New H/L switch, same problem.
Thread Starter
Racer
Joined: Apr 2011
Posts: 391
Likes: 69
From: Toronto , Ontario
New H/L switch, same problem.
Last week l posted about no dash lights.Got my second new switch.Dash harness is new ,ground is good,bulbs are good,put a jumper wire red to green on the harness and power going to the fuse box and dash lights come on. So far so good. Install new switch and the same thing.Dome,parking and headlights work but no power to the green wire going the the fuse to engage the dash lights. The switch does have a tab on the side so you could add an extra ground wire but if 3 of the 4 functions work ,ground must be good. WTF can it possibly be another bad H/L switch. I,m pissed about this simple repair, could use some direction before l send both switches back. By they way l also bench tested the switch with a test light and didn,t get a reading off the green tab. Any help would be greatfull. Elio
Safety Car
Joined: Nov 2007
Posts: 4,488
Likes: 805
From: East Central Florida
After reading your other thread......here
Tail lights working? TL fuse okay?
I'm looking at the '64 schematics and I believe the Brown wire from the Tail Light fuse feeds the Dk Green Dash light circuit at the HL switch. Check for 12v at the Brown wire at the HL switch. It's the outer Brown terminal.
The pic below shows a 64-67 switch, but the wire colors are for 67. Orange is the feed. This is where to check for 12v from the TL fuse.
There are 2 Brown wires at your switch. The other one goes to the tail lights. Also make sure your **** is fully CW to bypass the dimmer.
For '67 the Brown feed changed to Orange, sourced from the Brake Light circuit rather than the Tail circuit. But 64 to 67 use the same HL switch.
Tail lights working? TL fuse okay?
I'm looking at the '64 schematics and I believe the Brown wire from the Tail Light fuse feeds the Dk Green Dash light circuit at the HL switch. Check for 12v at the Brown wire at the HL switch. It's the outer Brown terminal.
The pic below shows a 64-67 switch, but the wire colors are for 67. Orange is the feed. This is where to check for 12v from the TL fuse.
There are 2 Brown wires at your switch. The other one goes to the tail lights. Also make sure your **** is fully CW to bypass the dimmer.
For '67 the Brown feed changed to Orange, sourced from the Brake Light circuit rather than the Tail circuit. But 64 to 67 use the same HL switch.
Team Owner
Joined: Jul 2006
Posts: 22,164
Likes: 4,171
From: Kannapolis NC
There are two 12v dc sources to the headlight switch. The brown wire that comes from the second fuse from the bottom for the tailights and the red wire from the unfused 12v and goes directly to the headlight switch and then to the third fuse from the bottom marked instr lmps. You should have 12 v on both sides of both the second and third fuses from the bottom and also on the brown and red wires at the headlight switch. MEASURE for 12v on both sides of both fuses and post back.
You know inst panel ground is good or the dash lights wouldn't have lit up when you shorted 12v to the green wire, and you know the bulbs are good. The only place to get 12v on the green wire is through the switch. I don't think you have 3 bad switches. The only thing that makes sense to me is either missing the voltage at the fuse or wiring from the fuse box to the headlight switch.
You know inst panel ground is good or the dash lights wouldn't have lit up when you shorted 12v to the green wire, and you know the bulbs are good. The only place to get 12v on the green wire is through the switch. I don't think you have 3 bad switches. The only thing that makes sense to me is either missing the voltage at the fuse or wiring from the fuse box to the headlight switch.
Thread Starter
Racer
Joined: Apr 2011
Posts: 391
Likes: 69
From: Toronto , Ontario
Well good morning,used a tester and found this out.Worrying about my dash lights l never noticed that i had no tale lights neither ,in the park position.Bottom two fuses are hot on both sides,third fuse no power out board side,checked the brown wire at the rear harness connection and no power,pulled the H/L switch out from the dash and still connected to the harness and no power on either two of the brown wires, but the red is hot. Now all wiring new from last year,never had this problem a month ago and no work was done to screw up something.The H/L switch functions front parking lights,courtesy and head lights.What doesn,t work are the rear tail lights and dash lights.By the way l tested all connections with ignition switch in different positions. Were to go now? Thanks Elio
Thread Starter
Racer
Joined: Apr 2011
Posts: 391
Likes: 69
From: Toronto , Ontario
Looking at the back side of my old dash harness fuse box and the wiring diagram could it be possible that the new harness brown wire coming from the inboard side of tail lamp fuse and going to the rear harness connector has via H/L switch be broken internally. Same original fuses put in with new harness.No fuses have been blown to change.
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Tech Contributor
Joined: May 2005
Posts: 15,576
Likes: 118
From: Conroe Texas
Try replacing the tail lamp fuse.
If the tail light fuse blows, the dash lamps will also go out as some sort of safety measure (lets you know you have no tail lamps).
It is possible your fuse looks good, but is no longer completing a circuit.
If the tail light fuse blows, the dash lamps will also go out as some sort of safety measure (lets you know you have no tail lamps).
It is possible your fuse looks good, but is no longer completing a circuit.
Safety Car
Joined: Nov 2007
Posts: 4,488
Likes: 805
From: East Central Florida
Okay, no tail lights. Makes sense now.
Yes it appears you have a open between the Tail lamp fuse and the outer brown terminal to the headlight switch. I'd suspect a break at the back of the fuse clip. You may want to pull your bulkhead connectors and pull the fuse block to check. Disconnect battery first.
If that is okay, then you have a open in the harness. Also check that the brown terminal at the HL switch is properly crimped. You may want to remove the terminal from the plastic plug to verify.
Yes it appears you have a open between the Tail lamp fuse and the outer brown terminal to the headlight switch. I'd suspect a break at the back of the fuse clip. You may want to pull your bulkhead connectors and pull the fuse block to check. Disconnect battery first.
If that is okay, then you have a open in the harness. Also check that the brown terminal at the HL switch is properly crimped. You may want to remove the terminal from the plastic plug to verify.
Thread Starter
Racer
Joined: Apr 2011
Posts: 391
Likes: 69
From: Toronto , Ontario
Well i,m back. Pulled fuse box and its ok. pulled out brown wire from switch harness ajusted tang and its ok. Now l have rear parking lights and there is power to both brown wires at the harness, H/L switch. So l took off the green wire off at the connecter ajusted the tang installed H/L switch and still no power coming out from the green to panel fuse. I tested all this with the switch hanging so l guess the metal casing is not a ground ? Now What?
Safety Car
Joined: Nov 2007
Posts: 4,488
Likes: 805
From: East Central Florida
Well i,m back. Pulled fuse box and its ok. pulled out brown wire from switch harness ajusted tang and its ok. Now l have rear parking lights and there is power to both brown wires at the harness, H/L switch. So l took off the green wire off at the connecter ajusted the tang installed H/L switch and still no power coming out from the green to panel fuse. I tested all this with the switch hanging so l guess the metal casing is not a ground ? Now What?
If Brown at the switch now has 12v, and if Dk Grn does not with switch on, are you sure the dimmer/**** is turned CW? If so, it's possible you're losing the Brown feed due to a intermittent open between the fusebox and HL plug. Wiggle it around while testing it.
The ground is ONLY used for the courtesy light operation from the HL switch. It has no effect on other lighting operations.
Last edited by rich5962; Nov 18, 2012 at 02:23 PM.
Thread Starter
Racer
Joined: Apr 2011
Posts: 391
Likes: 69
From: Toronto , Ontario
rich5962,65GGvert and others, THANK YOU for the help. Every thing is working as it should.Between the brown wire at the switch needing a little tweeking and finding the sweet spot on the new switch for dash lights l can now put the car into storage , after a good run,and put hours of trouble shooting behind me.Thanks again guys for your help. Elio 
