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> Charging light anomaly **UPDATE**
whiterabbit
post Mar 30 2021, 12:59 PM
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I've been browsing this site for awhile, as I restore my '75 914. I'm mostly done, just working on finishing touches and some drivability issues. You guys have been a huge help but the details of my current issue has me stumped. Below is a summary of the issue:

1-With key OUT of the ignition the charging light is "ON" (IMG:style_emoticons/default/WTF.gif)
2- Key in on position, the charging light turns "OFF", oil light turns "ON"
3- Engine Running, charging light is "OFF"
4- Engine running, voltage regulator plugged in, voltage at battery reads 12.4 volts (not charging).
5- Engine running, voltage regulator unplugged & jumper between D+/DF voltage at battery reads 12.6-12.8 volts (still not really charging).
6-Occasionally, ignition key needs to be cycled several times before the starter is triggered to start the car (probably unrelated?)
7-Charging light turns "OFF" when alternator plug (specifically DF connection) is disconnected from relay board.

Background info: New alternator 100 miles ago, belt tight, newer voltage regulator, new alternator wiring harness, newer ignition switch, transmission to trunk floor ground strap clean and tight. 20 miles ago, the charging system was working as it should.

My theory: Alternator failure! But I don't want to throw parts at the situation if there are other clues in points 1-7 above.
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whiterabbit
post Apr 6 2021, 09:35 AM
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Just an update on this charging light issue:

I replaced the alternator. Then I had a new set of symptoms.

1-With key OUT of the ignition the charging light is "OFF"
2- Key in on position, the charging light is "OFF", oil light turns "ON"
3- Engine Running, charging light is "OFF"
4- Engine running, voltage regulator plugged in, voltage at battery reads 12.4 volts (not charging).
5- Engine running, voltage regulator unplugged & jumper between D+/DF: voltage at battery reads 16.4 volts (battery is charging, VR failed??).

Replaced voltage regulator with spare and charging system is working as it should. So, it looks as though the alternator and voltage regulator both failed resulting in the symptoms of my original post.
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DRPHIL914
post Apr 6 2021, 10:24 AM
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QUOTE(whiterabbit @ Apr 6 2021, 11:35 AM) *

Just an update on this charging light issue:

I replaced the alternator. Then I had a new set of symptoms.

1-With key OUT of the ignition the charging light is "OFF"
2- Key in on position, the charging light is "OFF", oil light turns "ON"
3- Engine Running, charging light is "OFF"
4- Engine running, voltage regulator plugged in, voltage at battery reads 12.4 volts (not charging).
5- Engine running, voltage regulator unplugged & jumper between D+/DF: voltage at battery reads 16.4 volts (battery is charging, VR failed??).

Replaced voltage regulator with spare and charging system is working as it should. So, it looks as though the alternator and voltage regulator both failed resulting in the symptoms of my original post.

what are the chances of that happening? did one cause the other? i am always curious of the "why" not just what.
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