Ignition fuse keeps burning after I jumped the Batt
10-26-2010, 09:32 PM
#16
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Join Date: Sep 2004
Posts: 0
First understand the use of the ohm meter. When it is set to Ohms, notice the reading when the leads are not touching each other. That is infinite or OL. When the leads touch each other, that is as close to zero as it gets. This is because it is reading the resistance of the device you are measuring between the leads. There is nothing between the leads when they touch each other so there is no resistance other than the surface of the leads so say that reading is 0. Get it?
A pure resistance reading between leads does not care which lead is connected to what. So the black does not have to be connected to ground. That applies to voltage so don't let that trip you up.
You should do as Fred suggested and redo the test as I laid it out but you can do this test now and if you don't get the result we need to confirm the wire is touching ground, you can go back and do the other test again.
First any where along a wire is the same as any other point on a wire. In that, if one end is touching ground, you can measure any point on that wire to see if it is touching ground. Could be the other end. But finding the point that is touching ground is the problem. There are devices for that but we don't have them here. So we try to find them the only other way we can.
A fuse is a bridge of sorts from voltage to a device. On one side of this fuse is 12 volts, and on the other is the devices in question. So we don't want to test the side of the fuse with 12 volts. We want to test the side of the fuse connections that does NOT have 12 volts. Some where on this side of the fuse the pink wire may be touching ground. If we place one of the leads on the fuse contacts and the other lead on ground, we may be able to find it if it's there.
If you put one lead on the fuse contact that is not powered with 12 volts. The other on ground, there should be a very high resistance. As if the meter was not connected to anything. Remember when you had the leads apart and not touching each other when the meter was set to ohms?
That is the way the pink wire should be with the fuse out and all the devices I mentioned not connected. So be sure to unplug all the devices I listed.
Put one lead on the fuse contact that does NOT have 12 volts on it an the other lead to ground. If the meter reads low or high, you want to wiggle the entire length of the wire to see if it changes. If the resistance is high, like when the leads are not connected to each other, then that is good and what you want.
If the resistance is low, that is bad, indicating there is a short to ground.
So if the resistance goes low when you wiggle the wire or is low before you wiggle the wire, that is not good. Understand?
What you want is the resistance to be high and stay high no matter what you do. If it's high and goes low when you wiggle the wire or it is low and goes high when you wiggle the wire, that is bad and you have to find the bad spot.
So to restate what you want. When you measure the resistance of the wire to ground. It should be a high resistance (OL displayed on some digital meters) and stay that way no matter how much you wiggle, poke or prod. Remember, the devices plugged into the wire must be removed to run this test. Use the side of the fuse connections that is NOT powered up by 12 volts and the fuse must be OUT.
A pure resistance reading between leads does not care which lead is connected to what. So the black does not have to be connected to ground. That applies to voltage so don't let that trip you up.
You should do as Fred suggested and redo the test as I laid it out but you can do this test now and if you don't get the result we need to confirm the wire is touching ground, you can go back and do the other test again.
First any where along a wire is the same as any other point on a wire. In that, if one end is touching ground, you can measure any point on that wire to see if it is touching ground. Could be the other end. But finding the point that is touching ground is the problem. There are devices for that but we don't have them here. So we try to find them the only other way we can.
A fuse is a bridge of sorts from voltage to a device. On one side of this fuse is 12 volts, and on the other is the devices in question. So we don't want to test the side of the fuse with 12 volts. We want to test the side of the fuse connections that does NOT have 12 volts. Some where on this side of the fuse the pink wire may be touching ground. If we place one of the leads on the fuse contacts and the other lead on ground, we may be able to find it if it's there.
If you put one lead on the fuse contact that is not powered with 12 volts. The other on ground, there should be a very high resistance. As if the meter was not connected to anything. Remember when you had the leads apart and not touching each other when the meter was set to ohms?
That is the way the pink wire should be with the fuse out and all the devices I mentioned not connected. So be sure to unplug all the devices I listed.
Put one lead on the fuse contact that does NOT have 12 volts on it an the other lead to ground. If the meter reads low or high, you want to wiggle the entire length of the wire to see if it changes. If the resistance is high, like when the leads are not connected to each other, then that is good and what you want.
If the resistance is low, that is bad, indicating there is a short to ground.
So if the resistance goes low when you wiggle the wire or is low before you wiggle the wire, that is not good. Understand?
What you want is the resistance to be high and stay high no matter what you do. If it's high and goes low when you wiggle the wire or it is low and goes high when you wiggle the wire, that is bad and you have to find the bad spot.
So to restate what you want. When you measure the resistance of the wire to ground. It should be a high resistance (OL displayed on some digital meters) and stay that way no matter how much you wiggle, poke or prod. Remember, the devices plugged into the wire must be removed to run this test. Use the side of the fuse connections that is NOT powered up by 12 volts and the fuse must be OUT.
Last edited by Guest47904; 10-27-2010 at 05:31 AM.
10-28-2010, 08:39 PM
#17
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Thread Starter
Join Date: Sep 2010
Location: Cheyenne, WY
Posts: 117
SPEEDY THANKS!
The pink wire that powers the ICM, Coil and fuse was pulled and it had been streched far enought that it was damaged from the inside. I cut the wire and soldered the other side and good to go!
Now to the next issue
the car wants to start but it keeps backfiring really bad?? I have just replaced the opti, but I will open a new post for that issue, thanks everyone
The pink wire that powers the ICM, Coil and fuse was pulled and it had been streched far enought that it was damaged from the inside. I cut the wire and soldered the other side and good to go!
Now to the next issue
the car wants to start but it keeps backfiring really bad?? I have just replaced the opti, but I will open a new post for that issue, thanks everyone
10-29-2010, 01:00 PM
#19
Registered User
Thread Starter
Join Date: Sep 2010
Location: Cheyenne, WY
Posts: 117
Seriously whats your problem?
Yeah all three problems are related because it's the same car!
I've had all thosse issues and know that thosse issues are solved, I think the new opti spark in the car is making it backfire when I crank the engine. Im not lying this is what it is no need for anyone to get angry, I love this forum but man some people need to chill out. Once again thanks for all your guys help
Yeah all three problems are related because it's the same car!
I've had all thosse issues and know that thosse issues are solved, I think the new opti spark in the car is making it backfire when I crank the engine. Im not lying this is what it is no need for anyone to get angry, I love this forum but man some people need to chill out. Once again thanks for all your guys help
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