How to Repair Relay Control Module (RCM) - (Mystery no Start)
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
My car died on me twice while driving. Then I parked it came back and it hasn't turned on since. There is no crank at all when I try to start the car. Dash lights all come on. I extracted my rcm. Here are some pics.. Do you think my solder points are broken?
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
I went to autozone and picked up a soldering iron for $8 and thought I could do this myself since it looked easy enough. I have never soldered anything before.. This is the outcome...😩😤😭 ..... My car is still dead... HELP !!!
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Looks like you're not getting hot enough. Lay the iron on the base of the pins until all the old solder liquefies then add some new to the pins.
Or send it to DJ for $20 he will fix it.
Or get a new one from rock auto for $145.
Or send it to DJ for $20 he will fix it.
Or get a new one from rock auto for $145.
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Sure hope he used rosin-core solder, as it MIGHT be salvageable. Your not letting the iron get hot enough, which in turn isn't getting the places you wish to 'reflow' hot enough. Then there is the problem of getting it TOO hot. There is a fine line, hot enough AND not too hot. Times like these, you should not be 'practicing' on your RCM module. After you either send it to DJ (or) buy a replacement, you should then leave soldering to someone else until you can flow the solder properly.
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Sure hope he used rosin-core solder, as it MIGHT be salvageable. Your not letting the iron get hot enough, which in turn isn't getting the places you wish to 'reflow' hot enough. Then there is the problem of getting it TOO hot. There is a fine line, hot enough AND not too hot. Times like these, you should not be 'practicing' on your RCM module. After you either send it to DJ (or) buy a replacement, you should then leave soldering to someone else until you can flow the solder properly.
Who's dj???? The guy that posted this thread? If so I did already message him 2 days ago. No response yet 😐
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
"Send an email with your address to:
tighed1@hotmail.com"
It will take a week or two to get it shipped, repaired, and returned anyway.
If you need instant service, I suggest you buy a new one online and ship it next day air.
Last edited by GregWork; 05-03-2015 at 04:51 PM.
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
The boards were soldered in a bath of molten solder and the temperature of the pins was too cold as a result the solder did not bond properly to the pins. This is known as a cold joint.
As time and usage progress the joint weakens even more until arcing makes it fail completely.
The solder needs to be removed as much as possible from the joint, the pins cleaned to bare metal, and re soldered with rosin cored solder only, do not use acid cored solder.
This problem was written about before the Crossfire hit the market on the MB forums.
The seat relay was known to suffer from the same problem.
As time and usage progress the joint weakens even more until arcing makes it fail completely.
The solder needs to be removed as much as possible from the joint, the pins cleaned to bare metal, and re soldered with rosin cored solder only, do not use acid cored solder.
This problem was written about before the Crossfire hit the market on the MB forums.
The seat relay was known to suffer from the same problem.
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
https://www.youtube.com/watch?featur...JxytERvg#t=146
This video should start at the 2:25 mark.
Simular workflow except in our case the pins are bigger and there is already solder there, we just need to heat it till it flows back around the pin while adding a little more solder.
Last edited by KDW4Him; 05-03-2015 at 10:40 PM.
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
SLK230 MB#545 02 05
SLK320, SLK32 & Crossfire MB#545 03 05
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
If you look at the actual parts then you can see that the CF RCM uses theg larger fuse, at least in the ones I have seen.
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
I think you have misunderstood me, forget it as it is too hard to go through it all and straighten it out.