Car will start but won't shut down

johnnym626

Hello my daughter has a 2006 Rendezvous, she came home and told me her car wouldn't shut off so I went out and looked the key you could take out and it would still run so I pulled a fuse to shut it down, anyways I replaced the ignition switch which I thought it was the problem, no of course not that would be to easy so I went and got a new ignition lock and had her key mated to it went out put the lock back in and it started on the first try(always ran good) anyways I turned it off but it kept running had to pull a fuse again to shut it down to say the least I am dumbfounded now any one have any idea's to put me on the right path

Mr_Shiftright

No easy answer here. Some possibilities would be a sticking relay energizing the ignition switch, or feedback through the alternator. You might try disconnecting the alternator and then seeing if it still does it. Otherwise, you'll need a wiring diagram to get started on where this renegade current is coming from to keep the ignition switch energized. I even read about one wild tale of this being caused by a brake light switch, but never quite understood the particulars of that one.

johnnym626

Thanks I got a diagram but it's a bit cold to be out there as I have no room in my garage, I have never came upon this problem before

Mr_Shiftright

It happens. If you google around you'll meet people with this very problem---unfortunately, no one solution prevails.

thecardoc3

Which fuse are you pulling to shut this down? How accurate is your voltmeter? The reason I ask that is the first step of this is to prove if you are opening the circuit that is using false power, or the one that is creating the false power to keep the car running.

First identify which fuse block terminal is the one that feeds power to the fuse key on engine off. (KOEO) With the problem occurring you need to measure across the fuse contacts with your volt meter's lowest setting. You will get a very small voltage, something on the order of 4.0mv ( .0040) or less in most cases. What is important for this first step is the polarity of the voltage in relationship to which connection for the fuse gets normal system power. Put the positive lead of your meter to the connection that should have power and the negative lead to the one that the fuse protects. Now is your meter reading a positive voltage, or a negative voltage?

A positive voltage means that power is being input to that fuse from another circuit that shares the same output from the ignition switch. A negative voltage indicates that the problem is being created by a failure on that protected circuit. This starts to narrow down which circuits need to be tested further and which ones don't.

johnnym626

Read another forum guy stated that the sunroof leaks down into the glovebox and then down to the fusebox , which then makes all kinds of gremlins she has had trouble with a few things here and there would that be the cause of her car continuing to run after shut down?

Mr_Shiftright

Well if the premise is that the water is conducting electricity from one circuit to another, then that doesn't really add up because this apparently happens all the time. I suppose something could have fried in the fuse box or behind it but that's a rather imprecise speculation. Identifying the mystery voltage-feeding circuit is the key here I think.

johnnym626

Well after sitting for a bit the battery needed charging so I opened the hood to put my charger on it and noticed her power box had fallen forward, she had a power steering unit installed about a month or two ago and they had broken the plastic piece that held the box to the inner fender and the way it shifted let the wiring harness contact the idler pulley and had cut through some wires, after splicing the wires back together charging the battery I am now happy to say that it starts and stops as it should, I had been under the hood several times and hadn't noticed it think I might need new glasses

imidazol97

Thank you for reporting back to us that you did find the problem.

I think I'd talk to the folks who did the power steering repair that their tech or they
themselves broke something and hid it instead of reporting it so it could be fixed.
And that it caused major problems which could have been even worse. LOL

thecardoc3

imidazol97 said:

I think I'd talk to the folks who did the power steering repair that their tech or they
themselves broke something and hid it instead of reporting it so it could be fixed.
And that it caused major problems which could have been even worse.

Is the fact that it got broken during the power steering repair a known, verifiable fact (in that they reported that it happened) or just an assumption?

johnnym626

They were the last people to work on the vehicle as I was out of town at that time, as it's repaired now we'll just not use their services again

thecardoc3

johnnym626 said:

They were the last people to work on the vehicle

Which doesn't prove that they had anything to do with it.

johnnym626 said:

I had been under the hood several times and hadn't noticed it think I might need new glasses

LOL, the older we get, the worse the eyes get.

Most wouldn't pick this off, but there s a common theme here. You assumed the ignition switch was the problem, and when that didn't fix it you then guessed that it might have something to do with the key. Then it was possibly a water leak damaging the fuse block. At this point blaming the shop/tech is no different than those other assumptions. Sometimes things just happen and it doesn't have to be any ones fault. FWIW. The power steering pump, as well as the power steering gear are both serviced from underneath the vehicle. There is nothing that would be done from the top that would be involved in either repair operation beyond add fluid.

johnnym626 said:

as I was out of town at that time, as it's repaired now we'll just not use their services again

Suit yourself on that one. If one goes with the assumption that they have been falsely accused (remember no proof has been provided) what are they really losing?