Starter module?

[backseateducation]

Afternoon all.
I don't know if you've seen my continuing woes about my non-starting Project YouWhyWhy, but the garage now thinks it may be an immobiliser issue.
Talking to a guy with a E39 5-series earlier and he mentioned something under the steering column called the starter module (?) could be at fault? Some of the faults the diagnostic has turned up include lack of power to the fuel pump and ignition switch, and something called pin 15?
There is still a lot of butchered wiring under the dash where the alarm system has been ripped out (which has p***** me of as not long ago I paid someone to sort that out.......)
They've also asked if I can supply them with a immobilser wiring diagram - I was kind of hoping they would have access to one (being a garage!), but are these easily available?
I'm sorry if I'm covering old ground here - I wish I could get the car to a meet so one of you knowledgable chaps could look at it, but as it doesn't run at all now......
I'm starting to get really depressed by not having it, I've missed so much good convertible weather!

 

[mrscalex]

They’ll be referring to the EWS. And balance of probability are correct in their assessment, especially if the loom has been messed with.

However if it’s cranking then the issue is after handoff to the DME or between the two, ie rolling code handshake.

The EWS is just a smart relay to release the juice to the starter.

 

[backseateducation]

Brilliant. Thanks a lot, Ill pass that on

 

[Delk]

Mine had an issue with the rolling codes. The starter would turn but it would not give power to the injectors or something. Been years now and Steve helped me. Had to resync the dme and ews and it fired right up.

 

[backseateducation]

This sounds promising. How did you do that?

 

[Delk]

I bought one of impa programs that let your computer talk to the car. It does more then a normal scanner.
Others will be able to give much better advice.

 

[mrscalex]

This sounds promising. How did you do that?

Only promising if the engine is cranking and not starting No crank and it will be EWS - assuming no other major failure like battery

 

[backseateducation]

It does crank over, pretty strongly to be honest. The garage reckon they did get it to run, but i tried it when I went in on Thursday afternoon and it wouldnt do it for me!

 

[mrscalex]

It does crank over, pretty strongly to be honest. The garage reckon they did get it to run, but i tried it when I went in on Thursday afternoon and it wouldnt do it for me!

If it cranks it's not the EWS. It will be something the DME isn't happy with, including the possibility of the rolling code check failing. That's the passkey the EWS sends to the DME to authenticate itself. They can become out of step sometimes and need to be reset. Often from a flat battery.

 

[backseateducation]

Great thank you. As the symptoms have worsened over time (gone from struggling to start, to cutting out, to no start at all), I guess it's just got more and more unhappy. Although as the wiring has been butchered, I guess that's feasible if connections have been breaking down and finally given up.
My biggest issue is that I have absolutely no idea about involved electrics like this, and, worryingly, the garage I'm using doesn't seem to either, so forgive me if I seem a bit panicky.