Problem of the Day: No Start. WTF?

[BimmerM3inGA]

The battery is brand new. Less than a week old. But I still plan to check the voltage - just to be sure.

[crystalworks]

Originally Posted by BimmerM3inGA

The battery is brand new. Less than a week old. But I still plan to check the voltage - just to be sure.

If the alternator is going out the battery won't charge. Usually this presents itself with a host of other warning lights on the dash though.

[BimmerM3inGA]

Alternator is charging fine. Before I replaced the battery I could jump it and drive a few miles and it would restart with no problem. I also checked the charging voltage with the old battery to make sure it wasn't a charging problem. I don't recall the exact number, but it was very close to 14V with the engine running.

[StephenVA]

Based on that info I would look at the starter itself and the relays after testing the voltage at the starter with key on and in the "Start" position. Looking for 12V

[X53Jay4.8is]

Originally Posted by BimmerM3inGA

So if you've seen any of my other posts, you'll know that last summer I bought a 2002 X5 4.6is that was supposed to be in excellent condition and to serve as my daily driver. However, it has quite literally been one problem after another and I've barely been able to put 2,000 miles on it because of all the problems.

Well, I guess I got cocky because I've been driving it to work once a week thinking that it was actually going to be reliable enough to, you know, drive to work.

My two-week lucky streak ended today. I got in it to head out and it won't start. Everything lights up and switches on when I turn on the key, but nothing happens when I turn it to the start position. I mean nothing. There is no click, the lights don't dim. Nothing happens.

It has a brand new battery - just installed it last weekend. Is the PNP switch known to be problematic in these cars? I've never had a problem with one in a BMW before. But this car has never disappointed when it comes to having unusual (and common) problems. So I can't rule out that possibility.

I really do need to use it over the weekend, so I need to get this sorted asap. Does anyone have a suggestion that I could try? Is there a reliable troubleshooting routine that would help narrow down the possibilities?

On a side note, I sold my 740i M Sport last night because I thought I finally has this POS running reliably and didn't need it as a backup vehicle. I think that once I figure whatever the hell is wrong with it this time, I'm going to sell this one and look for another E39 Touring. But I won't try to sell it here!

My EWS imobilizer gave me a similar no start situation like yours. When you turn the key do you hear any kind of ticking inside the car? Scan the vehicle and see what codes come up. I think if the imobilizer is defective a code will show for it. Don't give up on the 4.6is it just needs to be sorted and of course you are frustrated.

[upallnight]

Got a spare key? Try the spare key.

[Bmwtvboy]

check fuses associated with the module. There is a module that if bad doesn't recognize the key and allows the car to power up, but won't let it start. You can try disconnect the battery and reconnect, but bad modules may need replacement.

[BimmerM3inGA]

Originally Posted by upallnight

Got a spare key? Try the spare key.

I only have one key

[CapeX5]

I had the same problem on my 01. After much work/diagnostics it was the 7.5amp fuse that is related to the DME. There are 2 fuses for the DME. Just look on the directory and you will see them. I am a fan of trying the simple things first. Keep us posted.

[BimmerM3inGA]

God, I hate this car sometimes!

I came home from work and just for the hell of it, hopped in and turned the key. I did nothing else except turn the key and it started right up. At first that seemed great. But then I realized that means it will now be impossible to troubleshoot. Sooner or later it will happen again and may not be conveniently parked in my driveway next time.

So now I'm going to be worried about getting stranded every time that I drive it. Which means that I probably won't want to drive it. So it will sit in the driveway mocking me.

I'm going to run diagnostics on it tomorrow to see if there are any codes being stored. Maybe I'll get lucky (ha ha) and find a clue about what's going on.