Starter switch 69 C500

[moparnutty]

Hi, Maybe someone on here smarter than me can tell me what would cause the blue wire with tracer on the back of the starter switch, to burn all the way to the firewall bulkhead. I'm replacing the dash wiring harness and would like to know what caused the short before trying to start the car.Just before the wire burnt the car would not start.Thanks

[nascarxx29]

http://www.1969chargerregistry.com/wiring.html .Link to wiring diagrams for your car Got any pictures of damage to investigate cause

[nascarxx29]

Blue with white tracer goes from Ignition switch.And to emergency brake warning light to bulkhead connector to the Ignition terminal on voltage regulator . Have any pictures to see what caused wire to melt.Also the hottest wire with little or no remaining plastic covering is the one to investigate.So if you can ad any details.We should be able to figure out what happened

[moparnutty]

Sorry for the bad pictures. I drove the car one day and it drove great. The next day it won't start. It would turn over but would not start.It was getting fuel but no spark.I jumped the resistor,still no start. I then had the wife to turn on the switch so I could check and see if I was getting volts at the coil.Soon as she turned on the switch smoke started to come out of the dash, so I pulled the battery cable off.After removing the switch I could see where the wiring harness had been taped just before the switch. All the wires looked ok except the blue wire with the tracer.It burnt all the way to the firewall.

[nascarxx29]

 It looks to be only that blue white wire that melted down for what reason?.Is there any other wires at key switch or underhood area that show damage including terminals on the bulkhead connection .The power to that blue white wire starts at rear of key switch.Then powers the emergency brake warning light on the far left side of the cluster. Then goes through the bulkhead.And powers the Ignition terminal that plugs into the voltage regulator.And powers the + pos of the coil thru the ballast circuit.

Did the emergency brake warning light ever work .Is that wire still intact also blue and white tracer and on same circuit.Did it get pinched and possibly shorted to ground Also you mentioned these Ignition switch plug wires were taped before.Last guy in there made a fix? .Dont know what he did or fixed or he had this same problem before.As you said it wouldnt start and had no spark .You lost power to pos + side of coil.And by passing the ballast didnt help .You just jumped the 2 sides of ballast together.Turned key and blue white wire cooked


It appears in the picture as that blue white wire shows melted plastic bare wire showing hottest point at backside of bulkhead.The problem may have originated under the hood.Is the same blue white wire on the other side of the bulkhead.As damaged how are the blue white tracer wire at the push on electrical connector on the voltage regulator.Any damages to wire at coil + postive terminal or wires on other side of the ballast

[moparnutty]

The blue wires with tracer in engine bay has no damage at all.The brake light blue wire also has no damage. The coil + blue wire looks good.Do you think I might have caused the damage when I jumped the ballast?Would a short in the starter switch cause this? Looks like someone spliced in another starter switch at some time.The only part of the blue wire that didn't burn is where it was taped.

[nascarxx29]

What did the firewall bulkhead connection look like in the front .As the blue white wire shown on backside melted.And where it plugged into bulkhead any damage there.Trying to isolate what areas recieved damage most to least.To see where it started at

[moparnutty]

Thanks NASCARXX29. The bulkhead connection on the engine side had no damage,and on the inside bulkhead connection also had little or no damage. The blue and white wire stopped melting when it got to the firewall bulkhead.I see some damage on the big black connector that the starter switch plugs into.The damage seems to be some melting of the connector on the plug-in side of the switch connector. It looks like the melting came from the red wire next to the blue and white wire. Also only the blue and white wire to the bulkhead melted even though the other blue and white wire that goes to the brake light came out of the same connection it was fine.Thanks for the help.

[moparnutty]

Bad voltage regulator was what caused the melt down. I replaced the regulator and added a 10 amp in-line fuse so maybe this won't happen again.I took it out for a ride today and everthing worked great.