No power at ignition switch.

[JimT]

I was installing the ignition switch on my 1965 Plymouth Valiant slant 6. It sparked against the dash (I realize I should have unhooked the battery). I do not have power to the ignition now. I have power from the battery to the fire wall. The horn works but the headlights do not work.

Where might my problem be?

Thanks for any advice,

Jim T

 

[67Dart273]

Probably blew up the fusible link at the firewall

 

[JimT]

Probably blew up the fusible link at the firewall

OK, thanks. What do they look like?

 

[CCHHAARRGGER!]

ok so, you need to proceed cautiously at this point. It sounds like the fusible link went bad. However I am concerned about the spark against the dash. This would not normally happen if the link died. The link is a small length of wire connecting to the bulk head connector in the engine compartment. The wire will usually have a tag that says fusible link, or the wire will have FUSIBLE LINK and the gauge of the wire printed directly on it. You must buy fusible link wire do not use regular wire. Fusible link wire is designed to give out so you do not fry anything else. Ask specifically for the one that works for mopars, trust NAPA, or a good local parts store, forget the other guys, they may try to sell you a fuse. However you must remove the dash cluster and inspect the red input wire going from the bulk head connector to the ammeter gauge. What you are describing sounds more like something is hitting the red ammeter positive wire. I have forgotten to tighten these before and yes they do create a nice spark if grounded. If anything is hitting this , you have a potential for a large fire. I have messed around with enough early a bodies where most have had either melted bulkhead connectors or wires with no plastic sheathing anymore because at some point they got really hot. The cars are notorious for having problems between the bulkhead connection and the ammeter gauge. The ammeter wire supplies power to the ignition switch which explains no power. Like I mentioned before be very careful and carefully inspect the red ammeter wire from the gauge to the inside of the bulkhead connection.
Here is a link for the wiring diagram
MyMopar - Mopar Forums & Information - Mopar Wiring Diagrams 1960 to 1965

Good Luck!

 

[CCHHAARRGGER!]

Here is a photo of typical fusible link

 

[TrailBeast]

OK, thanks. What do they look like?

Burnt.

Sorry, I couldn't stop myself.

These guys got ya taken care of.

 

[JimT]

ok so, you need to proceed cautiously at this point. It sounds like the fusible link went bad. However I am concerned about the spark against the dash. This would not normally happen if the link died. The link is a small length of wire connecting to the bulk head connector in the engine compartment. The wire will usually have a tag that says fusible link, or the wire will have FUSIBLE LINK and the gauge of the wire printed directly on it. You must buy fusible link wire do not use regular wire. Fusible link wire is designed to give out so you do not fry anything else. Ask specifically for the one that works for mopars, trust NAPA, or a good local parts store, forget the other guys, they may try to sell you a fuse. However you must remove the dash cluster and inspect the red input wire going from the bulk head connector to the ammeter gauge. What you are describing sounds more like something is hitting the red ammeter positive wire. I have forgotten to tighten these before and yes they do create a nice spark if grounded. If anything is hitting this , you have a potential for a large fire. I have messed around with enough early a bodies where most have had either melted bulkhead connectors or wires with no plastic sheathing anymore because at some point they got really hot. The cars are notorious for having problems between the bulkhead connection and the ammeter gauge. The ammeter wire supplies power to the ignition switch which explains no power. Like I mentioned before be very careful and carefully inspect the red ammeter wire from the gauge to the inside of the bulkhead connection.
Here is a link for the wiring diagram
MyMopar - Mopar Forums & Information - Mopar Wiring Diagrams 1960 to 1965

Good Luck!

ok so, you need to proceed cautiously at this point. It sounds like the fusible link went bad. However I am concerned about the spark against the dash. This would not normally happen if the link died. The link is a small length of wire connecting to the bulk head connector in the engine compartment. The wire will usually have a tag that says fusible link, or the wire will have FUSIBLE LINK and the gauge of the wire printed directly on it. You must buy fusible link wire do not use regular wire. Fusible link wire is designed to give out so you do not fry anything else. Ask specifically for the one that works for mopars, trust NAPA, or a good local parts store, forget the other guys, they may try to sell you a fuse. However you must remove the dash cluster and inspect the red input wire going from the bulk head connector to the ammeter gauge. What you are describing sounds more like something is hitting the red ammeter positive wire. I have forgotten to tighten these before and yes they do create a nice spark if grounded. If anything is hitting this , you have a potential for a large fire. I have messed around with enough early a bodies where most have had either melted bulkhead connectors or wires with no plastic sheathing anymore because at some point they got really hot. The cars are notorious for having problems between the bulkhead connection and the ammeter gauge. The ammeter wire supplies power to the ignition switch which explains no power. Like I mentioned before be very careful and carefully inspect the red ammeter wire from the gauge to the inside of the bulkhead connection.
Here is a link for the wiring diagram
MyMopar - Mopar Forums & Information - Mopar Wiring Diagrams 1960 to 1965

Good Luck!

 

[JimT]

Thanks.

 

[67Dart273]

ok so, you need to proceed cautiously at this point. It sounds like the fusible link went bad. However I am concerned about the spark against the dash. This would not normally happen if the link died. !

Don't understand what ????? If he touched one of the wires to a ground (dash) it would have sparked and possibly blown the fuse link. What were you thinking happened?

 

[CCHHAARRGGER!]

Don't understand what ????? If he touched one of the wires to a ground (dash) it would have sparked and possibly blown the fuse link. What were you thinking happened?

If you read my post carefully you would know what I m trying to help him with. If you replace the fusible link and something is touching the red ammeter wire ( remember he replaced his ignition switch), something may have moved behind the dash and the link will blow again or worse wont blow and instead the red ammeter wire will fry and potentially start a fire. If you re simply replacing an ignition switch why would that cause a spark behind the dash when you turn the key? Possible answers are faulty ignition switch, or something with power is touching ground, hence the blown fusible link. In my 30 plus years of working on everything from Desotos to Imperials to Miradas but mainly early a bodies I have seen many fusible links not blow and the red ammeter wire fry instead. I am only trying to help this guy through my experience dealing with similar issues, which I though this forum is all about. Maybe I am wrong, I just started to contribute to posts.

 

[TrailBeast]

If you read my post carefully you would know what I m trying to help him with. If you replace the fusible link and something is touching the red ammeter wire ( remember he replaced his ignition switch), something may have moved behind the dash and the link will blow again or worse wont blow and instead the red ammeter wire will fry and potentially start a fire. If you re simply replacing an ignition switch why would that cause a spark behind the dash when you turn the key? Possible answers are faulty ignition switch, or something with power is touching ground, hence the blown fusible link. In my 30 plus years of working on everything from Desotos to Imperials to Miradas but mainly early a bodies I have seen many fusible links not blow and the red ammeter wire fry instead. I am only trying to help this guy through my experience dealing with similar issues, which I though this forum is all about. Maybe I am wrong, I just started to contribute to posts.

The OP didn't say it sparked when he turned the key.
He said "I was installing the ignition switch on my 1965 Plymouth Valiant slant 6. It sparked against the dash (I realize I should have unhooked the battery). I do not have power to the ignition now. I have power from the battery to the fire wall. The horn works but the headlights do not work."

 

[CCHHAARRGGER!]

The OP didn't say it sparked when he turned the key.
He said "I was installing the ignition switch on my 1965 Plymouth Valiant slant 6. It sparked against the dash (I realize I should have unhooked the battery). I do not have power to the ignition now. I have power from the battery to the fire wall. The horn works but the headlights do not work."

and?

 

[TrailBeast]

and?

What are you asking me for?
You are the one helping him, and I just pointed out what he said about how it happened that was either misread or misunderstood.

But since you asked, he either blew the fusible link if the system is all stock then the bulkhead connector would be the next suspect, then the amp meter connections.
If it took more than that it would be any other connectors in the main power supply wiring or the wiring itself.

My personal bet is a 40+ year old fusible link.

 

[JimT]

The fusible link is hot into the fire wall (bulk head?). Ideas for the next place to check?

Thanks,

Jim

 

[CCHHAARRGGER!]

The fusible link is hot into the fire wall (bulk head?). Ideas for the next place to check?

Thanks,

Jim

Does the red ignition switch wire @ the ignition switch have power?

 

[JimT]

No power from the red wire at the ignition or any wire to the ignition.

 

[67Dart273]

Here is a simplified diagram of "that part" of the car. Do not take this diagram LITERALLY as some years changed a bit. But this gives you an idea of the main power distro:

The ammeter bypass article

Catalog

Diagram from the article

This is the functional path, not electron flow. Power comes off the battery and makes it's way to the "big stud" on the starter relay, which is one contact of the relay and also acts as a junction point

From the relay junction stud........to the FUSE LINK and through the BULKHEAD CONNECTOR

Keep in mind this is a CONNECTOR. If its' damaged, you could be losing power right there!!!

Then power (RED) goes to the AMMETER. That itself could have problems, bad/ corroded wire ends, loose nuts/ studs, or the internal parts, so you could be losing it there

After the ammeter, goes out on the big BLACK which goes BACK out through the firewall connector to the ALTERNATOR. See if you have power at the ALTERNATOR OUTPUT STUD

"Back up" a bit on the BLACK to the WELDED SPLICE. This is a splice up under the dash not far from the ammeter, where the wires are factory welded as shown THESE CAN, HAVE, and DO fail!!! Likely this is not the trouble here, but 'be aware' of it

IF YOU DO NOT hae a wiring diagram you need to go to MyMopar and download one. They have some years factory service manuals, as well as aftermarket wiring diagrams. Those diagrams are sometimes easier to follow than factory, but sometimes leave out connectors and options

MyMopar - Mopar Forums & Information - MyMopar Tools/Reference

 

[JimT]

Here is a simplified diagram of "that part" of the car. Do not take this diagram LITERALLY as some years changed a bit. But this gives you an idea of the main power distro:

The ammeter bypass article

Catalog

Diagram from the article

View attachment 1715190169

This is the functional path, not electron flow. Power comes off the battery and makes it's way to the "big stud" on the starter relay, which is one contact of the relay and also acts as a junction point

From the relay junction stud........to the FUSE LINK and through the BULKHEAD CONNECTOR

Keep in mind this is a CONNECTOR. If its' damaged, you could be losing power right there!!!

Then power (RED) goes to the AMMETER. That itself could have problems, bad/ corroded wire ends, loose nuts/ studs, or the internal parts, so you could be losing it there

After the ammeter, goes out on the big BLACK which goes BACK out through the firewall connector to the ALTERNATOR. See if you have power at the ALTERNATOR OUTPUT STUD

"Back up" a bit on the BLACK to the WELDED SPLICE. This is a splice up under the dash not far from the ammeter, where the wires are factory welded as shown THESE CAN, HAVE, and DO fail!!! Likely this is not the trouble here, but 'be aware' of it

IF YOU DO NOT hae a wiring diagram you need to go to MyMopar and download one. They have some years factory service manuals, as well as aftermarket wiring diagrams. Those diagrams are sometimes easier to follow than factory, but sometimes leave out connectors and options

MyMopar - Mopar Forums & Information - MyMopar Tools/Reference

Thanks a bunch! With all the help from all of you I feel I should have it up and running soon. Good info.
Thanks again,
Jim

 

[KosmicKuda]

In my experience, sparking or arcing when installing something in a live circuit usually leads to a blown fuse or tripped circuit breaker. Whether messing around with house or car wiring. Having no power after that is a dead giveaway. I doubt mechanical connections are going to suddenly go bad if they were ok before that.

If that happened to me the first thing I would think of checking is the fuses in the fuse box.

Next would be the fusible link which looks pretty much like a wire spliced into the loom in the vicinity of the bulkhead connector. It acts like a fuse because it is a smaller gauge wire that burns out when overloaded to save the main wiring and hopefully prevent a fire.

You can also check the bulkhead connector that passes through the firewall. (Looks like a rectangular plastic block on the firewall with a bunch of wires going into it to the left of the master cylinder) The contacts for the heaviest black and red wires are notorious for causing problems as they were not the best choice to carry that much power. As they age and get dirty, the resistance goes up and generates heat which melts the plastic and wires. You can carefully unplug the engine side of the block and inspect them in both halves of the plug.

 

[67Dart273]

If bla bla bla.

Why didn't you just SAY that? I was merely asking you "where you were going" and "where you were coming from?" You could have said "proceed cautiously as the short may still be in place."

I was confused by your post, and was merely asking what you were thinking. OK? Well, OK then!!