dirtgar

My Z28 was dead so I decided to jump start the battery with jumper cables attached to my truck, I think I must of have messed something up or burned some sort of cable, because after I tried jumping the battery the car now burns the ignition fuse that’s located on the driver side engine compartment this happens every time I try turning the car on. I need to know what items I need to start checking. Also does the 97 z28 have fuses in the battery cables? Or some other sort of cable on the starter???

Injuneer

You Owner's Manual will tell you what systems are powered from each specific fuse. You have to check everything that's powered by the fuse, and the wires connecting to each of them. If you don't have an Owner's Manual, check the online copy, using Shoebox's link:

http://shbox.com/pdf/manuals.html

There are no fuses in the wires from the battery to the starter, or the grounds. There are fusible links attached to the red "+" box for some systems, like the fans. Shoebox's 96 battery/starter wiring diagram will show you how the wiring goes. 97 should be the same as 96.

http://shbox.com/1/starter_charging_96.jpg

Guest47904

Let's try to make this easy. If your referring to the number 11 fuse that is 10 AMP. It powers the ICM, CKP and the coil. To get power to those devices from the fuse, it has to travel through connector C100 then to a splice where it branches off to the 3 devices listed.

To find the problem you could do it several ways but here is what I recommend. With a good fuse in place, disconnect C100 (It's the black 10 pin connector) located near the PCM. Now try cranking the engine. If the fuse now blows, the problem is the wire between the fuse and connector C100 touching ground. The wire is pink.

If the fuse does NOT blow after that, plug the C100 connector back in then disconnect one of the 3 devices. Lets say the Coil. Now crank it over. IF the fuse is not blown, the problem is probably the coil

If it is blown, replace the fuse and disconnect the crank position sensor (CKP). Crank it and check the fuse. If it is not blown the problem is the CKP. If it is blown, disconnect the ICM. Replace the fuse and crank it over. If the fuse is NOT blown, the problem is the ICM. If it is now still blown, the problem is the wiring between the connector C100 and any of the 3 devices listed. At this point with all the devices and C100 disconnected, you will need to ohm the correct pink wire to ground. Then trudge through the entire length of the pink wire. It is the pink wire on pin G of C100. NOT the one on the end of C100 (A).

Never ohm a wire that has voltage on it. Don't waste your time ohming a wire that is connected to a device. It can give you a false reading to ground as it may have low resistance. ie a bulb filament, motor or solid state device.

dirtgar

Thank's Speedy G I will try that test soon as I get a chance! So basicaly it has to be the wireing or on of thosse three components that is making the fuse 11 burn so quickly. Once I test it I will post my response, thanks!

dirtgar

Each component passed the test and the fuse didn't burn. Later I tired cranking the engine and sure enought the fuse burned, Im almost positve that the pink wire that fuse#11 is connected to most be damaged. I noticed after pulling and checking the wire then cranking it would not burn then later it would burn. Im going to try getting a tester and test the pink wire. I will post an update afterwards!

dirtgar

So how would I check the pink wire for ohm? What tool would I need and what ohm number am I looking for??

Guest47904

Hold on there. Stop, think and then clarify what you said. You disconnected the devices and the fuse did NOT blow.

"I noticed after pulling and checking the wire then cranking it would not burn then later it would burn."

So were the devices plugged in later? What we are trying to get to is what device if any causes the fuse to blow. You unplug a device and crank it over, if the fuse now does NOT blow, that is the device that caused the problem. Check it one more time. Plug it in, put a fuse in, crank it over. See if it blows again. Unplug the device, new fuse in, crank it over. Now fuse does NOT blow. There is the device causing the problem.

Get it?

The key is one device at a time. You don't pull all 3 at once.
Don't buy anything until you clarify the above description.

dirtgar

UPDATE!
So I went back and did the testing that speedy recomended and I managed to realize that the coil was the item that keep burning my fuse, I took the coil in to AZ and they checked it and said that it was putting out 8 ohms when it's supposed to out only about 6. The funny thing is that I replaced the coil in my z28 about two weeks ago with a coil from AZ, go figure they sold me a coil that was faulty. One thing I did notice was that the brand was BWD and they replaced it with a Duralast, anyway at this point I havent had time to put eveything back together and test it, but I will keep my fingers crossed and wish me luck! I hope that the coil was the part that was burning the ignition fuse.

dirtgar

Back to square one! Placed the new coil in and tried to start it, then checked the fuse and sure enought it had burned.

Guest47904

I think you deviated from the plan and perhaps didn't realize it.

I think this is key to your problem.
You didn't answer the question. You said it blew the fuse later. If the devices were not connected and it blew, the wire is the problem.

There is an easy way to find the wire problem WITHOUT the fuse in place. But at this point, I'm not sure you can handle it.

You need an ohm meter and a friend or an ohm meter with a continuity buzzer if you don't have a friend to help.

dirtgar

Okay I have a OHM tester, what Im i looking for when I test the wireing??

Injuneer

Why don't you go back and test the system as Speedy suggested, disconnecting one of the loads at a time. When you disconnect an item, and the fuse doesn't blow, you have found your problem.

Speedy can get a bit confrontational in his replies, but in this case it APPEARS you did not follow his suggested procedure, and even after he asked you twice to clarify what you did do, you ignored him. I can understand his frustration.

Guest47904

Assuming the wire is the problem, unplug all the devices powered by the fuse in question.

Ohm meter without a buzzer will require 2 people. Set the ohm meter to DC voltage and remove the fuse that keeps blowing. Measure the contacts in the fuse panel for that fuse. One side will have 12 volts and the other side will not. The side that does NOT have 12 volts is the side you want to use.

Now set the meter to ohms. Put one of the meter leads on or in the fuse contacts that does not have 12 volts so it stays there. Put the other meter lead on a good ground point anywhere. If the meter reads low ohms, the wire is probably touching somewhere. You need to wiggle the entire length of the wire to find the point that makes it go to infinite (high) ohms.

If is reading high ohms when you connect it (just like it was showing with the leads not connected). You want to wiggle the entire length of the wire until it does read low ohms. When it does, that is where the short is likely.

Thanks I think. I did not realize I was being confrontational without being provoked? I guess is what he's saying. I will try to be less so in the future.

dirtgar

Sorry guys, Im not trying to ignore anyone, as it is I have recived so much help and insight! I really appreciate all your guys help

dirtgar

Okay guys please be patient with me, I have never used a multimeter before. What I understand so far is that I need to remove fuse 11, and use the connecters to test each connection, and that on one of those connections it should read 12V, but I’m not to use that one but the connection that has no voltage. Also while I’m doing this I need to make sure that the black multimeter connection is grounded. Next if the pink wire connection has high or infinite ohms then I need to wiggle the cable around in order to track the short. If it has low ohms then I also need to wiggle the cable around until it reads infinite ohms and that will be where the wire is shorted.