Had my kid hold it at 3000rpm
Hangs around 170-180 a lot but got a couple bumps up to 199amps
Hangs around 170-180 a lot but got a couple bumps up to 199amps
What did you do to your NNBS GMT900 Tahoe/Yukon Today?
- Thread starter phattyford
- Start date
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mattbta
Full Access Member
My Mechman 240a orange tag test results say 161a at 800 idle. I'm currently diagnosing with them, because on my NBS Tahoe at idle (525) with engine cooling fans on high and hvac blower on high, I drop down to low 12V at both alternator and battery. It did this with the stock 145a alt, so I got the upgraded one. Put on 1/0 charge cable and 4 different 1/0 grounds when installed. Doesn't matter if I have the 700w fans in or the 500w....tried both. Battery is new. I live in Texas, so no rust, but cleaned all grounds regardless. I need the HVAC at full due to said Texas. Even jumped the positive alt post to the alt turn on pin and still low 12's while talking with Richard @ Mechman.
Will get around to my own thread, just wanted to say i'm jealous. I should get an ammeter, too,
That last test was with everything on as well, front and rear ac on high, seat coolers, rear seat heaters, defroster, wipers, headlights, fogs, steering wheel heater, radio & amp, hazards, radar detector and dashcam. only thing I didn't have on was the rear wiper
thats wild.. any idea what's pulling 200 amps? that's seems massive.
my little car didn't budge when revved up. seems 100 was all it needed.
man I forget what my yukon inverter maxes out at on the 12v side, but I'm pretty it was less than 200amps haha. and that's with a 40amp electric tranny pump running off it. you definitely got some load there.
I'm guessing you've upgraded all the wiring?
mattbta
Full Access Member
20% off and same day delivery for Chinesium = $26. Thanks!
My Mechman 240a orange tag test results say 161a at 800 idle. I'm currently diagnosing with them, because on my NBS Tahoe at idle (525) with engine cooling fans on high and hvac blower on high, I drop down to low 12V at both alternator and battery. It did this with the stock 145a alt, so I got the upgraded one. Put on 1/0 charge cable and 4 different 1/0 grounds when installed. Doesn't matter if I have the 700w fans in or the 500w....tried both. Battery is new. I live in Texas, so no rust, but cleaned all grounds regardless. I need the HVAC at full due to said Texas. Even jumped the positive alt post to the alt turn on pin and still low 12's while talking with Richard @ Mechman.
Will get around to my own thread, just wanted to say i'm jealous. I should get an ammeter, too,
do you have the 2 wire pwm alternator too? or something else.
I'm just interested because you said they had to jump, I've not heard of that. I'm currently waiting on a part now that should put out the request the bcm normally sends to the ecm to start controlling voltage. (my car doesn't work that way) if there was a way to jump something it would save me the hassle.
if you have the 2 wire you could also try picking up the 100$ one iamdub got to try. they seem pretty good.
I have the 230a standard pulley it's been installed for about 3 years now I guess. I did upgrade the charging cable to 4 gauge (I think) had a shop make the cable for meMy Mechman 240a orange tag test results say 161a at 800 idle. I'm currently diagnosing with them, because on my NBS Tahoe at idle (525) with engine cooling fans on high and hvac blower on high, I drop down to low 12V at both alternator and battery. It did this with the stock 145a alt, so I got the upgraded one. Put on 1/0 charge cable and 4 different 1/0 grounds when installed. Doesn't matter if I have the 700w fans in or the 500w....tried both. Battery is new. I live in Texas, so no rust, but cleaned all grounds regardless. I need the HVAC at full due to said Texas. Even jumped the positive alt post to the alt turn on pin and still low 12's while talking with Richard @ Mechman.
Will get around to my own thread, just wanted to say i'm jealous. I should get an ammeter, too,
I have dual batterys in parallel and 2 extra 0 gauge grounds. both batterys go to the starter and I have both grounded together. everything works fine
I was fighting with the rvc previous to getting the mechman thought it was the alternator but turned out to be a bad battery it would show 12v but it's wasn't charging correctly and would cause the rvc to read incorrectly and not bump the voltage up
mattbta
Full Access Member
My 2004 NBS is a 4 pin (but only has three wires) and no RVC.
I see there are some two-to-four adapters. Wonder if there’s harm trying out an OEM 160 or 220 like you mention?
what does it do when you run just the 1 pin with 12v excite, running just the one pin will throw the light on the dash but alternator will be working
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