Huge electrical problem with r32 gts4

[TheOrangeSkittle]

Okay so im not very good at electrical stuff with cars and ive searched for a solution on the web but have gotten no clear answer.    I was driving to work on the highway and everything is normal and suddenly I hear a loud pop and the dashlights get very bright then back to normal (this is at night by the way) and the background noise from the stock amp gets louder and sounds more erratic but the speakers and everything still works fine, then the hicas light starts flashing on and off every minute or so. Nothing else happens I park at work and shut it off, get back out to the car after and its totally dead nothing works.  I jump it and it starts no problem and the hicas immediately starts flashing faster and faster and I can hear some motor in the back turning off and on in sync with hicas light, and the power steering also stops working everytime.  it does this till I turn the car off hoping that the hicas turning on and off didnt damage anything.  Car is now dead again. Jumped once more and it runs rough for about a minute before stalling. I think maybe the amp blew and its drawing power or malfunctioning somehow when it shouldnt be so I cant figure out how to unplug it so I pull the amps fuse and jump it and it starts but not a single light in the interior will turn on in the dash or anything except headlights and I can give it some gas but i hear the hicas going wild in the back still, car stalls so I unplug hicas ecu and jump the car again and the lights are on and the hicas has stopped and no hicas light. Car still stalls after a few minutes. I jump it and let it charge for a few minutes then try and gun it home with high rpms and everything is working fine till suddenly 10minutes later a loud pop and dash lights flash bright then back to normal and the car starts slowing everything else working normally till I come to a stop then it all shuts off at once.  So have had it towed home and checked the battery with a multimeter and it reads 11.55v off and on and with the car revving it drops to like 11.40v  The loud pop sounded like it came from speakers and happend in sync with dash lights messing up. Anyone that knows anything about this cars electrical would be a massive help in diagnosing this.   Its a 1991 r32 skyline gts4. I suspect could be bad alternator or amp is drawing too much power now or hicas is being weird or bad battery.   Id say alternator right away but idk why the hicas and speakers would go wild together after they popped if it was the case. This pop happens even with the speakers off btw. 

 

Also forgot to add the tach doesnt work or any gauges besides fuel gauge when the dash lights go out. Which currently they are out and no electronics in car work except headlights but it will start and run under its own power with a quick charge.  Not sure if its still stalling havent tested that yet. 

 

 

 

 

Almost forgot to add sometimes the electronics and dash start working again and stay on if i rev the car to about 4or5k rpms and then let it idle they will be on till the car stalls again

Edited September 7, 2019 by TheOrangeSkittle

[White GTS-T]

Sounds like your alternator is stuffed. The regulator in your alternator is overcharging >16v (dash lights getting brighter ) and undercharging <12V causing all your electronics to play up. By disconnecting the amp and the Hicas ecu,  you're effectively lowering the load (electrical output) on the alternator.   You probably blew a few fuses in the meantime. I'd be getting the battery tested and your wiring (to the amp) checked. The noise coming from the amp sounds like electrical inteference. It is stalling because the alternator can't keep up the voltage supply after you jump start it. You'll need a new alternator, or have an autoelec rebuild it. Best to fit a new battery while your at it. And check all your fuses and fusable links. Good luck.

[TheOrangeSkittle]

Hello and thank you its what I thought it was too just never had this many weird problems with an alternator going bad.  Also the lights on the dash and the tachs dont work currently but occasionaly they will flicker when starting the car but not stay on. Could this be a fuse problem or would simply replacing the alternator fix this. Also the car is driveable just no turn signal or interior lights or anything. basically the only thing working is engine essentials and the headlights. 

[GTSBoy]

Almost all of the electical systems in your car at at risk of death from the voltage regulator failing. The HICAS CU is probably burnt. Who knows what else is already damaged. Stop using it. Get it to an auto electrician. That means tow it.

[Rusty Nuts]

1 hour ago, GTSBoy said:

Almost all of the electical systems in your car at at risk of death from the voltage regulator failing

Yes to all, My three series BMW did exactly what you described some time ago and it was the voltage regulator, but It fried the battery, the TCU and the ABS computer, So straight to the auto electrician is best advice and get the entire system checked.

[TheOrangeSkittle]

yes I had it towed back home and charged the battery, the hicas should be okay since I disconnected it the first time it was acting up when I charged the car and pushed it into the garage I started it one last time to see if the lights work and they all flickered on and stayed on so I just shut it off and am gunna wait till I can get it to someone to replace the alternator, I know a mechanic like 5 houses down who may be willing to do it and theres a more high end garage abit further that im sure can deal with it. The time I did use it was mainly test driving it around the parking lot for a minute and a short 5min attempt on the highway, everything on it seems to work properly still so Ill do like you all said and leave it for a pro thank you all for the help!.

[TheOrangeSkittle]

Hello so update on all of this im pretty sure my problem has been fixed. Took it to a guy familiar with skylines and he found the alternator did indeed crap itself and found charring on the internals along with a faulty connector and a bad fusible link that he discovered had already seperated but previous owner soldered it back together probably because he couldnt find another to replace it.  And it also had a bad battery so new fusible link plus re pinning the connectors with a new alternator and new battery seems to have fixed all issues. The car seems to even run smoother now than when I first got it. Thanks for any suggestions you guys gave!.

[GTSBoy]

That's good. Count your blessings that you didn't fry some shit!