Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   Porsche 911 Technical Forum (http://forums.pelicanparts.com/porsche-911-technical-forum/)
-   -   My alt warning light doesn't come on when turning the key. What's up (http://forums.pelicanparts.com/porsche-911-technical-forum/51933-my-alt-warning-light-doesnt-come-when-turning-key-whats-up.html)

chrisp 11-13-2001 05:18 AM

My alt warning light doesn't come on when turning the key. What's up
 
The alternator warning should come on (along with the oil pres warning light) whenever the ignition switch is turned to the on position when starting the car. Mine no longer does.

Any ideas on the problem? I haven't checked the volts to the battery but I suspect my alternator is fine as it was just replaced 4 months ago. I'll check that tonight. All fuses in the front luggage compart look good. Could it be a fuse somewhere else (everything else electrical works fine)?

Jdub 11-13-2001 05:49 AM

This is often discussed here; the Search mechanism can help in these situations.

For a nice writeup, see http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=51717

Jw

john walker's workshop 11-13-2001 07:07 AM

that's the exciter current that gets the alternator into the charging mode. if the brushes are worn down, the circuit can't ground and the light won't come on. possibly it's the bulb. put a voltmeter across the battery terms. when you start the engine, the voltage should increase. 13.8-14.2 is normal.

chrisp 11-13-2001 08:32 AM

I put a test light accross the connections to the back of the alt warning light. The test light doesn't light either....so it's not the battery.

I'll check the current as planned but if the current is okay then I have no idea what's up. That's why I am fearing. Without this warning light I am running a little blind and I am ignoring some other (potentially) bad condition.

chrisp 11-13-2001 08:32 AM

SOrry, I meant to say "bulb" in the first sentence...not "battery" Sorry.

john walker's workshop 11-13-2001 10:04 AM

the black/red wire is just "key on" power that also powers other bulbs, etc. your test light should work on that. the blue wire goes to the alt and regulator (if it's external), and grounds thru the alt circuit. it passes thru the 14 pin connector in the engine area, so check that for corrosion.

joehahn 11-13-2001 10:28 AM

...how about on a 1968 car John? Is it similar? Is the test similar?

john walker's workshop 11-13-2001 11:20 AM

same, except there's no 14 pin connector.


All times are GMT -8. The time now is 09:24 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.