How to Repair Relay Control Module (RCM) - (Mystery no Start)
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
[quote=solnyc2]thank you very much.[/quote]
There is a thread that is attempting to build up a list of the Chrysler parts and the equivalent Mercedes numbers.
The RCM is on it.
https://www.crossfireforum.org/forum...tml#post427253
There is a thread that is attempting to build up a list of the Chrysler parts and the equivalent Mercedes numbers.
The RCM is on it.
https://www.crossfireforum.org/forum...tml#post427253
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
I don't think all PCB connections are done by machine. The boards are certainly done on a wave solder machine, but the component connections, as far as I know, are still very often done by hand.
In this case though, with the bad connections always in the same spot, I could see that being an issue with an automated process. If people were involved, it would likely be more than one person adding those particular components, so you'd see more variety in the look of the finished solder joints.
In this case though, with the bad connections always in the same spot, I could see that being an issue with an automated process. If people were involved, it would likely be more than one person adding those particular components, so you'd see more variety in the look of the finished solder joints.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by Joliet John
I don't think all PCB connections are done by machine. The boards are certainly done on a wave solder machine, but the component connections, as far as I know, are still very often done by hand.
In this case though, with the bad connections always in the same spot, I could see that being an issue with an automated process. If people were involved, it would likely be more than one person adding those particular components, so you'd see more variety in the look of the finished solder joints.
In this case though, with the bad connections always in the same spot, I could see that being an issue with an automated process. If people were involved, it would likely be more than one person adding those particular components, so you'd see more variety in the look of the finished solder joints.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by onehundred80
Could it be something to do with the material being soldered, when I re-soldered my one I got the distinct feeling that the material being soldered was not copper, it felt like steel and steel is notorious for soldering.
If that's the case, they'd be better off to use a solder with a lower melt temp in that area.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
tighed1, thanks for all the valuable information on the "Mystery No Start" problem. I recently developed this problem on my 2005 Crossfire Coupe. The problem turned out to be "Cold Solder Joints" in the same area you described. In fact, if you number the connections from the Printed Circuit Board, PCB, edge as number 6, 5, 4, 3, 2, and 1, I had "Cold Solder Joint" on connections 1, 2 and 3. I didn't verify them by continuity testing them. I just visually identified them as Defective (Cold Solder Joints) . I added a small amount of Soldering Paste Flux and re-soldered all SIX connections using some multi-core solder. Your pix and information were invaluable in correcting the problem. Thanks again for all the valuable information you provided
Regards
Tom Fineran
Regards
Tom Fineran
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by solnyc2
Hi Folks,
Where can you buy a new RCM?
Is there a Mercedes equivalent?
Any advice would be greatly appreciated.
Where can you buy a new RCM?
Is there a Mercedes equivalent?
Any advice would be greatly appreciated.
Regards
Tom Fineran
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by tfineran
tighed1, thanks for all the valuable information on the "Mystery No Start" problem. I recently developed this problem on my 2005 Crossfire Coupe. The problem turned out to be "Cold Solder Joints" in the same area you described. In fact, if you number the connections from the Printed Circuit Board, PCB, edge as number 6, 5, 4, 3, 2, and 1, I had "Cold Solder Joint" on connections 1, 2 and 3. I didn't verify them by continuity testing them. I just visually identified them as Defective (Cold Solder Joints) . I added a small amount of Soldering Paste Flux and re-soldered all SIX connections using some multi-core solder. Your pix and information were invaluable in correcting the problem. Thanks again for all the valuable information you provided
Regards
Tom Fineran
Regards
Tom Fineran
The use of the more common acid cored solder and acid flux is not recommended at all because the acid will corrode the joint if it is not removed completely.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by onehundred80
When soldering electrical components rosin cored solder and rosin flux must be used.
The use of the more common acid cored solder and acid flux is not recommended at all because the acid will corrode the joint if it is not removed completely.
The use of the more common acid cored solder and acid flux is not recommended at all because the acid will corrode the joint if it is not removed completely.
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Solder using the Hot End.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by tfineran
Your comments seem to be directed at Novices. So you might add things like:
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Solder using the Hot End.
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Solder using the Hot End.
I see no reason not to emphasise the use of the proper materials.
Just for you I have amended your instructions.
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Stick the Hot End where the sun does not shine.
Last edited by onehundred80; 10-22-2010 at 05:46 PM.
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re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by tfineran
Your comments seem to be directed at Novices. So you might add things like:
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Solder using the Hot End.
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Solder using the Hot End.
You have made a lousy three posts here and have ASSumed way too much. This is a group of friends here and we try to help one another avoid mistakes when ever possible.
NOW...
I've been repairing electronics to the component-level for 29 years and I sure don't need anyone telling me how to solder, 100-80 included.
HOWEVER...
We have a lot of people who show up here and try (with our help) to do things they have never done before. 100-80's post was, IMO, appropriate. In fact, as is so often the case, I would say that he "beat me to it".
This board is full of "novices". Hell, I'd never clay barred a car until a month ago - no way I'd have drug a piece of "clay" across the finish of my car without advice from people here!
Last edited by pizzaguy; 10-22-2010 at 07:07 PM.
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re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by tfineran
Your comments seem to be directed at Novices. So you might add things like:
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Solder using the Hot End.
1. Plug the Soldering Iron into a working outlet.
2. Hold the Soldering Iron by the Cool End.
3. Solder using the Hot End.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Thanks pizzaguy and Larry, sometimes what is written in these posts is all true but a small crucial point that is assumed by the writer may not be obvious to some readers.
I have learned a lot on this forum and I am always willing to help if I can. I always try to add a lot of info in my posts and some who know more think I am adding too much info. Too much for them maybe but maybe not enough for someone who knows little about the subject.
I like this site because you can learn a lot about the car, I read the SRT-6 and roadster posts that have no bearing on the coupe but its all info to learn and some small item in it may be of some future use.
The terminals that have to be re soldered appear to be steel, mine were black and I tried to file them to clean them up prior to soldering.
Pizzaguy, have you come across steel terminals like this before?
I have learned a lot on this forum and I am always willing to help if I can. I always try to add a lot of info in my posts and some who know more think I am adding too much info. Too much for them maybe but maybe not enough for someone who knows little about the subject.
I like this site because you can learn a lot about the car, I read the SRT-6 and roadster posts that have no bearing on the coupe but its all info to learn and some small item in it may be of some future use.
The terminals that have to be re soldered appear to be steel, mine were black and I tried to file them to clean them up prior to soldering.
Pizzaguy, have you come across steel terminals like this before?
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re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by onehundred80
Thanks pizzaguy and Larry,
Anytime.
Pizzaguy, have you come across steel terminals like this before?
They are similar to the eyelets in the old (1960's) Motorola Motrac circuit boards. Those damn things, if corroded by not being covered with solder at the factory, had to be sanded/filed down in order to make solder flow over them well.
VERY aggravating.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by tfineran
2. Hold the Soldering Iron by the Cool End.
re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Originally Posted by onehundred80
When soldering electrical components rosin cored solder and rosin flux must be used.
The use of the more common acid cored solder and acid flux is not recommended at all because the acid will corrode the joint if it is not removed completely.
The use of the more common acid cored solder and acid flux is not recommended at all because the acid will corrode the joint if it is not removed completely.