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-   -   help with electrical issues! (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/help-electrical-issues-617136/)

marcus219 Jan 24, 2007 11:30 AM

help with electrical issues!
 
hey guys. im having electrical issues. I'm gettin excessive voltage drop. Sunroof motor barely moves, when i turn on blow motor it drops voltage to like 8 volts and the resetable fuse trips (breaker). Also i put in new headlights like a week ago and the brights dont work on both headlights (not a coincidence im sure). anyways, alternator was tested at auto zone and they said it was good. I rebuilt it like 4 months ago with new brushes (old Voltage Reg. though) I also replaced the negative batt cable all the way to starter. I did a TII swap and as im sure some of you know you have to run new wires for the VR plug in the back of the alt. I sent to black white one key switched power and the white black i ran to the cpu unit. My alternator only puts out like 13.5 and i see like 12.9 at the battery. So maybe im dropping off voltage from wire out of alt. too battery? Any help appreciated.

s4 13BT, haltech e6k

mwalker Jan 24, 2007 12:03 PM

im having vaguely similar random electrical problems would be curious to know how to troubleshoot. i am pretty sure one of my ignition coils is shot, or both of them, but not positive and no real way to test. my car would start with the starter but the starter would take several tries and when it did start power flow would start at about 8 then boost to about 14 on the battery gauge after two accelerator revs. clock flashes 1:00 from start up every single time no matter what, and the seat belt light pulses. i'm replacing the plug cables but two of them were seriously corroded at the ignition coil end. i dont want to have to pay a gazillion dollars for two new ignition coils but the starter got killed by the problem after a month and that's under warrantee still. my radio won't work because of whatever is causing the seat belt light to pulse. at one point i noticed the back plug on the alternator fell out (wtf?) but putting it back in didn't change anything. any comments/ideas/suggestions/references to other posts would be appreciated.

Icemark Jan 25, 2007 05:03 PM

The alt only putting out 13.5 (just barely able to even charge the battery) is probably your problem.

For a properlly running system, you should have 14.4 volts.

fredster102 Jan 25, 2007 07:57 PM

i agree i got a alt from a scrapyard after i blew mine and its at 16 constantly on the dash guage

Icemark Jan 25, 2007 10:33 PM


Originally Posted by fredster102
i agree i got a alt from a scrapyard after i blew mine and its at 16 constantly on the dash guage

16 volts is way past the maximum and you will start burning up parts, like headlights and computers.

Again, the voltage should be 14.4 volts with the engine running.

Above 15 volts is very bad, and you should not drive the car until that is fixed.

Under 13.6 with the engine running volts is bad

Under 13.5 volts and the battery will not charge

Under 12.6 volts and the car is running on the battery, and the alt is not producing enough voltage to even run the car.

fcdin Jan 25, 2007 10:59 PM

yeah mines was running 16 when i got it too (about 1 week ago)..so i would turn everything on so it wouldnt be so high..but today for some reason i think my alternator died..no recharging happening..whys that?!

Icemark Jan 25, 2007 11:22 PM


Originally Posted by fcdin
yeah mines was running 16 when i got it too (about 1 week ago)..so i would turn everything on so it wouldnt be so high..but today for some reason i think my alternator died..no recharging happening..whys that?!

you could have boiled the battery

My5ABaby Jan 26, 2007 06:37 AM

I wouldn't trust the in-dash gauge either. Mine sits at anywhere between 11.8v and 13v. It's never been higher. However, I've never had a problem in the past 4+ months with it being like that. That includes several extended cranking periods.

marcus219 Jan 26, 2007 11:15 AM

i put a turbo drivetrain into my gxl. the plug in the back of the alt that goes to the voltage regulator, does it sound like i have that wired correctly? i ran the black white to key switched 12 volts and the white black to the cpu.


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