109
0
17
Pinetop, Az
Oct 5, 2005
#7
  • Oct 5, 2005
  • #7
On the 65 there is a ground wire right at the left turn signal/headlight assembly that needs a good ground. I don't think the lights get ground at the dash (other than dash/instrument lights).
 
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