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Discussion Starter #42
What is that?
The bad ground wire I had located earlier. After narrowing it down, that section was the only ground gave me an ohm reading. When I tested that ground properly (took me awhile), I got 17.50Kohm, moved the wire slightly, got 350ohm.

So I figure I should repair that, and go forward from there.
 

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Voltage drop testing is more sensitive than looking at resistance if it's not a major break. This is from Rob Siegel who wrote a book on BMW electronics. The technique is otherwise the same. Start wide and then move in one connection at a time to pinpoint the bad one.
I would not argue that voltage drop does not have it's place, but it is not here. It is useful when you find everything appears normal. It is pointless when a wire that should have 0 Ohms resistance has a fluctuating resistance.
Suggesting it when you did was like letting him chase the bad guys into a room then suggesting he walk away go back to the office and start the investigation again.
It especially will not help in a case where a wire has been forgotten when a new ground bundle was created. Just a guess but I suspect that joint is not factory but made while working on the lights and the true ground was dropped somewhere.
 

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The bad ground wire I had located earlier. After narrowing it down, that section was the only ground gave me an ohm reading. When I tested that ground properly (took me awhile), I got 17.50Kohm, moved the wire slightly, got 350ohm.
You don't get your point across well, I have a hard time understanding what you are trying to say. How did you measure that resistance? Have you measured the resistance from that joint to ground?
I wish you had of taken the picture, the ground goes to the body not a light. Again your post was very unclear and I really have no idea what you saw. I am guessing, but this might be simpler than you think. I think you are simply missing a wire to ground and your lights were working as a ground for sometime then finally sad screw this it is not my job when a part burnt out.
 

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Discussion Starter #45 (Edited)
You don't get your point across well, I have a hard time understanding what you are trying to say. How did you measure that resistance? Have you measured the resistance from that joint to ground?
I wish you had of taken the picture, the ground goes to the body not a light. Again your post was very unclear and I really have no idea what you saw. I am guessing, but this might be simpler than you think. I think you are simply missing a wire to ground and your lights were working as a ground for sometime then finally sad screw this it is not my job when a part burnt out.

I measured from the relay ground to body, got 17.50kohm. I then measured from the splice to ground and got 0ohm. I measured from the fuel pump plug to ground (again properly this time) and got 0ohm. I went back to the relay and retested it to ground and got 350ohm. After I tested the splice to ground and got .2ohm.

Shouldn't that tell me the problem is between the relay and the splice? Which has a what looks to be damaged ground wire.
941132


The ground I used is located under the passenger light, to the body. Shown here.
941134
 

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The ground I used is located under the passenger light, to the body. Shown here.
You used that for what? I still am having a hard time understanding all, that you are trying to say, sorry.
Is that also where you followed the wire from the joint that should go to ground? I ask because the wire in that ground block(with the red arrow) is brown with a black stripe and the other wire on the single lug looks? It does not look like the other factory brown wires, and all the wires at the joint are factory brown? This is what I don't don't understand.
If you did the tests from that thread correctly the ground wire from the joint back to the relay plug would be of no concern, it would have just been sitting there. The test should have sent positive power through your jumper down the red/white wire, through the pump then into the ground at the plug. From there the power would travel to the joint and into the wire going to the ground block. It would not have tried to go up the wire from the joint to the relay block unless something was plugged into that. Nothing could have been plugged in because you were using that space as your jump. That crimp could be the issue but it does not look bad, but it still might be.
Is the pump in or out of the car?
 

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Discussion Starter #47 (Edited)
The fuel pump is out of the car at the moment. I used that picture to show you where I grounded as I didn't have one. That picture of the ground block is not my car, it was an example.

The tests I was able to do before I had to leave the car, were just basic resistance tests, properly. That splice has my fuel pump ground, fuel pump relay ground, and a ground wiring that leads to the block shown. All I did was test the resistance in those series of grounds, and found an issue at the relay ground wire. Fuel Pump Plug to body which was good, the crimp splice to body which was good and then relay to body, which wasn't good.

I haven't had a chance to run the tests in the thread you mentioned because I haven't been at the car.
 

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Discussion Starter #49
But you told me you did and said the pump would not run?
That block is not likely the correct ground as the wire colors are not right.
I didn't do it right. Because I didn't understand what I was doing, I'm understand this a little more now, so I will re retest and see.

I followed the ground from the splice, I can tell you with absolute certainty, that it goes to that block on my car. Remember...the picture of the ground block I showed you was just pulled from Google to explain what I was using as ground/body.
 

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Pulling a picture from the net does not really help because I want to see YOURS. Let me be clear about this. The tests I ask you to do is so I can understand what is going on. If you do the test different and don't do as I asked you make me think the wrong things and I can't figure out what is going on. The tests I give are exactly what I would do, and I would have no issues figuring this out. In fact in probably less than 1/2 an hour I would know exactly what was wrong.
 

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When I get home tonight I will type out a list of test and the order they should be done in. You will learn how to diagnose from this and may even start to understand what all the tests are for. I am not going to write an essay but I will try to include what I am looking for with each test.
 

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Discussion Starter #52
When I get home tonight I will type out a list of test and the order they should be done in. You will learn how to diagnose from this and may even start to understand what all the tests are for. I am not going to write an essay but I will try to include what I am looking for with each test.

That works for me...thank you for taking the time to do that. When I first started this, I knew nothing about car electrical, so this is a major learning experience for me, but I really don't want this to beat me.

I don't mean to confuse or mislead, I am trying my best given the situation. Thanks again.
 

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I don't mean to confuse or mislead, I am trying my best given the situation.
I get that. I have all this info and know how stored, I don't type it all out or would be typing for months on simple things. When you decide that some info you gave me was wrong or you are unsure you have to let me know. Diag is done like a tree, and you follow the tree by answering yes or no to specific things that rule things out. In this case that test in the linked thread is the most basic. It only has two answers yes the pump runs, or no the pump does not run. Depending on the answer you go right or left and because you said no it did not run I am all the way on the right hanging from my finger tips when maybe I should be all the way left sitting on a branch.
I will sit down in a bit and we can start again.
 

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I don't have time to do this all tonight, but I will give you the first test, and tell you what you are doing and why.
The first thing you have to do is put everything back together with the pump in place. Once you have everything in place try and start the car and hopefully it will not start, if it does it means that the fault is not present so you can't find a fault that is not present. You will have to wait for it to come back.
Assuming it will not start because the fault is present. Unplug the relay Test for 12V at pin 6 on the the relay plug not the relay. There should be 12V there even with the key out, but test with the key out and position 2. Pin 6 is the red purple wire, but read that other thread for more details, but do this test my way. If yes to 12v use a jumper and jump pin 6 to pin 2 the red white wire. Don't do more than that to avoid mistakes. If the pump does not run it tells us there is a fault somewhere in the pump circuit. There mi9ght be other faults but this is the first fault to address.
By jumping those pins we are splitting the system in half.
One have is the pump circuit and the other half is the activation circuit which includes DME, relay and all the wires connecting them.
So here is that tree if the pump does run we know to only look at the activation circuit because the pump runs if we give it power directly so simple logic says something that activates is not working if the whole system is used, so the activation circuit has a fault. This also rules out all the wires for the pump and the pump so we don't have to look at any of the parts that make that work. This means we know a ton of the shared wiring is good. The pump demands the most of the wires. One of the reasons we test it first.
If the pump does not run then we know there is a fault in the pump system so we will diag that. It does not mean there is not a second fault in the other circuit, but we don't care at this point all we want to do is have the pump run to rule out the other stuff.
If the pump does not run we slide over to that side of the tree and work on it. You have bench tested the pump and we know it runs so that only leaves the wires to test. Although you have tested them your tests would indicate the pump should run, if it is not running then something went wrong in your tests.
So revising what I have already said I will give you a new test. First test in this section is put the jumper back in the relay plug set your meter to DC V put the red probe on that ground joint and the black probe to ground, but not a ground of the system you are checking, IE that lug you used before. Neg on the battery would be your best choice.
If the meter reads 12V then that sort of tells us everything from the relay plug to that joint is good. Pull the jumper now hook up a new wire at that joint and take it to the battery neg terminal, plug the jumper back in, does the pump run?
That is it for now out of time. Except I should mention that place you were trying to do ground tests from. That block is part of the system you are testing depending on where you put the probe you could skip part of the circuit so when doing ground tests alway use the body or better the neg term on the batt.
If the
 

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Discussion Starter #55
Okay, so today I was able to get to the car. I have 11.8V at 6pin on the relay plug, battery voltage was 11.8V however, so I think that's irrelevant. I used my jumper to jump pin 2 and 6 and the pump did not run. I reinserted the jumper, and double check at the pump plug, it was getting 11.8V as well.

Now I want to clarify for the next step, you wanted me to put the jumper back into 2/6 and set my meter to DC V and stick the red probe into that splice, and the black to the negative terminal on the battery?

Because when I reinsert the jumper, and try to take a voltage reading from the joint/splice to ground, I get really weird readings 60m Volts, which doesn't make any sense to me. I did take a reading from the jumper wire (6/2 pins) to ground and I did get 11.8V. I also got 10.80V from jumper to joint. So does that point to a problem?
 

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Before I get to far down the rabbit hole just twist a wire around the joint and take it to the battery and put the jumper back in. If you did not get 12v at the joint it says something is wrong before the joint, but there is a small chance the pump is sitting in a funny spot between brushes. The fact you got 12 v from the jumper to the joint suggests that the joint to ground is good. At this point I would start puncturing wires, but I have the correct tools, but I don't want to tell you to do that. Let me think how someone without the right tools could do that. Did not take long I had not even finished typing that sentence. You could push a straight pin through the wire and touch your probe to that. I think it is still safer to just do Ohms readings.
I wish those plugs were not sealed and you could back probe them, but as I recall they are sealed tight to avoid sparks.
Since doing any part of a voltage drop test requires volts and that could be sparks, it also means piercing wires that is your choice, I am saying for safety sake avoid that.
So now you need to move back to OHMs tests but you could still do one more voltage test. Unplug the pump secure your probe to the red white wire on the wire side of the pump plug, meter set to volts, and the other probe secured to a ground. Then put the jumper wire in and read the voltage.
The odds on you having vapor leaks is low but I don't know you or if you would even be concerned if you smelled gas, maybe you have even left the tank open. I don't want to give you tests that might have risk.
Assuming you have 12 v at the plug, unhook all that, plug the pump back in and pierce the ground coming from the pump with a pin. measure ohms from the pin all the way back to the red white wire at the relay plug pin two.
Since you are right there and have your extension wire in hand measure the ohms from the inserted pin to the joint then move the probe at the joint to any ground and see if the reading is the same.
I would make sure things were safe and that inserted pin was in free air not touching anything, then I would set my meter to Volts hook the black to ground and the positive to the inserted pins. Then I would put the jumper in for a second or two. The thing is I have alligator clips and wire piercing probes for my meter and I also have hold feature which will read the max volts and not go to 0 when the power is off. You don't have those things so it is way more dangerous for you to do it.
If you took the time to tape the joints and clamp the probes in place, you could make it safe, but all that is up to you. You decide what the dangers are and how to work safe, I am saying do the ohms because it is safe, but someone else has said voltage drop test without any warnings so I am trying to cover the bases.
Just had an idea that is safe. Start at the spot when I said to push a pin through the ground wire, once it is in place twist a spare wire to it and connect the other end of that wire to a solid ground. Put the jumper back in and see if the pump runs. That seems might even be easier for a beginner.
What all that is going to do is say everything between the inserted pin and the red white wire at the relay plug is good then we can ignore it.
 

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Discussion Starter #57
Tonight I will run the new ground to the negative just to see, but I will buy a lead kit before piercing wires with needles, may as well have one handy. Once I have the probe lead kit I'll continue on that test route.
 

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You should also buy a test light of good quality. It should have a narrow sharp point for piercing wires and an alligator clip for the ground. While you are doing what you can measure the voltage twice at the plug for the pump on the wire side. The positive probe will be in the red white wire but test the neg in the plug then again straight to ground. The jumper wire must be in for both of those tests.
 

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Discussion Starter #60
You should also buy a test light of good quality.
I have a snap-on test light that I picked up a while ago during a promotion, I think it should suffice? Looking at power probe lead sets for the back probing leads which seems to be of decent quality.
 
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