Having some electrical issues. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

s14reaper · 09-01-2013, 09:58 PM

Hey guys, I did do a search and havent been able to come up with a solution. Anyways, so when I start the engine, it fires right up and runs well, but when I disconnect the negative battery cable to check the alternator the engine dies. So that lead me to believe I had a bad alternator, so I took it out and had it tested at a local parts store, passed with flying colors. So now I am thinking it is my wiring harness, could it be anything else? Oh and I checked all of my fuses too.

milto0n · 09-01-2013, 10:20 PM

I had the same problem not long ago. Check to make sure the black ground wire going from the alternator to the strut tower has continuity. Also, and more importantly, check to see that the alternator power wire has a black washer looking thing between it and the alternator. This was the issue I encountered. That power wire should not be making direct contact to the alternator, only the post it sits on.

milto0n · 09-01-2013, 10:21 PM

Also, wrong section.

lflkajfj12123 · 09-01-2013, 10:26 PM

make sure the 7.5 meter gauge fuse in the cabin is good

the voltage regulator wires into it

i had the same issue and my idiot lights weren't coming on

i also thought i had looked over the fuses already

use a multimeter to check the alternator also

you should be getting 13.7+ volts from battery if the alternator is operating correctly

dbeiler · 09-02-2013, 03:29 AM

The alternator output voltage must be checked AFTER the alternator has warmed up for several minutes. Check your alternator belt; make sure it's tight. A worn or loose belt will slip and the alternator won't be spinning fast enough. You don't have any electronics drawing excessive power? Subwoofer, amps, etc?

s14reaper · 09-02-2013, 03:37 PM

no i dont have any alternate electronic, everything is oem, i did what you guys suggested still nothing.

09-01-2013, 09:58 PM	#1
s14reaper Zilvia Member Join Date: Oct 2011 Location: Montebello Posts: 204 Trader Rating: (1) Feedback Score: 1 reviews	Having some electrical issues. Hey guys, I did do a search and havent been able to come up with a solution. Anyways, so when I start the engine, it fires right up and runs well, but when I disconnect the negative battery cable to check the alternator the engine dies. So that lead me to believe I had a bad alternator, so I took it out and had it tested at a local parts store, passed with flying colors. So now I am thinking it is my wiring harness, could it be anything else? Oh and I checked all of my fuses too.

09-01-2013, 10:20 PM	#2
milto0n Zilvia Junkie Join Date: Jun 2011 Location: Mesa, AZ Posts: 422 Trader Rating: (3) Feedback Score: 3 reviews	I had the same problem not long ago. Check to make sure the black ground wire going from the alternator to the strut tower has continuity. Also, and more importantly, check to see that the alternator power wire has a black washer looking thing between it and the alternator. This was the issue I encountered. That power wire should not be making direct contact to the alternator, only the post it sits on.

09-01-2013, 10:21 PM	#3
milto0n Zilvia Junkie Join Date: Jun 2011 Location: Mesa, AZ Posts: 422 Trader Rating: (3) Feedback Score: 3 reviews	Also, wrong section.

09-01-2013, 10:26 PM	#4
lflkajfj12123 Join Date: Apr 2007 Location: 　　　　　　　　 Posts: 8,483 Trader Rating: (20) Feedback Score: 20 reviews	make sure the 7.5 meter gauge fuse in the cabin is good the voltage regulator wires into it i had the same issue and my idiot lights weren't coming on i also thought i had looked over the fuses already use a multimeter to check the alternator also you should be getting 13.7+ volts from battery if the alternator is operating correctly

09-02-2013, 03:29 AM	#5
dbeiler Zilvia Junkie Join Date: Jun 2012 Location: Lancaster county, PA Age: 33 Posts: 465 Trader Rating: (4) Feedback Score: 4 reviews	The alternator output voltage must be checked AFTER the alternator has warmed up for several minutes. Check your alternator belt; make sure it's tight. A worn or loose belt will slip and the alternator won't be spinning fast enough. You don't have any electronics drawing excessive power? Subwoofer, amps, etc?

09-02-2013, 03:37 PM	#6
s14reaper Zilvia Member Join Date: Oct 2011 Location: Montebello Posts: 204 Trader Rating: (1) Feedback Score: 1 reviews	no i dont have any alternate electronic, everything is oem, i did what you guys suggested still nothing.