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Does the CEL usually come on when the CPS is failing? Mine stalls almost daily now that the weather is warm but never trips the CEL. I have a replacement sensor and OBD scanner ordered. My understanding was the CPS rarely trips the CEL.
Went out today to test whether or not they relays are closing. I had someone watch as i turned the key, and all 3 middle relays close when the car attempts to start. The one next to the fan one engages then disengages a second or two after i attempt to start it up though.
Does that mean the RCM is fine? and that it's a different issue? I had the battery disconnected for 10mins or so while I was getting the RCM situated and the car never attempted to start back up, so I don't think it's the SKREEM module.
That would be the fuel pump relay, it most likely disengages because the PTCM detects that the engine did not start, therefore the fuel pump is no longer needed. But I could be wrong, just seems logical.
Have you tried spraying all the relay contacts with electronic contact cleaner, in particular the engine control relay ?
...and all 3 middle relays close when the car attempts to start. The one next to the fan one engages then disengages a second or two after i attempt to start it up though.
FYI - I had the same problem with a 2007 Roadster - SKREEM replaced twice and PCM once. And today, my 2004 Crossfire coupe has the same symptoms as roadster had last year, I suspect it is the SKREEM problem. Chrysler must have made a terrible SKREEM module.
Originally Posted by KrisFire
I just went out and disconnected and reconnected the battery and it won't attempt to turn over at all. Swapped back in what I thought was the bad rcm and still nothing. I read at some point you could manually close the relays on the board to test if they were bad. Would that be an option?
Well I'm not saying you're wrong so let me give you some examples of what mine did, never fail to start when it was cold, on occasion it would stall when you came to a light or stop sign, sometimes it would start right back up but most often it would do nothing, no starter engagement no click no nothing, let it sit for 15-20 minutes and then most of the time it would restart, sometimes after driving for just a few minutes I would shut it off go in and run an errand and it would just turn over but engine would not start, would have to reset by removing negative battery terminal, in all of those times it had only thrown a code once , and it was the crank position sensor code. So I honestly don't know what to tell you these cars are very very quirky. When I pulled it out it was the original CPS still had Mercedes Benz on the side of it 11 years old and 110,000 miles.
Got the repaired RCM back today and put it in. Car won't attempt to start. What else could this be? Going on two weeks without the car and I can't do this anymore. Gonna have it towed into the dealer tomorrow if I don't get some more solutions tonight.
Is it a manual or an automatic ?
If manual, check the clutch switch.
If automatic, might be the pulse module.
Car is a manual. I called the local Mercedes dealer and they've got the switch in stock for 21$. Gonna go get it tomorrow morning and see if that fixes it. If not, I've already made an appointment to have the dealer look at the car.
By chance does anyone happen to know of a writeup on where the switch is located and how to change it? I'll try and find one by searching.
You can download a service manual for you car ,on the forum. Free! This will help with all future projects. They are a great to have ,when your under the car an think, "now, what was I doing"
You can download a service manual for you car ,on the forum. Free! This will help with all future projects. They are a great to have ,when your under the car an think, "now, what was I doing"
I took a look at it last night, but couldn't find the section on replacing that switch. I've got the under dash panel removed thanks to the knee bolster removal thread, and am gonna go get the new part. Maybe once I know what I'm looking for I'll be able to see it.
So of course the dealership's system was wrong and they didn't have the part it said they had. After doing some poking around under the dash I can see three different switches. Two of them that are on the clutch pedal and one on the brake pedal.
The two on the clutch pedal are the same switch/part number, but it looks like one of them is always open, and one of them is always closed. One has a red w/black stripe on it and a brown wire going into the connector, and one has three brown wires coming into the connector. Does anyone know which of these two control the start sequence? I've got only one ordered, so when I get it tomorrow, I want to know which I need to replace in the hopes that I get the car working.
Edit: I just borrowed a multimeter and checked the switches. Both have no resistence when opened and do show a resistence when closed. That should mean they're both functioning properly? Could it be the connectors themselves going into the switches?
Picked up the new switch this morning. Installed it and added some dielectric grease to the contacts of it and the other switch that was down there. Also took the battery over to O'Reily and had them test it. It came back good. Put the battery back in and tried to start. Attempted to start this time twice.
I'm having it towed into the dealer tomorrow morning. At this point, I've run out of options/patience and am pretty sure it's the SKREEM module. :/
Chris could you let me know if it is the SKREEM module. I have my 04 coupe stuck at my work garage. No click when try to start however everything lights up. Last time my 2007 had the SKREEM replaced in 2015 and then had to replace one year and 7 days after the SKREEM and PCM -- took dealer 7 1/2 months to figure out what it was. Good luck.
Picked up the new switch this morning. Installed it and added some dielectric grease to the contacts of it and the other switch that was down there. Also took the battery over to O'Reily and had them test it. It came back good. Put the battery back in and tried to start. Attempted to start this time twice.
I'm having it towed into the dealer tomorrow morning. At this point, I've run out of options/patience and am pretty sure it's the SKREEM module. :/
Am I wrong in saying that Dielectric grease should not be used on the metal contacts because it acts as an insulator ?
Am I wrong in saying that Dielectric grease should not be used on the metal contacts because it acts as an insulator ?
That is what I thought to some degree but after searching on the subject I found it not to be true. Evidently the grease is pushed out of the way and the metal to metal contact is not impeded.
See this article as a sample on the subject. Maxichon is an expert on this and hopefully he will chip in a comment.
Re: Car Won't Start :(
