How to Repair Relay Control Module (RCM) - (Mystery no Start)
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Bill,
Visiting grandkids took priority, but I did trap the rat so that damage will stop. Female Eastern Woodrat, best I could tell. No evidence of nest or others.
Will know more shortly, and will post anything I find.
Michael
Visiting grandkids took priority, but I did trap the rat so that damage will stop. Female Eastern Woodrat, best I could tell. No evidence of nest or others.
Will know more shortly, and will post anything I find.
Michael
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
The battery was new when I bought the car about five years ago. I have had it turn over slowly, but it did fine on the trip to KY two weeks ago. From what I could understand in the FSM, it can have enough fire for everything but start, but will not attempt to start if the voltage is too low to satisfy one of the control modules. That does match my car, what you describe, and also the bad board. I'll be checking both.
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
KDW,
Thanks for the reminder. I had forgotten how many have had strange problems from a slightly off battery. I'll check voltage and voltage drop first, then probably resolder the RCM joints even if they look good. With any remaining trouble, I'll replace the battery. I really don't want to dig into wiring looking for rodent damage that's not there, and maybe do some new damage in the process.
Will post results.
Michael
Thanks for the reminder. I had forgotten how many have had strange problems from a slightly off battery. I'll check voltage and voltage drop first, then probably resolder the RCM joints even if they look good. With any remaining trouble, I'll replace the battery. I really don't want to dig into wiring looking for rodent damage that's not there, and maybe do some new damage in the process.
Will post results.
Michael
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
~ Bill
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Bill,
Not a lot to report, but I did get a chance late afternoon to check voltage. With a decent meter, I had 12.35v, with a drop to about 12.20v with the key on, or with lights on. I couldn't notice an additional drop when the key went to "start," but didn't work hard at it. I have in on a slow charge and will check again tomorrow afternoon. I think I should have gotten closer to 13.5v with a good fully charged battery.
Will still check and probably resolder the RCM joints as this thread instructs.
More to follow.
Michael
Not a lot to report, but I did get a chance late afternoon to check voltage. With a decent meter, I had 12.35v, with a drop to about 12.20v with the key on, or with lights on. I couldn't notice an additional drop when the key went to "start," but didn't work hard at it. I have in on a slow charge and will check again tomorrow afternoon. I think I should have gotten closer to 13.5v with a good fully charged battery.
Will still check and probably resolder the RCM joints as this thread instructs.
More to follow.
Michael
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
I finally got a chance to pull the RCM. Under good magnification, two connections were very bad, and remainder were questionable. I remade those as instructed, reinstalled, and got - nothing. Battery voltage after sitting about 48 hours had dropped from about 13.3 to about 12.8.
I will replace the battery.
Other data points - no error messages, but I do get the check engine light. That seems expected since the key is on and the engine is not. The one odd one - temp is negative 36 F. It's nearly July in Mississippi.
I spent more time with a flashlight in engine bay, trunk, and dug under carpet and I still find no damaged wires, and no wiring insulation confetti.
Any solid input on what I can and cannot do with an OBDII reader would be very welcome. It's over an hour by trailer to the nearest dealer who will have the OBDIII device for this car.
More to follow. Don't look for it in the "for sales" yet!
Michael
I will replace the battery.
Other data points - no error messages, but I do get the check engine light. That seems expected since the key is on and the engine is not. The one odd one - temp is negative 36 F. It's nearly July in Mississippi.
I spent more time with a flashlight in engine bay, trunk, and dug under carpet and I still find no damaged wires, and no wiring insulation confetti.
Any solid input on what I can and cannot do with an OBDII reader would be very welcome. It's over an hour by trailer to the nearest dealer who will have the OBDIII device for this car.
More to follow. Don't look for it in the "for sales" yet!
Michael
Join Date: Jan 2011
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Now the car is closer to for sale, or free, or donation to the fire department for training purposes.
Repaired RCM. Not my first time with a soldering station.
New battery.
Not a sound. No hint of additional drain in the start position.
No warning or error message on instrument cluster.
Still shows -36F
How delicate is the starter? Last trip was in monsoon rains, enough to get me loose on the road several times at low speed. Car did nothing strange at the time. That was a month ago.
Any other suggestions will be appreciated.
Michael
Repaired RCM. Not my first time with a soldering station.
New battery.
Not a sound. No hint of additional drain in the start position.
No warning or error message on instrument cluster.
Still shows -36F
How delicate is the starter? Last trip was in monsoon rains, enough to get me loose on the road several times at low speed. Car did nothing strange at the time. That was a month ago.
Any other suggestions will be appreciated.
Michael
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
That temp display is most likely a loose connection to the temp probe mounted in the driver side lower grill.
I don't however think that would cause the symptoms described.
If you are really ready to pull your hair out, trailer it over here and I'll do what I can to help you.
We can pluck known good things off my car and try them, or we can troubleshoot with meters etc.
I don't however think that would cause the symptoms described.
If you are really ready to pull your hair out, trailer it over here and I'll do what I can to help you.
We can pluck known good things off my car and try them, or we can troubleshoot with meters etc.
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
I'll get it up on jack stands and check the temp probe and wiring underneath, as well as the starter. This would have been better done in April at 70 degrees.
It may end up on a trailer toward you. I appreciate the offer, and am not very confident on the electrical side. I should probably invest now in a good OBDII tool, but will need to do some looking. No idea what type or level of tool is good and still a reasonable investment.
Hair is pretty much gone already. I'd be close if the remainder were long enough.
Again, thank you.
Michael
It may end up on a trailer toward you. I appreciate the offer, and am not very confident on the electrical side. I should probably invest now in a good OBDII tool, but will need to do some looking. No idea what type or level of tool is good and still a reasonable investment.
Hair is pretty much gone already. I'd be close if the remainder were long enough.
Again, thank you.
Michael
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
I'll get it up on jack stands and check the temp probe and wiring underneath, as well as the starter. This would have been better done in April at 70 degrees.
It may end up on a trailer toward you. I appreciate the offer, and am not very confident on the electrical side. I should probably invest now in a good OBDII tool, but will need to do some looking. No idea what type or level of tool is good and still a reasonable investment.
Hair is pretty much gone already. I'd be close if the remainder were long enough.
Again, thank you.
Michael
It may end up on a trailer toward you. I appreciate the offer, and am not very confident on the electrical side. I should probably invest now in a good OBDII tool, but will need to do some looking. No idea what type or level of tool is good and still a reasonable investment.
Hair is pretty much gone already. I'd be close if the remainder were long enough.
Again, thank you.
Michael
( only used on hot days when I am in there working )
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
I finally got a chance to pull the RCM. Under good magnification, two connections were very bad, and remainder were questionable. I remade those as instructed, reinstalled, and got - nothing. Battery voltage after sitting about 48 hours had dropped from about 13.3 to about 12.8.
I will replace the battery.
Other data points - no error messages, but I do get the check engine light. That seems expected since the key is on and the engine is not. The one odd one - temp is negative 36 F. It's nearly July in Mississippi.
I spent more time with a flashlight in engine bay, trunk, and dug under carpet and I still find no damaged wires, and no wiring insulation confetti.
Any solid input on what I can and cannot do with an OBDII reader would be very welcome. It's over an hour by trailer to the nearest dealer who will have the OBDIII device for this car.
More to follow. Don't look for it in the "for sales" yet!
Michael
I will replace the battery.
Other data points - no error messages, but I do get the check engine light. That seems expected since the key is on and the engine is not. The one odd one - temp is negative 36 F. It's nearly July in Mississippi.
I spent more time with a flashlight in engine bay, trunk, and dug under carpet and I still find no damaged wires, and no wiring insulation confetti.
Any solid input on what I can and cannot do with an OBDII reader would be very welcome. It's over an hour by trailer to the nearest dealer who will have the OBDIII device for this car.
More to follow. Don't look for it in the "for sales" yet!
Michael
Join Date: Jan 2011
Location: northern Mississippi
Age: 67
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Bill,
I'm about 12 miles from civilization, but any distance requires a trailer at this point.
Part of my being willing to buy a scanner is my hope to do a little work on modern cars for income. I just finished a four semester auto body repair course at a local community college (Navy retirement gives you choices but doesn't make you rich). I did well, and love it. The newer cars are portable computers powered by a gasoline engine. I'm lost there. I will start again in August, in one or two semesters of primarily automotive electrical systems. The scanner will be helpful then and probably into the future.
I don't have a feel for how much the Crossfire will tell us without the special ODBIII equipment that is Chrysler-only, but still hope to avoid a trip into Memphis pulling a trailer.
And thanks for your service, shipmate!
Michael
I'm about 12 miles from civilization, but any distance requires a trailer at this point.
Part of my being willing to buy a scanner is my hope to do a little work on modern cars for income. I just finished a four semester auto body repair course at a local community college (Navy retirement gives you choices but doesn't make you rich). I did well, and love it. The newer cars are portable computers powered by a gasoline engine. I'm lost there. I will start again in August, in one or two semesters of primarily automotive electrical systems. The scanner will be helpful then and probably into the future.
I don't have a feel for how much the Crossfire will tell us without the special ODBIII equipment that is Chrysler-only, but still hope to avoid a trip into Memphis pulling a trailer.
And thanks for your service, shipmate!
Michael
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
On this RCM fix...do I want to completely melt away the old solder or just add new solder on top of the old? Do I heat the pins on the board to draw in new solder or just heat the solder and let it drip onto the contacts? Is resin core solder the same as rosin core solder? Sorry for all these questions...I' m just ' detail' type of person. Thanks in advance for any info on this.
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
A Star-DAS scanner like MB and originally supplied to Chrysler is not cheap, we're talking $1500 off eBay for one that might well be questionable.
At the other end of the scale, a simple code reader for reading and resetting codes is about $12 on eBay, but not much good for diagnostics.
Some members have the Star-DAS, but I seriously doubt they would loan it out.
At the other end of the scale, a simple code reader for reading and resetting codes is about $12 on eBay, but not much good for diagnostics.
Some members have the Star-DAS, but I seriously doubt they would loan it out.
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
On this RCM fix...do I want to completely melt away the old solder or just add new solder on top of the old? Do I heat the pins on the board to draw in new solder or just heat the solder and let it drip onto the contacts? Is resin core solder the same as rosin core solder? Sorry for all these questions...I' m just ' detail' type of person. Thanks in advance for any info on this.
Proper soldering technique is to heat both components equally to a point where they will melt the solder applied to them. You are looking for a nice shiny finish when done.
Do NOT "drip" solder onto them.
Yes, resin and rosin are the same, do NOT use acid core solder ( meant for plumbing purposes )
The joints require quite a bit of heat, a soldering GUN is better that a soldering PENCIL here.
http://d2pbmlo3fglvvr.cloudfront.net...5VZZ2_AS01.JPG
Last edited by ala_xfire; 06-25-2015 at 02:51 PM.
Join Date: Jan 2011
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Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
copied until I learn to quote:
Ala_xfire said:
A Star-DAS scanner like MB and originally supplied to Chrysler is not cheap, we're talking $1500 off eBay for one that might well be questionable.
At the other end of the scale, a simple code reader for reading and resetting codes is about $12 on eBay, but not much good for diagnostics.
Some members have the Star-DAS, but I seriously doubt they would loan it out.
I am hoping I can get something in between that would help with most, but still not cost more than I'll ever see in return. There seem to be several in the $75 - 200 range. Any recommendations?
Thanks,
Michael
Ala_xfire said:
A Star-DAS scanner like MB and originally supplied to Chrysler is not cheap, we're talking $1500 off eBay for one that might well be questionable.
At the other end of the scale, a simple code reader for reading and resetting codes is about $12 on eBay, but not much good for diagnostics.
Some members have the Star-DAS, but I seriously doubt they would loan it out.
I am hoping I can get something in between that would help with most, but still not cost more than I'll ever see in return. There seem to be several in the $75 - 200 range. Any recommendations?
Thanks,
Michael
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Here's the Weller on Amazon for $41.36 with free shipping :
( I've had mine since I was 13 years old, I'm 71 now. )
( I've had mine since I was 13 years old, I'm 71 now. )
Re: How to Repair Relay Control Module (RCM) - (Mystery no Start)
Here's the Weller on Amazon for $41.36 with free shipping :
Weller 8200 Universal Soldering Gun - Souldering Gun - Amazon.com
( I've had mine since I was 13 years old, I'm 71 now. )
Weller 8200 Universal Soldering Gun - Souldering Gun - Amazon.com
( I've had mine since I was 13 years old, I'm 71 now. )
Mine is a 8200 PK that I got in 1972 it cost $8, still in the carry case with the bill, a new spare tip and instructions.
Last edited by onehundred80; 06-25-2015 at 05:07 PM.