Electrically conductive grease?
Discussion
Chaps,
Have a bit of an ongoing issue with her Volvo and slowly trying to rule out options and I've narrowed it to one of the several multiplugs at the CEM (fuseboard) and it's been suggested that having cleaned all the pins and terminals with a cocktail of fine emery paper, contact cleaner, a soft toothbrush and compressed air... that I use electrically conductive grease (in moderation) on the pins just to help eliminate any issues.
However, bit confused by which conductive grease is suitable for such applications - it's not to keep moisture out so not Vaseline but it's to be conductive thus I think the correct term is diuretic grease of which there are many many options ranging form £1.50 for a small tube to about £20 (eBay) so I'm not sure if a) it's even worth the hassle and b) if there's any that are "better" than others?
Any pointers and /or recommendations?
Cheers
Have a bit of an ongoing issue with her Volvo and slowly trying to rule out options and I've narrowed it to one of the several multiplugs at the CEM (fuseboard) and it's been suggested that having cleaned all the pins and terminals with a cocktail of fine emery paper, contact cleaner, a soft toothbrush and compressed air... that I use electrically conductive grease (in moderation) on the pins just to help eliminate any issues.
However, bit confused by which conductive grease is suitable for such applications - it's not to keep moisture out so not Vaseline but it's to be conductive thus I think the correct term is diuretic grease of which there are many many options ranging form £1.50 for a small tube to about £20 (eBay) so I'm not sure if a) it's even worth the hassle and b) if there's any that are "better" than others?
Any pointers and /or recommendations?
Cheers
Thanks.
When I first cleaned the pins and terminals, I put a light smear of Vaseline on the pins in a bid to keep moisture / corrosion at bay however latterly I've had it all stripped out and today, had the CEM completely apart and despite what others say, I'm 100% confident my issues are not moisture related as my unit is dry and there's no evidence of corrosion.
Granted, that leaves me on a needle in a haystack hunt to now try and find the source of an electrical meltdown that happen once in a blue moon, with no pattern to it however it's either a faulty CEM unit (though most its due to corrosion) or it's a pin connection issue but I've today cleaned every pin and I've put a small piece of duct tape on the side of the multiplugs in order to create a tighter fitting interface between plug and unit (working on the basis, any movement may be breaking the contacts) but that's when conductive grease was suggested.
Very frustrating fault, more so as it's only happened once with me but several times with her and she's not lost all faith in the car. More frustrating is that as soon as it does it, simply unplugging the plugs and reconnecting them cures it completely for another day / week / month but in doing so, the fault goes away thus it's impossible to diagnose. It broke down earlier, unplugged, plugged in and it's perfect again and might be fixed... or might do it again whenever or wherever it feels like it.
But I digress....
When I first cleaned the pins and terminals, I put a light smear of Vaseline on the pins in a bid to keep moisture / corrosion at bay however latterly I've had it all stripped out and today, had the CEM completely apart and despite what others say, I'm 100% confident my issues are not moisture related as my unit is dry and there's no evidence of corrosion.
Granted, that leaves me on a needle in a haystack hunt to now try and find the source of an electrical meltdown that happen once in a blue moon, with no pattern to it however it's either a faulty CEM unit (though most its due to corrosion) or it's a pin connection issue but I've today cleaned every pin and I've put a small piece of duct tape on the side of the multiplugs in order to create a tighter fitting interface between plug and unit (working on the basis, any movement may be breaking the contacts) but that's when conductive grease was suggested.
Very frustrating fault, more so as it's only happened once with me but several times with her and she's not lost all faith in the car. More frustrating is that as soon as it does it, simply unplugging the plugs and reconnecting them cures it completely for another day / week / month but in doing so, the fault goes away thus it's impossible to diagnose. It broke down earlier, unplugged, plugged in and it's perfect again and might be fixed... or might do it again whenever or wherever it feels like it.
But I digress....
Deep breath...
"
The issue:
I have a 2007 V50 2.0 Sport that I've owned coming on for 2 years now and it's a fabulous thing that I love and despite its 218,000 miles it's behaving (largely) very well however about 6 months in to ownership, out of the blue one day it had an electrical meltdown with her ladyship at the wheel.
Loss of power
Wipers running themselves
Brake failure - Stop immediately warning
ABS / DSTC light on
Radio / heater panel erratic
Now, I was aware of the S40 / V50 CEM related problems and knew that Volvo's stance was to simply replace all of the above, reprogramme it and job's a good un however I also knew that the pins / multi-plugs could cause issues and cleaning them usually works.
So, I unplugged all the plugs and removed the CEM and carefully cleaned the pins with electrical contact cleaner and then sprayed the multi-plugs and all was well, issues resolved and the car drove perfectly for weeks, maybe even months and peace was restored to the household.
Spoke too soon...
Around last November, it happened again... exact same symptoms and turning the car on and off didn't change anything. Wife en route to an interview... temper lost. At the roadside I unplugged the multi-plugs, plugged them back in and away it went again, driving perfectly and did so for another few weeks... then did it again. But again, unplug, plug in and away it went again.
So, by this stage I'd started looking into the many many posts on the subject and they all seemed to end with "clean the pins" and that was it, problem solved but I wasn't sure on that one as the pins on mine were clean, free from corrosion and wiggling, poking and prodding when the car was running has no ill effect on matters. It was and still is, a completely sporadic issue. I did happen across a thread where a chap seemed to think that one of the snap lock clamps was worn and thus wasn't holding the corresponding plug tightly in place so I checked all of mine and all seemed well.
Still with me...?
Before Christmas, it happened again and like the previous times there was no common reason... it didn't seem to matter of it was hot, cold, wet or dry and nor could I see any reasons for it doing what it did though Googling seemed to hint at leaking windscreens or dodgy sunroof drains being a prime suspect in introducing moisture in to the car and thus, in to the CEM itself but I was pretty confident mine wasn't suffering from any moisture and kicked, nudging and shaking the CEM whilst in motion did nothing thus I ruled out an errant handbag or bottle of wine rolling around the footwell.
The last time it happened, I didn't unplug all the multi-plugs but instead ONLY unplugged the tow smaller ones (green and brown) on the base of the unit and plugged them in. Again, issue resolved which made me wonder if I'd started to home in on the culprit. I again painstakingly cleaned the terminal and pins and added a thin strip of cloth tape to the sides of the multi-plugs to try and ensure there were very snug in their place in the CEM and then put a strip of duct tape over the top to hold both plugs tightly in.
Problem solved...
Or so I thought as it ran fine for the past 6 weeks / 2,000 miles however yesterday it did it again en route to my wife's work and having somehow manged to get it there, she called at 5pm to say the car would not start. It was "dead" and so she'd had enough and got a lift. Part of me hoped it was dead as fault finding may have just got a bit easier.
Alas, I was wrong and today I went to collect it and whilst the doors unlocked, the dash fired in to life and the key slot "clicked" to accept the key... there was nothing. Key out, back in and it started first turn and did so for several repeated attempts. No lights on the dash, no warnings, no mad wipers. I left it and returned an hour or so later and it started first turn however immediately went into meltdown without even being moved. Again, unplugged the small green plug, re-plugged and away it went happily.
There lies the issue... every time I remove the plugs and reconnect, it's fixed and it'll run flawlessly for however long it likes then without warning, will have a meltdown... or perhaps it won't now but the issue being, she's lost all faith and wants rid of it. And probably me as I'm still fighting its case much to her disgust and I can see why she's unhappy, toddler in the car, lone female... rural living and an issue that seems impossible to trace.
My options...
Well, that's the reason for this post as hypothetically it may be fixed now but the chances are I'll be back soon to say "Guess what, done it again" and so having put it out there, I'd be keen for any advice / words of wisdom / previous victims and more so, if anybody found a solution.
I know that used CEM's have to be coded to work, though there seems to be a debate over whether used CEM's can be re-coded for the immobilser and such like - any ideas?
Volvo Diagnostics do a refurbished CEM for £260.00 which is plug and play, thus I assume your old one goes off to them first to be cloned over and whilst that seems the best option and I've a very high opinion of their work (they did a DEM on a V70R for me) the issue is... I'm honestly not convinced it's the CEM itself to blame.
Volvo do a replacement pin set for the multi-plugs but they thought of trying to re-pin eight multi-plugs does not inspire me plus I'm reliably informed, it's rather costly too plus part of me thinks how would that resolve the issue... issue possibly being a poor connection but you'd expect some sort of glitch as the wires were pulled about with the car running, but there's not.
Finally, somebody suggested electrically conductive grease but again the jury is out as to how effective it would be but anything is worth trying I guess.
Sell it, buy her a VW Up! GTi...
Yes, that'd be a solution but I'm now so ****ed with this and the fact that I'm unable to hone in on the source of the issues, that I want to see it through. For such a common issue, there's very little in the way of resolution... I mean is there a common issue or does this sound unique given I've done the usual tried and tested suggestions and yet the fault keeps recurring.
Open to any and all suggestions and happy to discuss this further / share my findings moving forwards..."
One of those "needle in a haystack" kind of fault finding missions made harder by the fact the needle only appears once in a blue moon and for a matter of seconds.
Cheers
"
The issue:
I have a 2007 V50 2.0 Sport that I've owned coming on for 2 years now and it's a fabulous thing that I love and despite its 218,000 miles it's behaving (largely) very well however about 6 months in to ownership, out of the blue one day it had an electrical meltdown with her ladyship at the wheel.
Loss of power
Wipers running themselves
Brake failure - Stop immediately warning
ABS / DSTC light on
Radio / heater panel erratic
Now, I was aware of the S40 / V50 CEM related problems and knew that Volvo's stance was to simply replace all of the above, reprogramme it and job's a good un however I also knew that the pins / multi-plugs could cause issues and cleaning them usually works.
So, I unplugged all the plugs and removed the CEM and carefully cleaned the pins with electrical contact cleaner and then sprayed the multi-plugs and all was well, issues resolved and the car drove perfectly for weeks, maybe even months and peace was restored to the household.
Spoke too soon...
Around last November, it happened again... exact same symptoms and turning the car on and off didn't change anything. Wife en route to an interview... temper lost. At the roadside I unplugged the multi-plugs, plugged them back in and away it went again, driving perfectly and did so for another few weeks... then did it again. But again, unplug, plug in and away it went again.
So, by this stage I'd started looking into the many many posts on the subject and they all seemed to end with "clean the pins" and that was it, problem solved but I wasn't sure on that one as the pins on mine were clean, free from corrosion and wiggling, poking and prodding when the car was running has no ill effect on matters. It was and still is, a completely sporadic issue. I did happen across a thread where a chap seemed to think that one of the snap lock clamps was worn and thus wasn't holding the corresponding plug tightly in place so I checked all of mine and all seemed well.
Still with me...?
Before Christmas, it happened again and like the previous times there was no common reason... it didn't seem to matter of it was hot, cold, wet or dry and nor could I see any reasons for it doing what it did though Googling seemed to hint at leaking windscreens or dodgy sunroof drains being a prime suspect in introducing moisture in to the car and thus, in to the CEM itself but I was pretty confident mine wasn't suffering from any moisture and kicked, nudging and shaking the CEM whilst in motion did nothing thus I ruled out an errant handbag or bottle of wine rolling around the footwell.
The last time it happened, I didn't unplug all the multi-plugs but instead ONLY unplugged the tow smaller ones (green and brown) on the base of the unit and plugged them in. Again, issue resolved which made me wonder if I'd started to home in on the culprit. I again painstakingly cleaned the terminal and pins and added a thin strip of cloth tape to the sides of the multi-plugs to try and ensure there were very snug in their place in the CEM and then put a strip of duct tape over the top to hold both plugs tightly in.
Problem solved...
Or so I thought as it ran fine for the past 6 weeks / 2,000 miles however yesterday it did it again en route to my wife's work and having somehow manged to get it there, she called at 5pm to say the car would not start. It was "dead" and so she'd had enough and got a lift. Part of me hoped it was dead as fault finding may have just got a bit easier.
Alas, I was wrong and today I went to collect it and whilst the doors unlocked, the dash fired in to life and the key slot "clicked" to accept the key... there was nothing. Key out, back in and it started first turn and did so for several repeated attempts. No lights on the dash, no warnings, no mad wipers. I left it and returned an hour or so later and it started first turn however immediately went into meltdown without even being moved. Again, unplugged the small green plug, re-plugged and away it went happily.
- ** got serious...
There lies the issue... every time I remove the plugs and reconnect, it's fixed and it'll run flawlessly for however long it likes then without warning, will have a meltdown... or perhaps it won't now but the issue being, she's lost all faith and wants rid of it. And probably me as I'm still fighting its case much to her disgust and I can see why she's unhappy, toddler in the car, lone female... rural living and an issue that seems impossible to trace.
My options...
Well, that's the reason for this post as hypothetically it may be fixed now but the chances are I'll be back soon to say "Guess what, done it again" and so having put it out there, I'd be keen for any advice / words of wisdom / previous victims and more so, if anybody found a solution.
I know that used CEM's have to be coded to work, though there seems to be a debate over whether used CEM's can be re-coded for the immobilser and such like - any ideas?
Volvo Diagnostics do a refurbished CEM for £260.00 which is plug and play, thus I assume your old one goes off to them first to be cloned over and whilst that seems the best option and I've a very high opinion of their work (they did a DEM on a V70R for me) the issue is... I'm honestly not convinced it's the CEM itself to blame.
Volvo do a replacement pin set for the multi-plugs but they thought of trying to re-pin eight multi-plugs does not inspire me plus I'm reliably informed, it's rather costly too plus part of me thinks how would that resolve the issue... issue possibly being a poor connection but you'd expect some sort of glitch as the wires were pulled about with the car running, but there's not.
Finally, somebody suggested electrically conductive grease but again the jury is out as to how effective it would be but anything is worth trying I guess.
Sell it, buy her a VW Up! GTi...
Yes, that'd be a solution but I'm now so ****ed with this and the fact that I'm unable to hone in on the source of the issues, that I want to see it through. For such a common issue, there's very little in the way of resolution... I mean is there a common issue or does this sound unique given I've done the usual tried and tested suggestions and yet the fault keeps recurring.
Open to any and all suggestions and happy to discuss this further / share my findings moving forwards..."
One of those "needle in a haystack" kind of fault finding missions made harder by the fact the needle only appears once in a blue moon and for a matter of seconds.
Cheers
This is a tough one to describe but I had an intermittant electrical problem I found purely by luck when I had a multimeter on somewhere by mistake when disturbing other stuff.
Turned out the female pins in the female plug had lost their tightness (oh er) and would sometimes lose contact with the male pin. Had to strip the plug, bend in the female pin receptacles and create a much tighter fit on the male pins.
Reason I thought it may be your issue is you are asking for a way of increasing conductivity across the plug contacts.
Hope that helps.
Turned out the female pins in the female plug had lost their tightness (oh er) and would sometimes lose contact with the male pin. Had to strip the plug, bend in the female pin receptacles and create a much tighter fit on the male pins.
Reason I thought it may be your issue is you are asking for a way of increasing conductivity across the plug contacts.
Hope that helps.
Uggers said:
Turned out the female pins in the female plug had lost their tightness (oh er) and would sometimes lose contact with the male pin. Had to strip the plug, bend in the female pin receptacles and create a much tighter fit on the male pins.
^^^^Wot 'e said.This is your answer rather than dielectric grease, (I think you meant) as even if it did what you think, it would also possibly create a short/partial short to an adjacent pin & create real mayhem.
Do not use conductive grease!
As you said that you can’t replicate the fault by wiggling the cables I’d be inclined to look elsewhere
Personally I’d suspect a dry joint within the unit. Take it apart and resolder every connector pin, relay pin fuse contact etc. Anything soldered to the pcb that has a bit of thermal mass (ie the bigger bits) may not have been flow soldered well at the time. Add age, vibration and thermal cycling and it’s very common for larger soldered joints to fail.
As you said that you can’t replicate the fault by wiggling the cables I’d be inclined to look elsewhere
Personally I’d suspect a dry joint within the unit. Take it apart and resolder every connector pin, relay pin fuse contact etc. Anything soldered to the pcb that has a bit of thermal mass (ie the bigger bits) may not have been flow soldered well at the time. Add age, vibration and thermal cycling and it’s very common for larger soldered joints to fail.
Ahh, now that's a useful bit of information (as is all that's been posted) so will have a look at that shortly... although, if it was an earth issue, would that correspond to the fact it clears as soon as the lower multiplugs on the CEM are removed and refitted. Likewise, removing them with the car running gives the exact same series of symptoms hence I'm finding myself drawn to that area and wondering if there's a poor connection somewhere in those too plugs.
Granted, it's behaving fine having been removed yesterday but that's the issue. It'll run fine for any given period of time, then have a meltdown but as soon as you move the plugs, it clears and it's fine for weeks again. However, poking, prodding and wiggling the plugs and wires doesn't seem to effect it in any way which does slightly contradict a poor connection theory as you'd expect some sort of hiccup. Or indeed, having been removed and cleaned several times, any dirty connection would be resolved.
I'll pass on the electrical grease, granted the pins and terminals should be spotlessly clean and free from any contaminants following yesterdays total strip down of the CEM itself and granted, it may have actually cured the problem but I won't know that until it does it again... or doesn't and that could take weeks / months to happen. Just sods law it seems to happen when she's driving and in a crap mood.
Have posted on the Volvo forums too but there's much head scratching and looking at the ground going on, which is odd as for such a common issue on these cars (and I assume, the Focus too given it's all Ford stuff) then you think somebody, somewhere would have pinpointed the issue... be it a dry solder or a fractured track or a certain pin that creates issues. If it was a one off fault with this car, I'd understand the lack of solutions but for something that seems so common... bar cleaning the pins... or replacing the CEM and loom... there doesn't seem to be anybody who's managed to identify the problem.
Will keep going with it... it might happen en route to work later... or I'll be back in 2024 with an update.
Cheers
Granted, it's behaving fine having been removed yesterday but that's the issue. It'll run fine for any given period of time, then have a meltdown but as soon as you move the plugs, it clears and it's fine for weeks again. However, poking, prodding and wiggling the plugs and wires doesn't seem to effect it in any way which does slightly contradict a poor connection theory as you'd expect some sort of hiccup. Or indeed, having been removed and cleaned several times, any dirty connection would be resolved.
I'll pass on the electrical grease, granted the pins and terminals should be spotlessly clean and free from any contaminants following yesterdays total strip down of the CEM itself and granted, it may have actually cured the problem but I won't know that until it does it again... or doesn't and that could take weeks / months to happen. Just sods law it seems to happen when she's driving and in a crap mood.
Have posted on the Volvo forums too but there's much head scratching and looking at the ground going on, which is odd as for such a common issue on these cars (and I assume, the Focus too given it's all Ford stuff) then you think somebody, somewhere would have pinpointed the issue... be it a dry solder or a fractured track or a certain pin that creates issues. If it was a one off fault with this car, I'd understand the lack of solutions but for something that seems so common... bar cleaning the pins... or replacing the CEM and loom... there doesn't seem to be anybody who's managed to identify the problem.
Will keep going with it... it might happen en route to work later... or I'll be back in 2024 with an update.
Cheers
The Volvo chaps seem to be in agreement that's it's a pin or pins reading contact. An associate at Volvo says they do a pin kit for the multiplugs, as over time they get slack... we're taking fractions but enough to momentarily break contact, more so when cold.
Hence, that was my thinking behind conductive grease. If we're talking the tiniest of gaps then I assumed grease (or similar) would perhaps bridge said gap. This seems most likely given as soon as it's disconnected and reconnected, the issues clear immediately.
The other option is to gently bend the pins a fraction to increase contact pressure between them and the female terminals in the plugs. Or try and close the female terminals slightly. Or fit new pins but I'm not sure my talents extend that far to be honest.
Hence, that was my thinking behind conductive grease. If we're talking the tiniest of gaps then I assumed grease (or similar) would perhaps bridge said gap. This seems most likely given as soon as it's disconnected and reconnected, the issues clear immediately.
The other option is to gently bend the pins a fraction to increase contact pressure between them and the female terminals in the plugs. Or try and close the female terminals slightly. Or fit new pins but I'm not sure my talents extend that far to be honest.
Can't be bending the pins a little as they will no longer line up with the plastic guide holes of the plug
Not a good idea using a conductive grease as a filler
New terminals would at least prove something, even better if there is a repair kit that comes with plugs/terminals already fitted to fly leads that can be joined to original loom
Not a good idea using a conductive grease as a filler
New terminals would at least prove something, even better if there is a repair kit that comes with plugs/terminals already fitted to fly leads that can be joined to original loom
Gassing Station | Home Mechanics | Top of Page | What's New | My Stuff