540i won't crank... no fuelpump feed from DME

[yaofeng]

You need to first find out the build date. It determines whether it is EWS or EWS1. Next find the EWS documentation to do the diagnostic. It is online somewhere.

The starter immobiization relay is located on the left of the driver footwell.

[genphreak]

Hi all,

Would anyone be able to help with a problem on a '95 540?

The engine won't start... no fuel pump running. No power at the fuse. Checked the fuel pump relay- all pins are good except for the feed from the DME. I guess this is straight from the Motronic box.

If the Motronic is not pulling the fuel pump circuit up, is it because something in the car's security system (if it has one) is halting it? I don't know what the modern e34s have, but I read that there may be a EWS unit behind the dash? There is no security system under the rear seat, just the battery an EDS unit on one side, airbag sensor in the middle, and then the relay and GM box on the other with nothing in the least being security related.

I think the older e34s use the code feature in the OBC to disable Fuel Pressure and also (perhaps thus) the starter motor.

Does the EWS on a '95 connect in to this also?

Is there a way to reset it?

The car was starting until I disconnected the battery. On re-connecting it the car wouldn't crank. Dashboard lights etc all work properly it seems, and the coolant pump (and power in the engine bay all seems to come up as as it should).

It has the modern remote key-locking system (EWS?) a la e36 and the central locking is stone dead. The keyfobs don't remote operate either of course- but the car did used to start regardless.

Now the starter and fuel pump are stone dead.

Can anyone suggest what to check?

Already checked:
- Full power at the battery (13.7V- jumped with another, still nothing)
- Extar ground strap to the motor (before I realised there was no power to - the FP relay)
- All fuses (Fuse 23 (FuelPump) dead- but fuse not blown)
- Main relay (provides power to the ebox relays as it should)
- Trunk harness (the wear problem seems fixed on the 95 models...)

Many thanks in advance, Nick

[Ferret]

A '95 is almost certainly Transponder EWS driven - do you have an alternative key that you can try?

My '94 E34 TDs did this to me at one point, I took the battery cables off again, shorted them out and turned the ignition to start. Reconnected everything and it just started working again.

I have heard somewhere that if you lock one of the later E34s with the remote and then open with the key, it'll not start.

Sounds stupid but have you tried locking and unlocking the central locking before attempting to start the car? Even with the key?

If I remember correctly, on Transponder vehicles there is no immobilisation relay - it's driven directly from the ECU and no amount of jumping power to the starter or fuel pump relay will start it. You can tell if an E34 is transponder immobilised - there's a black plastic ring around the ignition barell that sticks out slightly.

[yaofeng]

I was wrong.

EWS 9/93 to 12/93
EWS1 1/94 on
EWS2 1/95 on

You have EWS2. And Ferret was correct. There is no SIR on EWS2 equipped e34. I downloaded the EWS description documentation in pdf somewhere online while I was troubleshooting my electrical fiasco right after the 6 speed conversion. PM me with your email address if you cannot locate it. I can send you a copy.

[genphreak]

You need to first find out the build date. It determines whether it is EWS or EWS1. Next find the EWS documentation to do the diagnostic. It is online somewhere.

The starter immobiization relay is located on the left of the driver footwell.

Thanks yaofeng- I knew I could count on you to chime in Should have said what month she was; she's a 5/95 540i 6 speed. I'll get to hunting....

OK- found the official EWS bible over at unofficalbmw.com - it explains the operation of all EWS systems. Looks like I will need t check that the EWSII reciever and power locking module are getting good power and ground.

Does anyone know where the knee bolster is- under the steering column?

" On E34 models the module is located on the drivers side of the vehicle behind the knee bolster."

Thanks for letting me know where to start...

[Tiger]

First of all... check your starter to see if it works. All you need is a remote starter button... and go to your diagnostic module in engine bay... I don't remember what pins... just two... and trigger it to see if your starter crank. You could use just a piece of wire too. Winfred mentioned this on other post.

Otherwise do it the hard way, at the starter... one big cable is the battery positive. Connect one wire to here... and then there is two little terminal, find out which one is positive and hook up the other wire to there.. Then trigger it.

It is possible the starter relay is bad... which I believe is under your back seat... or your fusible link is burned out.

[genphreak]

A '95 is almost certainly Transponder EWS driven - do you have an alternative key that you can try?

My '94 E34 TDs did this to me at one point, I took the battery cables off again, shorted them out and turned the ignition to start. Reconnected everything and it just started working again.

I have heard somewhere that if you lock one of the later E34s with the remote and then open with the key, it'll not start.

Sounds stupid but have you tried locking and unlocking the central locking before attempting to start the car? Even with the key?

If I remember correctly, on Transponder vehicles there is no immobilisation relay - it's driven directly from the ECU and no amount of jumping power to the starter or fuel pump relay will start it. You can tell if an E34 is transponder immobilised - there's a black plastic ring around the ignition barell that sticks out slightly.

Pearls of wisdom Ferret- thank you.

I can see now she is transponder immobilised.

I have 2 transponder keys with 2 buttons each- neither have any effect- the Red LEDs light alright. But the power locking is out as it was before I disconnected the battery... so it is hard to see if they work or not, or to try unlocking and re-locking the central locking.

Shorting the battery sounds promising...- I'll give that a shot (is it not dangerous to the ECU, or other things?) I am having awful visions of the airbags blowing when I connect the terminals... LOL!

Nick

[Ferret]

Shorting the battery sounds promising...- I'll give that a shot (is it not dangerous to the ECU, or other things?) I am having awful visions of the airbags blowing when I connect the terminals... LOL!

Lol, dont short the battery, you'll blow yourself up

It's effectively a 'shogun reset', should electrically reset all the systems in the vehicle, not just auto gearboxes.

There's a guide in the vehicles manual about resynching the keys to the vehicle, IR keys like mine?


Try locking-unlocking the doors on the car with the key before attempting to start it the first time

[genphreak]

Yea... what is a knee bolster.... the cover under the dash above the knee? I didn't see no EWS module in there...

[genphreak]

Doh! yes I meant to say short the batt terminals... Thanks for the pic- I'll give all this a shot forst thing in the morning. Yes my keys are just like that. I don't have a manual though... so no User instructions to go off...

I'll try to connect the terminal connectors without the battery in the circuit for a little while- and se what happens! I sure appreciate the help Ferret, thanks!