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LTb1ow
08-04-2015, 01:30 PM
CS144 alternator, in a 95 LT1 car.

Can I take the DC voltage sensing lead and run it to the battery post? From everything I have come across this seems perfectly doable.
BonzoHansen
08-04-2015, 02:27 PM
does your battery cable go to a junction somewhere, like the fuse/relay box?

what problem are you having?
LTb1ow
08-04-2015, 02:32 PM
Alternator has a 1/0 wire to battery, battery has a 1/0 to starter stud, accessory relay panel has 1/0 to starter stud, alternator housing has 1/0 to chassis ground, battery ground has 1/0 to chassis ground.

Issue is, when hot, voltage seems to plummet and its been a bothersome issue for awhile. It seems the alternator cannot stabilize the voltage spikes so figured sticking POR at battery would help bump voltage out of alternator.
BonzoHansen
08-04-2015, 04:26 PM
is that how it was run factory? Specifically starter to replay/distribution block? Battery in trunk?

No engine to chassis ground?
LTb1ow
08-05-2015, 06:24 AM
Nothing close to factory anymore.

Battery in trunk, engine/alternator share a large 1/0 ground to chassis. Starting isn't an issue so I feel ground is fine engine to chassis.

When fans kick on voltage drop is horrendous and I wanna do what I can to fix it.

Basically
http://www.madelectrical.com/electricaltech/remotevoltagesensing.shtml

Would love to toss the POR at battery in trunk and have alternator run slightly more voltage
BonzoHansen
08-05-2015, 07:45 AM
is it only on fan start up or whenever they are running? two fans i assume, how many relays? do they have low & high speed settings? of so how is that wired?
LTb1ow
08-05-2015, 07:52 AM
Fans are not OEM wired with half voltage/three relay

Relay for each, PCM triggers high or low based on temps. IMO when fans and pumps are running, battery is discharging.
BonzoHansen
08-05-2015, 08:16 AM
ok so not just a spike. I'd have used the 3 relay setup but you probably have a reason you didn't go that way. either way that does not seem to be an issue here.
LTb1ow
08-05-2015, 08:43 AM
ok so not just a spike. I'd have used the 3 relay setup but you probably have a reason you didn't go that way. either way that does not seem to be an issue here.

Yea, I have been down this road, actually never got back from down it :lol:

I have done as much as I can think of to negate the issue and it persists. Down and dirty method would be to hook 1/0 from the relay board straight to alternator instead of battery. But this would not pass tech and allow for all electrical to run with cutoff switched off.

Other thing I can perhaps think of is internal voltage regulator is dead in alternator, but that is a guess based on heat/load combos.