I had no symptoms, other than I knew my air pump relay had badly burned contacts ......
I bought mine from seller moe333333
I don't see any more at $35, but he does have one at $65 :


http://www.ebay.com/itm/97-MERCEDES-E320-FUSE-RELAY-MODULE-210-540-00-72-LJ0057-J-/230863076864?hash=item35c082fe00&item=230863076864&pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr

 

While I applaud the use by members here of cheaper parts such as the RCM. I would be careful that although the part looks the same except for the part number one obvious difference is the first fuse beside the 40 amp fuse, the OEM part uses a 20 amp fuse in this position.
Having trouble later a person could be forgiven if they never check these fuses while looking for the cause of their problem.
The correct part is;
Relay Control Module
MB #170 545 03 05
Mopar #5099007AA

 

Dave, while I did get the 210 540 0072 module, I removed the cover and compared to the 170 545 03 05 that was in my roadster.
They were identical, except for that one fuse you mentioned.
I swapped that fuse into the 210 module and installed it, it functions fine.
( I do have the 170 module as a spare now, with the air pump relay replaced. )

I'll probably swap them again, as my 170 has the "me so horny" mod.

 

Got it. Thanks for the intervention, onehundred. With all this said, does it make sense to you forum members to make this move? I know ~$100 isn't a lot of money to risk, but I would still like to make sure this approach is logical. Please let me know. Thanks!

 

As I previously posted, were it me, I'd go kiss up to someone at Autozone, Advanced, NAPA, O'Reilly, CarQuest or PepBoys and see if they would let me 'test' a new battery.
Tell him/her that you'll buy it if it fixes the problem, and you'll slip them a sawbuck on the side for the trouble.

The battery in out car is easily accessed and replaced, 5 minutes tops ......
( negative off, positive off - positive on, negative on )

 

I am not sure what the difference can be, MB does not change the number of a part for no good reason. If a part fits another series of cars the number will not change from its original number, if there is a slight upgrade then the last four numbers are the first to change, a small change would be a change in the last two numbers.
Basically if a part was made for a very early car and it fitted a modern car with no alterations to it the number would be the same. Same number = same part.

I do not think there should be another identical part in the system with a different part number, although I'm sure it could happen.

 

No argument, I just know it worked for me.
This is not to say others won't have a problem ......

 

I can sit here and stare at my 170 545 03 05 part that is my spare, hope I will never use it but it goes in the trunk most of the time. It cost me $45, a bargain with pristine contacts.

 

Yes, you are one of the lucky ones, I am simply an old Alabama redneck that gets by the best he can.

You used to have a Concorde, right ? Did you ever have to change the right front marker light ?
I just did on mine : ridiculous !

You have to remove the right wheel, then the fender liner to get to the bulb.
I don't even want to mention trying to replace a headlight bulb.

 

Of all the things that went wrong on that Concorde, I do not ever remember replacing a bulb. Despite the problems it was a nice car, the LHS was better but by no means perfect.
Luckily my wife worked at a Chrysler dealer and everything was fixed under warranty or at $20 an hour, with parts at cost.

 

The OEM RCM came in yesterday, which took 5 minutes to install--much more favorable in comparison to the $230 the dealer wanted to "install" it. It's plug 'n play. Alas, it will be another waiting game to see if this remedies the issue. Next on this list is the MAP sensor. Stay tuned.

 

It's an assembly when the line gets the part so if a fuse value-or anything functional- changes, the assembly p/n would change.

 

Engine shut down, would not restart. Several corroded ground points and corroded terminals. Indicated bad crankshaft position sensor. Replaced with new one from NAPA. Started to have the same problem misfire & shutdown at 4500. Installed new Bosch Double platinum plugs. After installation, engine would not start, no ignition spark. Reinstalled the old CPS, fired right up. The NAPA CPS had a significantly higher resistance when measured with multimeter. Took it back to NAPA for analysis. Awaiting results. I also had several issues at the same time. The corrosion was the primary problem and the second problem was introduced by the faulty NAPA CPS.
I'll update this when I get an answer from NAPA.

 

Its been said go BOSCH, or go home. These cars seem to only like BOSCH CPS's so if your replacing one, buy BOSCH.. I don't work for them, I don't own their stock, and I go by literally hundreds of members who have learned the hard way to just get BOSCH CPS's. Good luck!

 

Lately I've been wondering if the true Bosch difference is fatter connection pins ?
I really can't see a coil around a magnet ( that's all they are ) going bad all that often.
Maybe if you flowed some solder on the Chinese connectors ?