Chrysler Crossfire
RCM, Relay Control Module

This is one information page of my collection of what I have repaired on my Crossfire.

Note:
You should not do any repair on your car if you don't have enough experience and knowledge! You use this information at your own risk! Don't blame me if something goes wrong.

Content:

• Main Content Chrysler Crossfire DIY
  1. Locate and removing the RCM module
  2. Check for faulty devices
  3. Soldering the circuit board
  4. Mount the RCM back in car

If you have a Mercedes SLK R170 with a 320 engine it's almost exact the same.

Note:
You have to work with the electric parts when removing the RCM module. Disconnect the battery, the negative terminal ! When disconnecting the battery the alarm and radio will be reset, be sure to have any codes that's needed!

Introduction:

One evening when I'm was on the way to drive my car it refused to start, it didn't even crank the engine. I couldn't hear any relay for the starter motor click but the dash lights up with its all control lights. Strange never had this problem earlier, but one of the earlier owner told me that she had something similar many years ago. Consulting internet and found information about the RCM, Relay Control Module. It's very common that three soldering points is faulty on this module.

Two days later I was prepared to repair the car, but before I start measuring anything I tried to start it, to my surprise it started directly. Checked the OBD codes, but there where no warnings, good because other problems can be the cam and crank shaft sensors, they give error codes when break. This is a typical malfunction when there is a bad electric connection somewhere. I decided to take apart the RCM module to see what's inside and solder the bad connections.

1, Locate and removing RCM module:

This is how the dash lit up when I earlier tried to start the engine, nothing more happened.

The RCM module is inside the black box in the engine room, close to the battery.

Before doing anything, disconnect the battery cable. And you must have some knowledge about cars and electric system. Otherwise you will destroy something and it can be dangerous too. Take help of a friend who has this knowledge if you don't have it yourself.

Put the battery cable safe aside.

Push the two slider lock mechanism to the front of the car.

Take away the lid, take it slowly and gentle, it can be stuck at the left edge. Deep down where the arrows points you see the RCM module.

You can pull up the big cable and put it aside to the left to get more room. At bottom there is a spring lock, push it gentle to the left and grab the RCM box and lift it straight up.

Next is to loosen the cables, all connectors are different so you will not mix them up. Don't pull at the cable, grab the socket. They can be hard to get out, wiggle them side to side when pulling and maybe it will be easier.

The second connector from left is bigger and can be even more difficult to loosen, take it easy and don't rip of the cable.