I Have a Problem With My 1975 Plymouth Duster

It is a 225 slant 6 auto. There was an electrical issue going on leaving the light on even when there was no key in the ignition(windshield leak is a probable cause for the issue). Plus I could not start the car by turning the key, I had gone straight to the starter to turn it over and it turns over (I replaced the starter when I bought the car). So I started replacing some of the old electrical components, (headlight dimmer switch, starter relay, starter resistor, and a few replacement electrical components and the problem still persisted. So then I decided to pull the gauge cluster out and found my on/off/driving light switch was corroded and a few bulb sockets were missing. Replaced those reinstalled my gauge cluster to which I know I can't even turn the car over and the lights that previously worked didn't. So I am a little stumped and was wondering if anyone has an idea to what maybe the problem. All help greatly appreciated! Thanks in advance.

Have you performed any more testing?
I would suggest concentrating on one system, preferably the reason the starter doesn't turn over the engine. Get a wiring diagram and, checking voltage while a helper tries cranking with the key, see if the starter relay is getting a signal from the ignition switch.
Likely a connection problem. Maybe the bulkhead connector at the firewall.
Get some test results and post an update.

Bobzilla said:

Have you performed any more testing?
I would suggest concentrating on one system, preferably the reason the starter doesn't turn over the engine. Get a wiring diagram and, checking voltage while a helper tries cranking with the key, see if the starter relay is getting a signal from the ignition switch.
Likely a connection problem. Maybe the bulkhead connector at the firewall.
Get some test results and post an update.

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I would be looking at your ignition switch. No your key and tumbler. But your actual ignition switch. .

So, now you have no power at all? No lights? Not really familiar with the 75 model. Do they have a fusible link? Or a fuse??

You could have shorted something when you pulled out the gauge cluster. Always best to disconnect the battery when working on electrical.

66fyssh said:

So, now you have no power at all? No lights? Not really familiar with the 75 model. Do they have a fusible link? Or a fuse??

You could have shorted something when you pulled out the gauge cluster. Always best to disconnect the battery when working on electrical.

Click to expand...

I did disconnect the battery when I pulled the gauge cluster. yes no lights and 2 fuseable links I've seen but 1 is fixed and the other look fine.

66fyssh said:

So, now you have no power at all?

Click to expand...

Not that I can find, fuses are good as well. I'll try to see if there is power to the steering column tonight.

Two fusible links is an indication that your system is not quite the same as most of the previous years, or yours came with an option with a different wiring.
The best diagrams will be in the '75 factory service manual. Posting photos may help too.

That said..
engine off...key off..
Power from the battery will be available to everything in the main circuits and the circuits that are always hot:
This includes the headlights - that are on circuit breaker (terminal B1 on your switch)
It includes half of the fuse box, including the fuse(s) for the dome, hazzard, parking and stop lights.

So. With voltmeter or test light, follow the power feed(s) from the battery. Each junction should be at battery voltage. You can do a check at the Alternator output stud (usually marked Batt on the casting) since its connected.
It may pass this check (battery voltage each junction) and still have poor connections, but its a good way to look for a break.

The basic scheme '73 (through?) is like this. (not shown is the ignition switch connector but its important)