alternator not excited
Thread Starter
Racer
Joined: Jun 2006
Posts: 476
Likes: 0
From: Easton PA
alternator not excited
alternator not working checked for voltage on brown wire out at alternator (circuit 25) while engine running, nothing. this happened to me before then mysteriously starting working again but now not so much. anybody run into this issue with the brown exciter wire 0 voltage? alternator resently gone though, and cluster printed circuit board replaced. but this happened to me before these replacements, any guesses?
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
alternator not working checked for voltage on brown wire out at alternator (circuit 25) while engine running, nothing. this happened to me before then mysteriously starting working again but now not so much. anybody run into this issue with the brown exciter wire 0 voltage? alternator resently gone though, and cluster printed circuit board replaced. but this happened to me before these replacements, any guesses?
Alternately you can just jumper it over to the larger pos term on the back of the alternator or chase it down in the harness. It usually doesn't run too far depending on year.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
That little brown wire can break internally right at the connector and look fine but no current path. Back up into the harness 6 inches and check again.
I missed what year- some of the later (80-81-81?) had an electric heated choke. If the choke heater relay or fuse is inop the alternator won't charge- no juice to the brown wire.
Thread Starter
Racer
Joined: Jun 2006
Posts: 476
Likes: 0
From: Easton PA
alternator just rebuilt, but wont count out, wire diagram for '79 says brn wire goes from alternator basically rite to printed circuit board, guess will check continiuty, diagram for '80 shows a choke heater relay involved interesting. and im guess the 'gauges' fuse is involved with the brn wire (ckt 25) but cant tell for sure these factory diagrams suck. o ya alt. lite not on.
Burning Brakes
Joined: Jan 2006
Posts: 1,152
Likes: 23
From: Kawartha Lakes and PEC, Ontario
That little brown wire can break internally right at the connector and look fine but no current path. Back up into the harness 6 inches and check again.
I missed what year- some of the later (80-81-81?) had an electric heated choke. If the choke heater relay or fuse is inop the alternator won't charge- no juice to the brown wire.
Happened to me this summer.
Thread Starter
Racer
Joined: Jun 2006
Posts: 476
Likes: 0
From: Easton PA
update. checked for continuity between brown wire out at under hood and back at harness were it goes to printed circuit board, tested good. so then put the original alternator on and wham charging. so wondering what the heck and realized im using a cs130 alternator with pigtail adapter, checked adapter and no continuity from end to end. found a resister looks like in middle of wire that went so im going to change that resister and see whats up
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