Back at the mechanic again keeps dying. I will be driving along and the car just dies. Sometimes if I wait long enough it will restart. It always starts again the next day. I had it towed five times to the Mercedes mechanic when he finally went to the crossfire forum and found the answer. Of course I don’t remember what it was...something about soldering on the board not being good. Update: I just called him and he said he resoldiered something on the Sam module. He fixed the problem and it was great for two years. I was on my way to MD Anderson Cancer Center when it died again in the middle of nowhere. Why does it always die in the middle of nowhere? Had it towed to the closest mechanic which was not close and I told him about the soldering issue and they fixed it and it lasted two months. Now it’s back in the shop again. Do you guys have any suggestions? I’m smack dab in the middle of cancer treatment and I really need to have a reliable car to get me to and from Houston.

 

Get a new Relay Control Module if that is what is causing the trouble. They start at $130 or so.

 

I ordered this one through amazon. It's up to $147 U.S. dollars now.

The RCM has more than bad solder joints to be concerned about. The relays just wear out and get pitted/bad contacts with time. Tighed1, here on the forum, can refurbish your old one. He offers fast turnaround on it, too.

I also sent my old one to tighed1. You could buy a new one, then send the old one to tighed1 for refurbishing. That way you would have a spare to carry. It's quick and easy to swap out. Here's a link to the sticky:
https://www.crossfireforum.org/forum...-no-start.html

If there are other symptoms, then just share them here. Someone will help you figure it out....take care.

 

1) Yes, order a new RCM and put it in yourself. (They literally plug in, without ANY tools, altho a flat blade screwdriver helps make it easy to unplug the connectors from the old one).
Then mail the bad RCM to DJ and have him rework it, that way, you have a spare.

Now, it may not be the RCM, it may be the Crank sensor - you did not indicate if, when the car dies and won't start, whether or not the starter engages. If the starter engages but the car won't start, it can be the RCM or the Crank sensor. If the car won't even engage the starter, it's the RCM.

Id' order a crank sensor as well, in fact I'd order two, the Crank sensor is a part you should also have a spare for - I sure do.


Here is the RCM, order it today:
https://www.summitracing.com/parts/s...AaAoMDEALw_wcB

Crank Sensor - order the BOSCH at the bottom of the page (if you order the Bremi or the 'OEM" part, please don't ask for help here ever again):
https://www.germanautosupply.com/cat...nkshaft.Sensor

2) Stop taking the car to a "mechanic" and expecting him to fix ANYTHING. There is no factory support for the Crossfire, if the guy does not know that it's an SLK320, he will be lost. If he does know it's an SLK320 but has no experience with them, he is going to be lost.

 

As others have said, replaced the RCM with a new one and pop it in. Its simple. These cars are reliable if you don't do hack job-type repairs.

 

sgnorris
I can refurbish your relay control module. As mentioned it's not always just the solder joints. The relays go bad causing starting and running issues.
If interested email me at tighed1@hotmail.com for the details.

Also interested in if the car is cranking (turning over) when you attempt to start when the car dies.
Sounds like you may have a crankshaft position sensor problem.