Magnetic Pickup Ignition Control Module for Mercedes

[Electrobrains]

So, I got my hands dirty and was able to localize the electrical problem of our old Mercedes bus!
It's the Ignition Module: A Siemens type called 0035451732

It looks like this:

Here is another brand that I suppose would be interchangeable (Beru ZM004):

I have also found some connection diagrams on the web, that I think applies to our bus:

I found out that I can buy those units for €100+ which I decided I will definitely not do.
The content of that box cannot be very complicated.
So before I start cracking it open, I wonder if some of you have knowledge and experience with this type of unit? Any simple circuit diagram available?

I have looked at some specially dedicated IC's like the STM types L482 and L484. Those circuits are no longer so easy to find, although I found some on Ebay.
The problem is, I need to get the bus going for the weekend!

 

[KrisBlueNZ]

Sorry to rain on your parade, but...

We're talking about an automobile here. There are safety and insurance considerations. If an accident occurs, and you have used anything other than manufacturer's genuine or manufacturer's recommended replacement parts, this may nullify your insurance and make you legally liable for any damage, injury, or death that may occur, whether or not it can be proven that the replacement part had anything to do with the accident; even if other parties were entirely at fault!

Using a home-made component would make the situation far worse.

The proper part is designed in conjunction with people who know intimately the operation of the vehicle. No one else can truly say that they know everything they need to know to ensure that any redesigned part is completely suitable for the application.

Every aspect of the original part is carefully designed, including its physical robustness. Something you make yourself is very unlikely to meet the original part's standards.

If you could make a suitable, fully specified replacement part yourself, it would cost you far more than the cost of a genuine replacement part, because of economies of scale and production manufacturing.

Anyone who tries to help you with this project could be putting themselves in legal jeopardy.

Other electronics forums have rules against automotive modifications. Electronics Point doesn't, AFAIK. I guess that's because the administrator(s) aren't aware of the legal and ethical risks yet.

In other words, I don't know of ANY reason why this would be a good idea, including your implication that you could save money by doing it.

 

[CocaCola]

My question is why not just get the OEM or OEM equivalent replacement? Yeah it's expensive but it's not like it's not available anymore... Get the right part and you know it will work as it's supposed to... I did a quick search on the original part and it appears that same module was used in Toyota Corollas (and many other vehicles worldwide) at that time so it's actually a common part... A quick search on a local auto parts store online showed it in stock for pickup at the store 5 minutes down the road...