Positive from Battery Shorted to Chassis - No Power to Anything?

[thefro526]

I was attempting to diagonose my electric fan set up today and let the positive lead I was working with touch the chassis. (Worth Noting that the Car is an 89 S13.)

There was a small spark and I heard a click as if a relay were triggered. The cable was grounded for no longer than a second, it was more of a tap than anything.

I continued on with my diag for a bit before I realized that what had power before no longer had power. Went to check to see if there was anything on in the cabin and there was nothing. My usual 'idiot check' of looking at the clock didn't work as it was off. (I check this because no matter what, if the car has power the clock should read a time.)

Thus far I've checked the following - both visually and by using a multimeter.

-75A Alternator Fusible Link
- (3) 30A Fusible Links Located in the Passenger Side Relay Box.
- (2) 25A Fusible Links Located in the Passenger Side Relay Box.
- (2) 15A Fuses Located in the Passenger Side Relay Box.
- (4) 10A Fuses Located in the Passenger Side Relay Box.
- Ground from Chassis to Battery (If removed, will spark slightly when reinstalled - something has to be getting power?)
- Battery Voltage
- Every Fuse in the right hand side of the Driver's Side Interior Fusebox
- The bottom 4 Fuses on the left hand side of the Driver's Side Interior Fusebox (Didn't bother with the top half as these are non-critical functions)
- Grounds in the radiator support (one on each side)

Does anyone have any idea of what's going on? Is there a certain relay that I cooked by shorting the battery? Does the car have some sort of hidden circuit breaker for instances like this?

1st Edit:
- Hooked up Load Tester to Battery, everything came back good - ruled out the battery being dead.
-One of the connectors for the accessory relay appeared to be burnt, will be testing the relay shortly.

2nd Edit:
-Found out that I was derping with the test light....
-Swapped the ACC relay with the one adjacent to it, nothing changed.

3rd Edit:
-Removed every fuse in the car again, including those I had checked before. They all were in working order.
-Starting to think that there's a 90% chance that I fried a relay, I'm going to sleep on the issue and then get to testing relays tomorrow. Please don't hesitate to offer advice, there's got to be something I'm missing here.

Will continue updating this with further data. If you haven't already noticed, my knowledge of DC electrical systems is very basic....

[edmorl]

sounds like I have the same problem :O

[fullthrottle]

Its a main fuse in your fuse.box under the hood. Its popped.

Sent from my SGH-T769 using Tapatalk 2

[thefro526]

Originally Posted by fullthrottle

Its a main fuse in your fuse.box under the hood. Its popped.

Sent from my SGH-T769 using Tapatalk 2

Which Fuse is that?

I've checked all of the fuses in my fuse box including the 4 10A, 2 15A, 3 30A fusible links, 2 25A Fusible Links and the 75A Fusible Link. All tested positive for conductivity.

[KiLLeR2001]

Replace the 75A, or temporarily bypass it by jumping a wire across just to see if you get power.

[thefro526]

Originally Posted by KiLLeR2001

Replace the 75A, or temporarily bypass it by jumping a wire across just to see if you get power.

Just jumped it with a piece of 10Ga wire and nothing happened.

I also tested the 75A Link with the meter again, Conductivity was fine (enough for the meter to beep) and resistance measured .5ohm.

[KiLLeR2001]

So with the battery plugged in. Take the 75A fuse out, probe the side towards the battery with the positive lead, and negative lead to the chassis.

If 12V does not exist than the problem is from the battery terminal up to that spot. If 12V does exist then the problem is after the fusebox.

[thefro526]

Originally Posted by KiLLeR2001

So with the battery plugged in. Take the 75A fuse out, probe the side towards the battery with the positive lead, and negative lead to the chassis.

If 12V does not exist than the problem is from the battery terminal up to that spot. If 12V does exist then the problem is after the fusebox.

Interestingly enough, I did exactly this. The prong on the left hand side (when standing at the front of the car) has a connection to the hot (positive) side of the battery.

Am I under the correct assumption that all power in the car, excluding the starter go through the 75A Fusible Link?

I have checked most (though not all) of my grounds as well. All of them have continuity with the battery.

By process of elimination, I've ruled out any of the Fuses or Fusible links being the problem, as well as grounding and or power wires. This leaves me to believe that I must have fried a relay somewhere, I'm just not sure which relay would fit the symptoms that I'm experiencing.

The ACC relay in front of the driver's side wheel well did show some discoloration in the plastic connector which looked almost like it had been over heated and burnt. Does this Relay handle most/a significant portion of the chassis wiring?

(FWIW, I'm trying to add as much detail to each post as possible with the hope that it will make finding a solution easier and should someone have the same issue in the future they find this thread resourceful)

[KiLLeR2001]

Check the SMJ (super multiple junction). It is the huge plug on the driver side, above the fuse panel on the inside of the car, there are a couple relays there. I'm pretty sure they are related to power going into the vehicle. Check the FSM for verification.

[thefro526]

Originally Posted by KiLLeR2001

Check the SMJ (super multiple junction). It is the huge plug on the driver side, above the fuse panel on the inside of the car, there are a couple relays there. I'm pretty sure they are related to power going into the vehicle. Check the FSM for verification.

I'll write that on the list of things to check tomorrow morning. Gotta love the name 'super multiple junction.'

Thanks for all your help Killer.

[codyace]

Take ground wire off battery. Put test light between battery, and the negative lead. If there is a major draw, the light will 'light up'. Pull fuses and relays until it goes out. When it goes out, you now know the circuit to look into, and to diagnose.

[S14DB]

What was the positive lead connected to?

[thefro526]

Originally Posted by S14DB

What was the positive lead connected to?

The positive lead was connected to the positive terminal of the battery. I was using it to apply power directly to my fans when it shorted to the chassis.

I've checked the ACC relay under the hood, it's getting 12V power at the trigger pins and I was able to manually trigger the relay using an Auxiliary 12V source. I believe it's safe to assume that this is not the source of my problems.

I moved to the inside and checked a handful of fuses for power, and still nothing.

Once I get my hands on a test light, I'll start working on Cody's suggestion - though we did the same thing yesterday and the only thing sucking power was the interior lighting circuit and this went away once the door and trunk were closed.

Never been so stumped in my life.

[S14DB]

Have you tested the battery?

[thefro526]

Originally Posted by S14DB

Have you tested the battery?

Yes, it was load tested yesterday after all of this started.

[thefro526]

So, I'm an idiot.

I went back at this with a clear head when I got home from work. Took out the test light and did what Cody had suggest and got nothing.

Went through the fuse box again, both interior and exterior to see what actually was getting power and what wasn't. Found out that most everything seemed to have power that was supposed to, excluding some of the stuff on the ignition circuit.

I start probing around with the test light some more trying to trace wires and power when I notice the clock turned on and had been on for 3 minutes. Retraced the last few things I did, and then got back to poking the test light into the chassis.

Test light doesn't light up but the clock magically gets power again, but at first load (other than the clock) the power dies again...

Okay, cool, I have a problem between the negative terminal and the ground. Test the ground wire, no resistance on the meter, no problems with continuity so I'm stumped. I finally gave up, made two new ground cables and put them on the car. Everything works. Who knew.

Anywho, here's to hoping some poor soul has the same problems that I had and finds this thread while searching and finds it helpful.

Thanks again to everyone who offered advice.

[Danger_Dorn]

Thanks I'm getting zero power anywhere and keep frying my FL fuse. Ill try grounding galore.