Wiring woes

Tonybkel@newulmte

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Hooked up power to the 68 vert today and had no parking lights, had headlights but no parking lights. in the process of troubleshooting the headlight switch I put 12 volts to the yellow wire on the dash dimmer switch plug trying to see if I could get park lights to come on. smoked the yellow wire going to the drivers door acc light switch, checked the switch afterwards and it checks out fine with a conductivity meter. Possible direct short on the wire going to the switch? Thoughts?, also have question on pertronix points replacement. diagram shows that car with coil ballast resistor, the red wire needs to be hooked into the wiring on the 12 volt side of the resistor. That being said, what have others done in regards to getting it hooked into the wiring prior to the resistor, where and how did you connect it? I was wondering if I could just get 12 volts from the alternator 12 volt post? any help would be appreciated. this project would have been a lot easier if you could buy dash harnesses, but had to repair many cut or cracked wires. Not rocket science but a lot of time.
 
Did you have tail lights? Check fuse for tail lights. That comes from the fuse panel to the light switch. There are two power wires to the light switch. One non fused for the headlights and one fused for the tail lights, which may also power the park lights (I don’t have a switch schematic to tell for sure) large Black wire with tracer at switch is battery power and pink is fused power in. use a test light to make sure both power wires have power. Then turn your switch on to see if your yellow wire has power. The smaller black wire is for your tail lights. Make sure your switch is functional first.
The lights do not have a separate ground so if newly installed or not touched in years they may not be getting ground if your switch seems to be working. Use your test light and work from the switch to the light to se where the power stops.
If power is all the way to the light your ground is probably bad.
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Your ballast resistor should have 2 wire terminals, one terminal has a dk blue wire and the other terminal has a dk blue wire and a brown wire. The single dk blue wire should be 12v from the ignition switch, this is the one you want for the 12v source for your pertronix.
 
The headlight switch has an internal circuit breaker as a safety device. Too much resistance in the circuit trips the breaker. If it is compromised/worn, you lose the headlights.

My black 2DHT had this issue. Sometimes the headlights would just shut off while driving. If I played with the switch, I could get them to come back on for a while, but eventually the switch gave out completely.

Hope the input helps.

John
 
Just a reminder the front park lights do not come on with headlights.
Park lamps run on a fuse that other circuits may share.
There are no reproduction c body wire harness.
That being said get a FSM. with the wiring diagrams.
The yellow wire at dimmer you smoked has nothing to do with park lamps. Making more work for yourself for no reason.
I prefer to do continuity tests with a multi meter and not use the car's power source simply for avoiding any further back feeds or shorts.
Park lamps are a switched source- dimmer switch has power to it all the time.
Hope this helps.
 
Hooked up power to the 68 vert today and had no parking lights, had headlights but no parking lights. in the process of troubleshooting the headlight switch I put 12 volts to the yellow wire on the dash dimmer switch plug trying to see if I could get park lights to come on. smoked the yellow wire going to the drivers door acc light switch, checked the switch afterwards and it checks out fine with a conductivity meter. Possible direct short on the wire going to the switch? Thoughts?, also have question on pertronix points replacement. diagram shows that car with coil ballast resistor, the red wire needs to be hooked into the wiring on the 12 volt side of the resistor. That being said, what have others done in regards to getting it hooked into the wiring prior to the resistor, where and how did you connect it? I was wondering if I could just get 12 volts from the alternator 12 volt post? any help would be appreciated. this project would have been a lot easier if you could buy dash harnesses, but had to repair many cut or cracked wires. Not rocket science but a lot of time.

Down load the wiring diagram for free at www.mymopar.com
The wiring diagram is in the Tools/Reference section. The push button door switch as an example provides a ground to the circuit, not power. Hooking power to a ground leg will smoke it every time. Some interior lighting is activated by completing a ground, not supplying power.

Dave
 
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A lot of good information, I have a manual, I ordered the colored version as I used one for my 66 b body, the version for the c body was incorrect in the color of wires I looked at when I had the dash on the bench and sent it back. I checked the door switch and it tests fine with a meter. it was my fault as I jumpered from the black wire with tracer to the yellow wire on the switch connector. The information on the pink wire is good and I will check but I did not have power to any but the black with tracer. I will start there today and see, good thing is the only wire that needs repair is the yellow, nothing else was damaged other than my pride. Dash is taken apart and I can fix the yellow without taking the dash out again as the new windshield is installed. I can also better check the switches and replace if needed with the cluster out. When I started this job I did not expect so many issues with wiring but here we are, no replacements but manual with good diagrams and many resources on this website that have been more than willing to help out. I appreciate all the help and will keep updating. Thanks.
 
Got everything back together this afternoon headlights,parking lights, turn signals all work. Replaced bad wire that went to the dome light switch on the drivers door and replaced the headlight switch. Thanks for all the help. Pertronix wire tomorrow. attached some pics.
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White interior and top on the way.
 
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