Where is the alternator diode on an '83?

[djpateman]

diodes are inside the alternator

[chrisp]

that was why we switched the alt to stop the run on problem and the alt light problem.

anyone know if there's something similar or another diode outside the alternator that can be checked out?

[chrisp]

this is odd, where's my original post? it was there when i first posted this, now it's gone and your response is the first post.

[OSI930]

There is an alternator warning light diode located right behind the alternator warning light on an '83 SC. Look up part # 911 617 108 00 M100 from our host here as it shows a photo of what it looks like. Just pop out the gauge that contains the alternator warning light and you should see it. Check for current flow through the diode and go from there. I had a turbo that would not shut off with the key but all the accessories like the tach would shut off. That was the problem.

[chrisp]

thanks. my tach jumps around when i turn the key off.

i'll check it out!!

[chrisp]

Can i install a jumper wire and see if the car shuts down and/or the alt warning light works again? or will that fry the system?

[OSI930]

It is had to tell from your pictures but is there really a diode in that connector? The diode I bought from our host ( 911 617 108 00 M100) was much longer and you could see the diode in between the connectors. That looks like a simple connector in your photos.

[chrisp]

Not sure, I've never seen a diode. I agree that it doesn't look like the thing you directed me to on the PP site.

It's an odd looking connector though. I'll have to look again but I think both ends are sealed and it's not a connect/disconnect sort of thing.

The black discoloring of the end with the heat shrink tubing isn't a good sign.

[djpateman]

I could not understand what happened to your post either, but decided to reply as best I could.
It looks like the connector in your photo is similar to the part number mentioned. The parts inside your connector appear to be longer than just a simple disconnect. With diodes, you have to be sure you get the part installed properly (polarity is important). I'm more familiar with the diodes inside the alternator than this application. I'll have to view the schematic to see how they are using it, something new to learn.

[jmohn]

I thought the later SC's, with the internal voltage regulator, used a resistor in parallel with the warning light - not a diode. Or was the resistor only used when replacing an externally regulated alternator with an internally regulated?

Jerry M
'78 SC

[chrisp]

OSI930,

In looking at the picture of the part number you posted, I'm not sure how it connects to the wiring system. Did you splice it into existing wires or did the old one unplug and the new one replaces it?

[OSI930]

chrisp,

It has a male spade connector on each end. I am not sure if a turbo is wired different than an SC in this area but I don't think it is. Maybe someone on the board with an SC can verify.