mkiv_tdi

Hi all -- couldn't stay away from the MB game. Sold my '06 E55 last summer, and my LX470 needed a companion, so I just picked up an S500 yesterday.

'04 Navy Blue, 160K miles, and totally dead.

But for $1k I figured why not...

So a few hours of research lead me to think that the EIS module might be at fault.

Here's what it acts like today:

1) I put the key in the ignition. The steering wheel motor moves the wheel down to whatever setting the prior owner established.

2) I am able to turn the key to positions 1 and 2, but NOTHING HAPPENS.

3) The car is also completely stuck in park.


Otherwise electronics work. The car has been sitting for a few days and shows 12.43V on the battery.

So is there any way for me to pull codes with STAR? If it is the EIS, are you guys aware of a vendor/company that rebuilds them so I can ship this out?


Some places I came across -- anybody use them?

http://www.ogsmechanics.com/tutorial...er-key-module/

https://www.autotronics.co.uk/merced...r-service.html


Class is wrapping up for the summer after today, so I'll post pics of the new project over the weekend! But as of now, it's a paperweight

tusabes

Most likely the car is water damaged and needs new SAM units .

Instead of repairing eis , the Best thing to do is to get a matched set of key , shifter , eis and ecu from a wrecked car. They must come from the same donor car as they only work together . You can find matched sets in eBay for about $350. That will eliminate numerous potential problem areas . If the car still doesn't work after swapping these 4 parts you an easily resell them for about what you paid .

mkiv_tdi

Well the P.O. had the shifter replaced in the recent past. Claimed his wife "spilled coffee" all over it. And he said the plastic linkage was replaced with a "metal" piece.

Additionally, it had been raining for about 4 days prior to the day that I saw the thing on Craigslist. He said he and his wife came out from dinner, and he was flying on business so they went to the local barns and noble to grab a book for the flight. When they got out of the book store, the car was completely unresponsive.

I towed the car away from the Barnes and noble the following day.

tusabes

With that additional detail Then it's very likely water damage , and not the eis
see here
https://mbworld.org/forums/s-class-w220/265605-2nd-s-flooded-week-s-owners-keep-your-drains-clean.html

mkiv_tdi

That was the first thing I checked for... after being in the rain for four days I pulled up all the mats and everything was bone dry, no smell, no humidity, no condensation.

I found a guy parting out and S500 an hour away... think it's with the risk to buy KEY + EIS + SHIFTER and give it a shot?

I guess I can resell if not those. Do I need an ECU??

Welwynnick

Yes, the key, EIS, TCM and ECU are all paired (sic) together.

FWIW, Autotronics repaired my EIS, though the symptoms were different to yours. The key wouldn't turn at all.

Nick

mkiv_tdi

Right, and I've got:

Common failures:
Key doesn't turn in the Mercedes Electronic Ignition Switch (EIS)
Key doesn't turn in the Mercedes EIS when there's cold weather
Key turns in the Mercedes EIS but the ignition lights on the instrument cluster doesn't switch on
Key sometimes doesn't turn in the Mercedes EIS


How much did that run you?

And I'm still confused... do I need EIS + Shifter + Key from donor car and KEEP my ECU/TCU.

Or do I need EIS + Shifter + Key + TCU + ECU


Thanks!

amstel78

Worst case scenario, you could also part the car out. I'm sure you'd make a lot more than the $1000 you invested.

mkiv_tdi

True. I'll still give it the 'ole college try.

So, i had the day off from work today and, conveniently, an '06 S500 4Matic with 52K miles popped up on craigslist for a part out.

So I bought 2 xenon headlights (mine had broken tabs), and the matching Keys/TCU/ECU/Shifter/EIS unit.

Figured I'd swap them all over from my unit and see if there's ANYTHING different.

As I got to the shifter, this immediately jumped out at me, likely courtesy of the "specialists" that changed the shifter a few months ago.



So, I figured I'd change out the rest of the components, and when I got to the TCU, there was some not-so-surprising oil residue that had seeped up the plugs, so I cleaned that out really well, and finished up the swap over.




Long story short, IDENTICAL results.

Key inserts, spins to position 1 and 2, but no life from the cluster. Shifter still remains blocked in park.

At this point, should I focus on the mangled harness that goes to the shifter? Are there fuses I should focus on?

Everything else works. Radio, Seats, Nav, Headlights, etc etc.

Brake light switch?

I'm determined to get this thing alive.

tusabes

My bet is still the Sam

Welwynnick

The common problems on the w220 are failed EIS, and stuck in park.

With the failed EIS, you can't turn the key, so this isn't that.

With stuck in park, you can still start the engine, so it isn't that either.

You've got a problem with what Mercedes call Drive Authorization, and you need several things to work right.

There's a mechanical cable that runs from the Transmission Control Module (TCM, selector) to the EIS. That forces you to put the transmission in park when you leave, which is the cornerstone of W220 security, as there's no steering lock.

There's also various electronic connections that run to the TCM, and they relay several signals, including park lock. To get out of park, you need a good key, good EIS, good ECU, good TCM, ignition on and foot on foot brake. By good, I mean present, correct, connected and matched to the other parts. One of them has gone wrong, and it sounds like it's not the EIS, ECU & TCM.

Can I ask what happens when you turn the key to position 2 and put your foot on the brake? Do you hear a click in the selector module? That's what normally happens when park is unlocked? My guess is you don't, but I wanted to ask. Maybe you've got a bad brake light switch (remember there are TWO) but that doesn't explain the lack of ignition.

It does sound like you've got a power supply or connection problem, so I think I would start with the fuses. That wire bundle may be the cause, but I wouldnt' hold your breath.

Nick

mkiv_tdi

So, did more looking around today, and I found something.

Not sure if it's the cause of my problem, but its certainly A problem.

Blown 60A fuse under passenger side footwell.




SO, what's that thing do?? And what might have cause it?? And does it have anything to do with my current issues??

I guess most importantly, what might have cause it? I don't want to repair if the underlying condition will blow it again..

We'll get it running again, I promise!

Thanks again!!

knowbenz

That 60A goes to EIS. check resistance to ground on that circuit before replacing it

mkiv_tdi

Some progress, maybe..

So I've replaced that 60A fuse. My local Advanced Auto had an identical fuse, so in she went and I buttoned everything back up...

And, LIGHTS! At least the car finally recognizes that the key is ignition position #2.

So let's try and give it a crank...

Still unresponsive. Not even a hint of a click or an attempt of the starter to do something. So I tried again, nothing. And again. Nothing. And again...

SMOKE!







What's this thicker purple wire and what's this plug for?? It got HOT.

knowbenz

Purple wire goes to starter solenoid. Other wires are various circuit 87 wires and such.

ItalianJoe1

Sounds like your starter may be shorted if it's smoking the feed wire (the big purple wire)

I'd check power at the starter and apply direct power, see if it turns over.

wallyp

The actual starter feed wire is much larger - that purple one will feed the starter solenoid, a heavy-duty solenoid-operated electrical switch.

I would start by checking out the starter solenoid and the purple wire. Disconnect the purple wire from the solenoid, then check the upper end of the wire for connection to ground/earth - there should not be a connection with the wire off the solenoid.

If there is no short to ground on the purple wire, check the solenoid.

mkiv_tdi

Okay so before tackling my starter, can we assume my EIS is GOOD?

1. The car recognizes the key.
2. It is allowed to turn to position 1 and 2.
3. When I turn it into the crank position, I get voltage going to the PIN that feeds that purple wire to go to the starter solenoind.

So is my car doing the appropriate "handshaking" for me to assume my EIS is good?

I tested the starter relay, and that works well. And then I tried to jump the starter and apply power directly to it via the purple wire... and I get spark. So there's a short somewhere because the starter is unresponsive.

ItalianJoe1

Yeah if the car is attempting to fire the starter, your system is working.

Check as you said for the solenoid trigger wire shorted (the purple one), and go from there. If the solenoid has failed internally it will do the same thing, it can stick closed and burn stuff up, that's why the fuse is in the circuit.

mkiv_tdi

So my investment has been:

$1,000.00 for the car.
$4.95 for the VW/Audi assorted bolt fuses (of which I needed the 60A)
$0.25 worth of electrical tape and shrink wrap.

I got the car up, and removed 3 bolts to a head shield that was wrapped around the right side of the starter. As soon as that came off, I noticed my issue:



I pulled the purple cable up to the top of the engine bay after removing it off the starter solenoid... It was grounding out on whatever part of the engine in there it was touching. Not sure how or why...



Re-wrapped it and shrink wrapped it..



The replaced the cable, and tested the starter directly again with a spare 12V battery I had lying around. This time, it fired!

So I hooked up the back battery, plugged my burnt plug back in after a little cleaning, and fired her up. Started up on the first crank!!!!!

So I'll either get a new plug, or just repin the plug!

And it'll need a trany service and that 13 pin connector, as well as valve cover gaskets. Otherwise, we're in business!!


I hope this thread helps somebody out, cause i've learned plenty on here

tusabes

That is awesome !!

Btw your pics aren't showing up, says your photobucket bandwidth is exceeded

mkiv_tdi

Re-pinned a "new" plug that I got off a guy parting out his S500!

Also re-uploaded the pics of the status of my purple starter wire!

Got to take it for a ride today -- she pulls really, really well! Makes my LX470 feel like it's moving backwards. Time for a detail in/out, and then some more "tune ups!"

Tranny Drain and Fill + 13Pin Connector
Valve Covers

That's all that looks glaringly obvious as needed sooner rather than later!