Pelican Parts Forums - Strange Alternator light issue

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Quote:

Originally Posted by keynsham1 (Post 9001105)

Thanks timmy2, massively helpful for me!

:)
Happy to help. Hoping your next post will be all about how it works great now...

Don't do the upgrade-- you will need a different fan housing or have to machine your existing one, and the internally regulated alternator is a weak design that is prone to failure. The electrical components are 2" off the hot engine, with significant vibration. It's better to stick with an external reg over on the firewall.

Please post photos of all your components- your VR, your current alternator, and the associated wiring.

You can't full-field the alternator by connecting D+ to DF with the VR unplugged. D+ is the output from the trio diodes. And it's dangerous to connect +12v to DF, while this will send the field to maximum, it can also fry things.

The problem is in your wiring and it requires a meticulous approach to trace it out, but once you do it, you will solve the problem, and you will understand how the system works for future troubleshooting.

Well I have done the upgrade. I now have an alternator with an internal regulator and everything works perfectly. At last the warning light is out. Just for reference, all you need to do to fit the later alternator is trim the plastic cover behind to give a little clearance, unplug the external voltage regulator, and file out the centre of the clamp washer that sits behind the shaft nut as the new alternator has a 17mm thread and not 16mm as the original one was. There is no machining required of any other part. The new alternator is actually the same but with a regulator bolted on. As for the overheating and vibration issues mentioned, porsche recommend this modification and changed their own design accordingly. It can't be that bad or there would be major problems with the later cars.

My real problem was that the original alternator was mended and tested twice by a shop who did not know how to do it, and messed it up twice. I am now a little out of pocket but a lot wiser and more knowledgeable regarding charging circuits!

That is the happy post we all enjoy reading.
Now go out and have some fun driving it. :)