The car runs great except for it just had the battery light come on bright. This was after I parked it for 15 minutes with no issues prior. The tachometer barely works a little but not as it should and only when slowing down. The temp and gas gauge are dead. The speedometer is fine. My little (turbo style) volt meter is dead. All wires on the back of the alternator appear to be fine. My turn signals are not working unless its just the dash and sound that are dead. Headlights work fine.

Alternator is giving 12.something volts which is below the 13.8 I believe it should. I'm going to switch out the alternator with a spare I have. I know the brushes are not that old unless one broke or something.

My warning lights the past few months only showed the oil light when turning the ignition. Any chance this is related or should I be looking at the ignition switch as well?

Roll fuse 13.
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Art Benstein near Baltimore

There is no psychiatrist in the world like a puppy licking your face.
-Ben Williams

Thanks Art. Ended up being a very difficult to see broken fuse.

I rolled it and gave it a look a couple days ago and couldn't see the break. In the process I swapped out the alternator and ignition switch with good used spares on hand. I switched out the alt before reading on Gunga din's thread that I could test it by jumping the alternator excite wire. That thread was interesting to read. I learned some things that were missing from my skill set.

After I replaced the ignition switch today and it still didn't work. I used a light to look closer at the fuse and must have broken from age. Then again could I have broken it while twisting and the ignition switch needed replacing since the cluster lights other than my oil was lighting up for the past month or two? Either way cracked fuses are tough to see sometimes.

Certainly it could have been the contacts in the ignition switch. However, the fuse is the place to start, and electrics sometimes refuse to be visually diagnosed.

"Ended up being a very difficult to see broken fuse."

The fuse at the top of this picture is the only one a reasonably well-sighted person could call out visually.



The one in the center is what I think you found. It is work-hardened when it expands and contracts passing an appreciable amount of its rated current in the circuit, on and off. The brake light fuse is often cracked like this. As you can imagine, the broken ends will touch sometimes, making the problem come and go.

If the crack was at the end, that might have occurred by handling.

The one at the bottom is typical with the corrosion at the ends due to moisture and dissimilar metal. All 240 owners learn to roll the fuse to temporarily regain the connection, I think.

And these fuses, really, should be done away with, and replaced by brass or copper fuses, readily available today.

But to diagnose visually is hit or miss. The only true way to test a fuse...



If the ignition switch were faulty, and you were catching it being faulty, your probe would not find battery voltage on the left side contact brass either.

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Art Benstein near Baltimore

A man walks into a bar with a slab of asphalt under his arm and says: "A beer please, and one for the road."

Thanks for the info on testing fuses.

I spoke too soon because I went out tonight and found the warning lights did not light up only the oil warning light worked with at start. I checked the fuse and it looked good but when I get a chance I'll swap it out and test it as you've shown. My small voltage gauge was working this time. My fuel and temp were working this time as well. Those three didn't work last time before I started to fix it.

I have a spare instrument cluster that I can try in an attempt to eliminate it as a problem. Seems a bit strange to have worked after replacing the ignition switch and fuse.

Granted it could, by some remote likelihood, be a problem with the connector on the instrument panel, but there's only one fuse (13) responsible for your symptoms, and nothing under the hood. The usual cause is crud in the fuseholder, hence the advice to "spin" the fuse. Checking for power there will tell you the truth.
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Art Benstein near Baltimore

"I am." is the shortest complete sentence in the English language.

Worked first thing today. Going with lightly cleaning contacts and replacing fuses. Yhanks for your guts help.
*engine harness was upgraded/replaced.

First: before you go tearing any further into it, Replace All the Fuses --- cheap and easy.

Second: have you replaced and/or inspected the wiring harness in the engine bay.
Yr 83 is in the years that had insulation failure.
THE Place to look first is the wires at the Grey Cnxn Block at the firewall near the Oil Dip Stick.

Check the wires on the engine side, if you see rotten insulation there, unwrap/slit the cover and follow them as they go under the intake manifold.