OK, here goes. I had the SKREEM issue so I sent the ECU to Josh @ Mercedes Swap Shop. He did an excellent repair and a hot tune as well. Reinstalled. Then I had the dreaded RCM won't crank issue. Sent RCM to djtighe1. Very quick and awesome price. Reinstalled. Car ran great. Had/have a parasitic electrical draw so I disconnect battery when not driving. I went to start it up and got the no start issue again. No crank, fan spins up to hyper speed. RCM relays do not close with key on. I'm pretty sure the RCM is good. All fuses on module are good. I guess the next step is to find where the RCM gets it's power. Does anyone know where/how to check incoming power to the RCM?

 

IF you're still having a parasitic draw, have you removed the alarm siren? That's the most common draw. The batteries inside corrode and cause a short.
You can try removing the number 9 fuse in the engine fuse box. Charge the battery using a trickle charger and then see if you have the issue after that.

 

Thanks for the info. Years back I had the alarm buzzing but I dont remember if I disconnected or not. Now if you can solve my RCM issue I'll be golden😁

 

I found a diagram showing where the power source for the RCM is.
I've made a picture and I'm adding a link to where I found the information. (See figure 10 in the link).
RCM info.

 

Thanks for the additional info. I found the wiring diagram but haven't completly deciphered it yet. It seems the RCM draws power from a splice block 100. Since it also supplies power to several other items, I'm assuming the block is good. YouTube mentioned to check the actual pins on the RCM connectors. I'll check my input power on the points you indicated and let you know.

 

I just thought of something, that might help or not.
When I replaced mine, I had a hell of a time getting a few of the connectors off. I wonder if maybe a wire got loose on one of your connectors?
Good luck!

 

Thanks for the response. Checking the wires/pins on the connectors (as well as checking input voltage) is my next step. Can't get to it until Saturday. Just interesting that one day it starts, next day it doesn't.

 

Pictures of the wiring color codes before taking the connector apart helps in case the wires get shuffled around. Do one connector at a time. One of my connectors had three defective connectors inside it (the tip separated from the crimped on connector at the 90 degree tip, result was an intermittent no start). Good luck!


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I remember that thread. I believe those connectors were available somewhere.

 

It depends on the size (there are two different sizes in the harnesses on the RCM). The part I needed was THE LARGER ONE OF THE TWO (see below, I am not sure IF I also had the smaller one part number in the data. Hope this helps!


Part Type: Electrical Pin Connector
Part Number: 0035452626
Interchange: Part Number 003 545 26 26 / 0035452626
Weight: 0.01 lbs
Size: L x W x H 0.2 x 0.2 x 0.6
Part #: 0035452626
Mfg Part #: 0035452626


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Interchange Parts for MERCEDES-BENZ 0015453526 (replaced by) 0035452626:

Brand:

MERCEDES-BENZ 0035452626 Contact Sleeve
HERTH+BUSS ELPARTS 50253920 Contact Sleeve
HERTH+BUSS ELPARTS 50253925 Contact Sleeve
VALEO 914123 Contact Sleeve
AUDI 447972980 Contact Sleeve
PORSCHE 99965243712 Contact Sleeve
VOLVO 1212901 Contact Sleeve
VW 447972980 Contact Sleeve

NOTE: EAN: 4026736017002


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Another reference part # set:

P/N: 0035452626 Genuine Mercedes

Cross References: 0005452726
0015453526
0015453726
A0035452626
W01331642245


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It has been quite a few YEARS since I needed these, not sure if the data is still correct anymore (but) someone could have them, somewhere. Hope someone can use this?


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Thanks George!

 

Hopefully I'll never need it, (I think mine may have already been worked on by DJ) but this is in my trunk now.