2006 X5 3.0i keeps running with key off

[andrewwynn]

The quick summary is to meaaure across the parts that are grounded for voltage. For example: measure from engine block to the negative jump terminal on the left fender. Then start the car. Should be a fraction of a volt like 0.4v.

[Siggy]

Originally Posted by andrewwynn

The quick summary is to meaaure across the parts that are grounded for voltage. For example: measure from engine block to the negative jump terminal on the left fender. Then start the car. Should be a fraction of a volt like 0.4v.

Thanks, I'll check that. I tried searching for the step by step but I didn't have much luck. Looked through a lot of results but couldn't find that step by step. Maybe I missed it.

I'll try what you posted above and see what that result is. What I'm confused about is when the car is running and I take the key out and unplug the switch and measure voltage on the pins, how's it getting 10V to all those wires because they aren't connected and don't share the same source plug. One wire goes to the immobilizer, one back to a plug in the fuse box. How's it got the same voltage on 2 wires that don't share a power source? I don't understand what's happening here.

[richardb]

curious to see how this turns out; did OP replace ignition switch yet?

[Siggy]

Originally Posted by richardb

curious to see how this turns out; did OP replace ignition switch yet?

On the 3rd or 4th one and 2nd or 3rd battery, all within 18 months or so.

[Clavurion]

If you are removing fuses to test this, I would start with the ones on Terminal R and Terminal 15 because you measured that those rails have power even when ignition switch is removed. So the base assumption is that something is tripping voltage to those rails when they should only be powered via ignition switch.

Here is what I summed from diagrams:

Terminal R

F7-9
F36-39
F41-42
F44-45

Terminal 15

F1-2
F4-6
F29
F31-34

Terminal 30

F3
F10-F28
F40
F46-50
F52-64

[Siggy]

Originally Posted by Clavurion

If you are removing fuses to test this, I would start with the ones on Terminal R and Terminal 15 because you measured that those rails have power even when ignition switch is removed. So the base assumption is that something is tripping voltage to those rails when they should only be powered via ignition switch.

Here is what I summed from diagrams:

Terminal R

F7-9
F36-39
F41-42
F44-45

Terminal 15

F1-2
F4-6
F29
F31-34

Terminal 30

F3
F10-F28
F40
F46-50
F52-64

Thanks, I'll get on that as soon as I can get a few minutes with it later today.

[Siggy]

I can't say for certain because the conditions I was working in weren't the best, but I don't get any voltage from the negative jump point and the engine. I'm not positive I had a good contact on the block as my hand was out of sight, under the manifold area. I'm reasonably confident it was on the block but I'm not positive. I checked a few other metal pieces (head, metal brackets I know bolt to the block), and I get nothing, just some mV readings on that.

I also started it, turned the key off and took it out, the car kept running, I left the ignition switch plugged in and started unplugging fuses, starting at the top of the list above.

None of them on Terminal R changed anything.

On Terminal 15, 1-2, 4-6 changed nothing. While searching for F29, the engine cut off, but the radio and everything else stayed on. Nothing else changed on any of those, F29, F31-34.

On Terminal 30, nothing changed, but I think one of them between 46-50 made the alarm go off but everything else stayed on. I could be wrong on that number, I was trying to work fast and didn't make note of the number that caused that.

Looks to me like none of them listed above help, but it also looks like there's no ground if I'm doing this right. I need to get a jack here (it's at my work) and get under it so I can track down that ground strap under the car, I suppose?

Or is there somewhere else I need to start with checking that?

[Clavurion]

What still puzzles me the most is your statement that those supply lines (pins 5, 6 and 7) drop voltage when this happens. So I would still verify that those pins have battery voltage in normal situation and if they drop voltage when the problem occurs, what's the voltage especially on the main fuse F106 which is the origin of ignition switch pin 6 and normally via ignition switch to Terminal R and 15. (And of course that the diargams have the pins correct and that pin 6 has 4 mm2 red wire.)

[Siggy]

I’ll check tomorrow when I’m back at work and let you know. I appreciate the help from you guys, I’m determined to resolve this, it’s just taking me a while because I have to learn so much just to do the most basic things.

[Siggy]

Alrighty....Houston, we have a problem....again.

I swapped out the engine to chassis ground cable. Didn't see anything wrong with the old one, but I know electrical issues aren't always visible. Hooked the battery up, everything came on, like it had been doing (dash lights, etc.).

I plugged the ignition switch in and held it in place while I turned the key and started it. Let it run for a minute, cleared the 4x4 error off the dash by turning the wheel. Most all the light (if not all of them) went away and it seemed to be running like a normal car. I turned the key to the off position and took it out and the car, once again, kept running.

I quickly unplugged the ignition switch and probed the 3 wires, 5,6,7, I think (I'm doing it from memory, so it might be wrong) and they were a little over 1V, while the other pins were at 13.6V. Hopped over to measure the voltage at the fusebox and checked the power on that buss bar and it was 13.6V, then pinned as much stuff as I could that had larger wires, some, I know, go to the ignition switch and they are all reading 13.6V.

Okay, this experiment is over, so I go unhook the battery terminals to get the car to shut off and it won't stop running. The battery is completely unhooked and the car is still running. In the past, that's always cut the car off dead. Not this time. It kept running for about 10 minutes while I scratched my head. I went to grab a wrench to see if taking the positive terminal that's located under the hood (for jumping) would change anything and when I got back out to it, it had finally cut off and all the lights were off.

To recap- no key in the ignition, no ignition switched plugged in, the battery terminals (both of them) unplugged from the battery, and the engine is running.

Words cannot describe my frustration with this thing.