[ThunderMoose]

I am hoping the forum can offer some ideas.

The short version - DME will not come on and when it does will not stay on.

Updates from 8/18

* tried to jump DME relay. That didn’t do anything
* with ignition in position 2 tried to communicate to ECU. It would not.
* removed dash to see if there was any obvious issues . Did not find anything.
* at some random point with dash out, the gauges in position 2 indicate DME was on. Was able to communicate with ECU via INPA and start car.
* car will run but not stay running. When it shuts off, I hear it cycling through throttle and am able to instantly restart.

Longer Version Below:

I am at VIR.

Went to start car this morning and it would crank but never fire. Could not hear fuel pump prime, so jumped it out and still would not fire.

At that point I paid more attention to my gauges and noticed red battery, red oil, red brake and pegged out temp gauge. Now I am thinking I have bad DME. Eric Wong is here so I borrowed his DME and still nothing.

Now this is where it gets real weird...I put my DME back in and suddenly the car makes some clicking noises and gauges look good. I am able to start the car for .... 3 seconds ... and then it dies.

Now I start checking fuses and grounds everything looks fine. I disconnected my wide band sensor from the fuse panel at one point and the clicking sounds commence and the car is able to be started. It runs for about 1 minute and dies. It commences to make more R2D2 noises and I am able to drive it up the hill to my garage. It dies several times on the way but always come back after a second or two.

Once I get to my garage, I can not get car to start again. At one point after a couple of hours the the car does some more clicking but then dies again.

Basically, it appears that the DME is not turning on or staying on.

Normally, when you put car in position 2 fuel pump primes and it strokes the throttle. My car no longer does that consistently though it will periodically “turn on” if I leave key in position 2. It’s like it is possessed.

I don’t have a spare DME relay though the green guy next to it appears to have the same function. I swapped that but nothing.

The fusesa next to DME relay are all good.

I checked the ignition switch and it’s good.

Car will crank so I don’t think it is an EwS issue.

My AIM cannot read DME cab signals but picks up DSC can bus signals.

I didn’t try to hook computer up as I don’t think it will even read.

Battery is new. alternator was replaced a couple of months ago. Starter was replaced in June. Car started fine every time in the last couple of months. It stays in the garage.

It started fine when I put on trailer Friday morning. Drove 800 miles from Louisiana to Virginia on trailer. No rain. Though it was hot. When I got it off trailer it coughed but eventually started . But it was not starting this morning as described above.

Throw some ideas at me. Also if you know a BMW specialist (or exorcist) near VIR let me know as I am more than happy to hand this problem off to an expert.

Thanks is advance.

Denis


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[Aeko]

Tossing some spaghetti at the wall here: Check the resistance of the ground paths to the DME? Also measuring the voltage at the DME connector may turn up something. 800 miles in a trailer makes me think a loose connection was not happy with the ride it took. You could also try to jump the DME relay entirely?

[ThunderMoose]

Originally Posted by Aeko

Tossing some spaghetti at the wall here: Check the resistance of the ground paths to the DME? Also measuring the voltage at the DME connector may turn up something. 800 miles in a trailer makes me think a loose connection was not happy with the ride it took. You could also try to jump the DME relay entirely?

I was going to try jumping the DME relay tomorrow.

I tend to think you’re right about connection but I’ll damned if I can find which one. I’ll check grounds tomorrow from the DME.

Keep em coming!


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[eacmen]

1. Have you tried reseating all the connectors on DME?
2. Do you have scan tool or INPA to try and communicate with DME?
3. Have you tried jumper cables or battery charger? I know you said alternator and battery are new, but that doesn't mean the alternator hasn't failed. The clicking noises are indicative of failing battery or alt.
4. Check battery terminal torque and all major grounds.

[ThunderMoose]

Originally Posted by eacmen

1. Have you tried reseating all the connectors on DME?
2. Do you have scan tool or INPA to try and communicate with DME?
3. Have you tried jumper cables or battery charger? I know you said alternator and battery are new, but that doesn't mean the alternator hasn't failed. The clicking noises are indicative of failing battery or alt.
4. Check battery terminal torque and all major grounds.

I did everything but #2.

Even with it on a charger it still won’t turn on the DME.




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[terraphantm]

See if the big ground wire behind the Ebox is connected?

[bigjae1976]

Here is what I know from my EWS delete nightmare. I have an MSS54HP so not sure if it’s different from an MSS54.

After deleting the EWS and connecting pins 1 and 2 it would crank but not fire. Everyone told me it should fire with the fault codes disabled using the ECUWork tool.

IIRC, I had 12v at the fuel pump, relay and all of the fuses near the DME.

Pin 3 out of the EWS is actually a direct connection to the DME through fuse #14. I think the fuse diagram says it’s for the immobilizer. Once I applied 12v to the wire that runs to fuse 14 to the DME, the car fired up.

I’m pretty sure that wire has something to do with firing the ignition and/or fuel pump. Might be a place to start looking.

I’d check the starter and make sure there isn’t anything damaged. Maybe bench test it. Then inspect the flywheel. Rule out physical damage before trying to figure out the electrical.


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[PITT M3 RR]

Add voltage regulator to that list of things to check?

[GerM3n]

I know you ssid you replaced this stuff, but I had a car that acted possessed like that and it had a bad alternator and battery...

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[ThunderMoose]

Originally Posted by terraphantm

See if the big ground wire behind the Ebox is connected?

If it’s the big guy just above ebooks it’s nice and tight


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