2000 BMW 528

I have forwarded your question to our BMW tech. He will be with you shortly, thank you for your patience

The issue may well be the EWS system and will require faults to be read out from the proprietary BMW software to have accuracy. So you can be prepared, it may require replacement of the EWS module and/or the key(s), replacement of the DME, the antenna ring, and the list goes on if the diagnostic is inconclusive.

[quote:1dac2529cf="Dr. Hagerty"]The issue may well be the EWS system and will require faults to be read out from the proprietary BMW software to have accuracy. So you can be prepared, it may require replacement of the EWS module and/or the key(s), replacement of the DME, the antenna ring, and the list goes on if the diagnostic is inconclusive.[/quote:1dac2529cf]

The problem is intermittent, and every time is has happened, I have been able to "fix it" by moving the steering wheel. There are never any fault lights on the dashboard. It is not key specific,. My understanding is there are 2 conditions for the start relay to be energized.
1: Gear selector- not the problem
2: The ring coil, which changes impedance, when there is metal( the key) in the ignition
I am not sure what the input from the DME does, my guess was that was to prevent you from starting the car when it was running.
It appears to be a simple system, with no computer signals involved (no bus) so it should be possible to jumber it out, if you are willing to forego the driveaway protection, or ??

I don't know about BMW software, but for our other car a GM product, it works like that. If there is no indication on the dashboard lights, the computer readout won't give you any information

well, to get an answer, that you have to go to the dealer to get the problem fixed, hardly qualifies as satisfactory.

If there was an answer that was something that would actually fix the car, how would it be for me to withhold that. I am sorry you bought a car that has some issues, I did not cause them and if you have a problem with going to the dealer, then there are alternatives. Try staying in the conversation, I can be a resource or not, it is up to you.

Well, first I did not buy a car with an issue. I have had it for 6 years, and have experienced very few problems.
The starting problem have disappeared for the last 2 weeks, which makes me believe it is in the category of a bad connection or something with the steering lock, because when it happened I was always able to fix it by turning the wheel, and moving it with the lever for vertical and horizontal movement.
I own the Bentley service manual for this model, and having looked at the diagrams, don't see a connection to the onboard diagnostic.
I will live with it for now, and if it ever shows up again, I will let you know what the problem was.

p

Thanks for the response, the issue may be something to do with the electrical portion of the ignition switch. They have a peculiar method of failure. I request you try this to distinguish if there is an issue with said switch, get into the car and insert the key, turn it to the on position, reach over to the passenger sun shade and pull it down and open the vanity mirror, while doing so, is the ABS indicator in the dash illuminating? You may need to be in a darkened area to see if it does because you may not be able to see it in daylight. If it does then the ignition switch is faulty and replacement is in order. Keep in touch mate ♥

I tried your suggestion, but no the ABS indicator was not illuminated. It came on when I turned the key to the run position, but only stayed on for a short time like normal.
I also tried in the accessory pos. but there the ABS light did not come on at all.

thanks for the suggestion, but as long as the problem stayes away, it is hard to pinpoint After all is has only happened 5 or 6 times

p

There are several other factors that can be in play here, what is the condition of the battery, are the cables tight, is this problem chronic or does it just occur once in a while? (Your post said 5-6 times) Have you another key to try? Let us know.

As mentioned in my previous mail, it is not key specific, it has happened with both keys. It is not a battery or battery cable problem.
If it happens again I will install a control light, where the wire from the key switch connects to the EWS, and where it exits the EWS, in order to pin the problem down.

p

The connection from the key to the EWS is through the antenna ring and the connection to the EWS unit from the DME is a digital signal and a rolling code is used to help prevent theft. I am telling you this because you are quite obviously willing to attempt this repair, and I acknowledge you, but you may not understand the scope of what signals are present in each of those circuits, and without an oscilloscope you will be going in there blind, the signals will be meaningless to the lay person.

There are more than one connection from the key to the EWS. The antenna ring signals are logic one or zero, but the connection from the switch is simply 12 volt from F114 to connector x1659/3 and out on x1659/1 and from there to 2 relays in the starter unit. One relay is connected to ground, the other get connected to grounf via the DME.
I am not a lay person, when it comes to electronic, I do have a scope if it is necessary. The problem has not returned, but if it does I know enough about the circuit now to pinpoint it.

p