64 Plymouth Barracuda new switch yet headlights still won't come on

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64Barracudaowner

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Replacing a frozen headlight switch restored parking and dash lights but not the headlights. Headlamps light when wired directly to battery -- both high and low beam. Have cleaned all gang connectors under dash and at fire wall. Checked and cleaned fuse contacts and confirmed conductivity across the glass under-dash fuses. Any suggestions? Fuel gauge is also not working with a new in-tank sender unit -- I don't know if the problems are related. Thanks for any help.
 
Headlights don't go through a fuse. There are two battery sources for the headlight switch. One supplies park/ tail/ instrument lighting, and the headlights (be careful!!) comes UNFUSED branched off from what is called "the welded splice. This is a big splice in the black ammeter wire up in the under-dash harness. Look at the wiring diagram, they show that.

Easiest to start at the dimmer switch and check there. Your functional power path is.............from welded splice.............to headlight switch.........through switch.........out on headlight supply wire...........to dimmer switch............out to either one or other brights or dim.

Try cycling dimmer switch while watching high beam indicator.......if indicator lights, you have power OUT of the dimmer switch

From the dimmer, power goes through your bulkhead connector on brights and on dims wiring, to light harness "out front"

CHECK THE LIGHTS GROUND. There might be only one ground......which screws to the radiator support
 
67Dart273 said:
Headlights don't go through a fuse. There are two battery sources for the headlight switch. One supplies park/ tail/ instrument lighting, and the headlights (be careful!!) comes UNFUSED branched off from what is called "the welded splice. This is a big splice in the black ammeter wire up in the under-dash harness. Look at the wiring diagram, they show that.

Easiest to start at the dimmer switch and check there. Your functional power path is.............from welded splice.............to headlight switch.........through switch.........out on headlight supply wire...........to dimmer switch............out to either one or other brights or dim.

Try cycling dimmer switch while watching high beam indicator.......if indicator lights, you have power OUT of the dimmer switch

From the dimmer, power goes through your bulkhead connector on brights and on dims wiring, to light harness "out front"

CHECK THE LIGHTS GROUND. There might be only one ground......which screws to the radiator support
Click to expand...
67Dart273 said:
Headlights don't go through a fuse. There are two battery sources for the headlight switch. One supplies park/ tail/ instrument lighting, and the headlights (be careful!!) comes UNFUSED branched off from what is called "the welded splice. This is a big splice in the black ammeter wire up in the under-dash harness. Look at the wiring diagram, they show that.

Easiest to start at the dimmer switch and check there. Your functional power path is.............from welded splice.............to headlight switch.........through switch.........out on headlight supply wire...........to dimmer switch............out to either one or other brights or dim.

Try cycling dimmer switch while watching high beam indicator.......if indicator lights, you have power OUT of the dimmer switch

From the dimmer, power goes through your bulkhead connector on brights and on dims wiring, to light harness "out front"

CHECK THE LIGHTS GROUND. There might be only one ground......which screws to the radiator support
Click to expand...
I am not sure I understand what you mean by dimmer switch but let me tell you what I did.
I pulled the switch shaft to the headlight "on" position. No headlight. I rotated the knob and noted that dash lights dim and go out. I rotated the knob so that dash lights were again visible. I depressed foot switch that would normally engage the high beams. No high beam and no high beam dash indicator light (no guarantee this indicator light works --although most do).
Regarding ground --I think you are correct there seems to be only one ground and I will clean it. However, would I have been able to hot wire the headlamps if the ground was faulty? Many thanks.
 
64Barracudaowner said:
I am not sure I understand what you mean by dimmer switch but let me tell you what I did.
I pulled the switch shaft to the headlight "on" position. No headlight. I rotated the knob and noted that dash lights dim and go out. I rotated the knob so that dash lights were again visible. I depressed foot switch that would normally engage the high beams. No high beam and no high beam dash indicator light (no guarantee this indicator light works --although most do).
Regarding ground --I think you are correct there seems to be only one ground and I will clean it. However, would I have been able to hot wire the headlamps if the ground was faulty? Many thanks.
Click to expand...
 
you have any money. you fix one prop then u have.?. u want 2 keep wiring harness on any mopar sucks burns or used out. take this to your ?... rewire the section u YOU ur great. common sense an the reason u you own a mopar is fix... fix is new wiring harness u replace. its old. old. if is or was there will you sleep. R U A keeper of all 4 some time. just replace that.. portion of harness. clean all of other related. water moisture,nasty. only way 4 a complete repair u fix if bad u still unhappy sale car.. they will fix and cheep.
 
if all is new. tell me a 50yrowner of all mopars agood selecton of them. ***** and complain but not here cars r cars sell I want u r car. old s what I as a new member to this site. you get great advice use it or run. mopars that r old need dollars spent as you do on self help. sell walk back inside home AND SAY U EVER OWNED A MOPAR.... good night oh I made dollars on your. stop leave mopar. by...….
 
The dimmer @67Dart273 is referring to the headlight hi/lo dimmer switch, not the dash light dimmer. Just follow the path he laid out. The dimmer switch is a good place to "split" troubleshoot. Check for voltage in/out of the dimmer switch. If you don't have voltage in, you know the problem is before. If you have voltage out, you know the problem is after the dimmer switch.
 
charles mill said:
if all is new. tell me a 50yrowner of all mopars agood selecton of them. ***** and complain but not here cars r cars sell I want u r car. old s what I as a new member to this site. you get great advice use it or run. mopars that r old need dollars spent as you do on self help. sell walk back inside home AND SAY U EVER OWNED A MOPAR.... good night oh I made dollars on your. stop leave mopar. by...….
Click to expand...
I got news for you,Bud. It aint just mopars.
At 50 plus years old, wiring breaks and switches fail. Terminals corrode and stuff just falls apart. Its the nature of the beast.
I see op started a second thread, a good test light will serve you very well in tracking down your problem.
 
point and may I and god say what I saw on as a mopar reply on 64 cuda. u did was a disrespect to your 64. old as you get a year one harness and / and coat all connections with what. silicone grease cheap/ hi dollar. you use so I. I. donot see a complaint at this point you came to this site for help did you find another or . who helped us both. this site man your harness and b proud u r not on side of road.
 
that was not cool me making last stament. to get I show.cars replace a harness or part you can buy. stop I have a second owner 68 fastback b5 blue barracuda. have shown n ks city several times. b5 blue is a good color interior is purl white. one repair saves money looking to find a way 2 repair. I me have a ford paper that was at a meeting gave to me. said I honored them. for 25 years. I drove 73 dart and a jeep every day I worked on.
 
66fyssh said:
The dimmer @67Dart273 is referring to the headlight hi/lo dimmer switch, not the dash light dimmer. Just follow the path he laid out. The dimmer switch is a good place to "split" troubleshoot. Check for voltage in/out of the dimmer switch. If you don't have voltage in, you know the problem is before. If you have voltage out, you know the problem is after the dimmer switch.
Click to expand...
Thanks, that helps.
 
67Dart273 said:
Headlights don't go through a fuse. There are two battery sources for the headlight switch. One supplies park/ tail/ instrument lighting, and the headlights (be careful!!) comes UNFUSED branched off from what is called "the welded splice. This is a big splice in the black ammeter wire up in the under-dash harness. Look at the wiring diagram, they show that.

Easiest to start at the dimmer switch and check there. Your functional power path is.............from welded splice.............to headlight switch.........through switch.........out on headlight supply wire...........to dimmer switch............out to either one or other brights or dim.

Try cycling dimmer switch while watching high beam indicator.......if indicator lights, you have power OUT of the dimmer switch

From the dimmer, power goes through your bulkhead connector on brights and on dims wiring, to light harness "out front"

CHECK THE LIGHTS GROUND. There might be only one ground......which screws to the radiator support
Click to expand...
 
Two questions how can I tell which switch wire is the headlight supply wire that goes to dimmer switch. I guess I can try to backtrack from the dimmer switch yet I hope that is not the only way. Also, where can I find a wiring diagram for a 64 Barracuda? Thanks
 
Poke the probe for your test light or volt meter onto the backside of the dimmer switch connector of the light green wire with the headlight switch on. If you have no power there probe the headlight switch at the terminal with the light green wire (H terminal). If there is power at the dimmer switch check the red and black to verify continuity through the dimmer.
 
64Barracudaowner said:
Two questions how can I tell which switch wire is the headlight supply wire that goes to dimmer switch. I guess I can try to backtrack from the dimmer switch yet I hope that is not the only way. Also, where can I find a wiring diagram for a 64 Barracuda? Thanks
Click to expand...

Go to MyMopar. They have shop manuals and wiring diagrams for free.

The dimmer is easy. You only have three wires. At any time with the light switch on, TWO of them should be hot, that is, the headlight "on" power comin into the switch, and one of the outfeeds to either low or high beam. Switching the dimmer should result in the dead wire coming alive, and one of the other two going dead
 
67Dart273 said:
CHECK THE LIGHTS GROUND. There might be only one ground......which screws to the radiator support
Click to expand...

Or in the case of an early A there is a separate ground for each headlight. The ground is inside the bucket in back of the headlight.
 
Wow!
A lot of responses for you on this one.
Let me ask:
Is the headlight switch new?
67dart is correct, the headlights don't go through the fuse box, but the switch could be faulty.

We've established that it is properly grounded.
Two things to look at . First is the fuse-able link on the firewall , I believe if it blows that it will take out the headlights.
Second thing in the "ampmeter". These are notorious for burning out or even burning up. You can bypass it by it by connecting the two wires together...DISCONNECT THE BATTERY FIRST.

Your fuel gauge:
The new tank sending units that you can get have their issues, but the problem is likely in the dash. There's a voltage limiter in the cluster that drops the current to 5.5 volts for the fuel gauge. With a little thought and examination, you can "bench test" it. Look at the printed circuit board to follow the current path to the gauge, grounding .........maybe we get you through the headlights first.

I have a complete 64 Barracuda gauge cluster, if needed
 
Michael Brisebois said:
Wow!
A lot of responses for you on this one.
Let me ask:
Is the headlight switch new?
67dart is correct, the headlights don't go through the fuse box, but the switch could be faulty.

We've established that it is properly grounded.
Two things to look at . First is the fuse-able link on the firewall , I believe if it blows that it will take out the headlights.
Second thing in the "ampmeter". These are notorious for burning out or even burning up. You can bypass it by it by connecting the two wires together...DISCONNECT THE BATTERY FIRST.

Your fuel gauge:
The new tank sending units that you can get have their issues, but the problem is likely in the dash. There's a voltage limiter in the cluster that drops the current to 5.5 volts for the fuel gauge. With a little thought and examination, you can "bench test" it. Look at the printed circuit board to follow the current path to the gauge, grounding .........maybe we get you through the headlights first.

I have a complete 64 Barracuda gauge cluster, if needed
Click to expand...
Thanks for your help. I got into the wiring leading to the floor dimmer switch from the headlight switch and tried to remove the connector from the switch. The dimmer switch came apart as I pulled on the connector. I cleaned the contacts and did a quick hot glue gun fix and headlights came on! I am off to the parts store to replace the dimmer switch. Thanks for everyone's help. Fuel gauge will be another day's challenge! It may be just a matter of insufficient gas in the tank to register on the gauge. Off to the gas station...
 
Glad you found the issue!!

Search around the site when you are ready to tackle the fuel gauge. There are many threads on it. I had to retrofit my 66 with a digital internal voltage regulator (replacing the factory one inside the fuel gauge). These old girls are really fun to work on!!!
 
64Barracudaowner said:
Thanks for your help. I got into the wiring leading to the floor dimmer switch from the headlight switch and tried to remove the connector from the switch. The dimmer switch came apart as I pulled on the connector. I cleaned the contacts and did a quick hot glue gun fix and headlights came on! I am off to the parts store to replace the dimmer switch. Thanks for everyone's help. Fuel gauge will be another day's challenge! It may be just a matter of insufficient gas in the tank to register on the gauge. Off to the gas station...
Click to expand...

Dimmer switches are still available at parts stores and are not expensive. Get the "better quality" spread, tho.

See? this stuff ain't hard LOL
 
Michael Brisebois said:
Wow!
A lot of responses for you on this one.
Let me ask:
Is the headlight switch new?
67dart is correct, the headlights don't go through the fuse box, but the switch could be faulty.

We've established that it is properly grounded.
Two things to look at . First is the fuse-able link on the firewall , I believe if it blows that it will take out the headlights.
Second thing in the "ampmeter". These are notorious for burning out or even burning up. You can bypass it by it by connecting the two wires together...DISCONNECT THE BATTERY FIRST.

Your fuel gauge:
The new tank sending units that you can get have their issues, but the problem is likely in the dash. There's a voltage limiter in the cluster that drops the current to 5.5 volts for the fuel gauge. With a little thought and examination, you can "bench test" it. Look at the printed circuit board to follow the current path to the gauge, grounding .........maybe we get you through the headlights first.

I have a complete 64 Barracuda gauge cluster, if needed
Click to expand...

Isn't the '64 IVR inside the fuel gauge? I forget...............
 
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