UPDATE 6/22: The Mercedes Swap shop has diagnosed it as another (#3 for me) bad SKREEM module. This time something they have never seen. The module appears to have reverted itself to an older software version, causing a intermittent start authorization. Got the ECU & SKREEM reinstalled today and she fired right up !!


Car ran fine. Started, died immediately. Then, no crank. After about 30 tries, got one more start but died immediately. Car will not crank.

-RCM soldered by DJ Teigh, backup new RCM was tried.
-Battery is brand new(4/22), full power, no dimming lights
-No check engine light codes
-Unhooking the battery then trying yields nothing (skreem symptom check)
-SKREEM fixed 1st by SOS in 2019, went bad again in 21’, then fixed by Mercedes Swap Shop.
-Bypassing the clutch interlock switch yields nothing
-Power is getting TO the Clutch switch
-Power is getting TO the Pulse Module FROM the clutch switch
-If I close the Pulse Module relay by hand that feeds the starter, the motor cranks
-If I get the starter to crank, with somebody holding the clutch down and the key in the “start” position, it cranks, but does not fire up.
-Brand new (5/22) BOSCH Crank Position & Camshaft Position sensors, MAF, & MAP sensors.
-No blown fuses.
-Fuel pressure (Schrader valve full)
-Spare key did not work
-Siren was removed in 20’

 

Have you replaced the CPS?

 

Yes that is listed in the things done prior. Brand new 5/22 was replaced.

 

Only use Bosch parts for the CPS’s, crank and camshafts. The others seem to fail quickly or not work at all straight out of the box.

 

Yes, they are both brand new Bosch units as listed. Thank you.

 

UPDATE 6/22: The Mercedes Swap shop has diagnosed it as another (#3 for me) bad SKREEM module. This time something they have never seen. The module appears to have reverted itself to an older software version, causing a intermittent start authorization. Got the ECU & SKREEM reinstalled today and she fired right up !!

 

Thanks for letting us know. Are you going to get a spare one or did Josh have any other suggestions?

 

No suggestions and No spare unfortunately. I was told “Should be fine after this”. Now MSS did an amazing job twice nice, by no means am I dissing them when I say this; I blame the entirety of this overly complex system on Mercedes and if this happens a 4th time I will 100% be contacting Precision for the SKREEM delete.

 

i am having the "no start " issues. sent out the skreem to be refurbished. came back, same problem. sent it back & they said it checked out OK. next , took out the RCM, it looks perfect. the soldering looks great. is there anyone in the metro NY area that knows my 2007 crossfire limited ? HELP.....thanks Dog

 

The RCM can also be bad or sticking relays, not just bad solder joints.

 

Is it cranking or no crank ? Relays could be back if it’s not cranking. If it’s cranking and not starting could be your crank position sensor, cam position sensor, or maybe fuse #30 or #32 ?
Also if no crank, verify ur ignition is sending power to your clutch switch and your clutch switch is sending power to the pulse module !

 

cranks over 2-3 times then nothing. had the skreem sent out...fixed, then re-checked. how do you test the RCM ? Or do crank position sensors have the same symptoms ?

 

Open the RCM. Reinstall. Turn key to the ON position. 2 of the 3 middle relays should remain closed. The fuel relay should close for 2 seconds, then open, when the key is first turn to the ON position.