SAM module.......is it at risk?

[Spokerider 0]

Guys, 

 Can you please give me some input on the SAM module, for a 2006 cdi? 

 So far, no problems with mine......but a friend has a 2005 cdi that had water get into the SAM. While driving, the engine shut down and now no go. Apparently, the SAM is at fault.

 

 How / why does this happen? I think the SAM is under the dash, about where your left knee is positioned. How does water get in there.....when it's inside the cab? 

 

 What can I do to keep this from happening to the SAM in mine? I'd imagine that others living in the Pacific NW, that get the rain that we do here, have had problems.

 

 Thanks for your thots.

[Nigel 252]

There was a recent discussion about windshield leaks.  I think it was chopper who said he could see his windshield move  every time he closed the door.

 

Nigel

[Sydney 214]

I was looking at my SAMS location. I doubt the water from a leaking windshield would drip directly into the SAM. I would guess if a windshield leaks, the water would drip onto a wiring harness then wick directly into the SAM thru one of the many plugs.   That would give the water direct access to the circuit board.

[Willys 651]

I just sealed up my little silver box at the passanger foot location. Yesterday I started getting warning lights staying semi lit, and the door beeper binging every now and then. Took me forever to pput two and two together to realize it was the door chime making the noise...lol. Anyway....I went after the box, it had already been out and move up onto the firewall area off the floor. It was soaking wet! Inside and out, even the carpets weren't wet! WYF...?  So I asumed the same thing, water had simply wicked down and into the box soaking the board and shell and plugs. So I warmed her up with heat gun at a distance as it can melt circuit boards. Use a hair drier it's saver if you do not know how hot your gun gets! I then used dilectric grease to brush onto pins and plugs and also the back of the plugs to stop it happening again. i also used draft stop type sealant as it's peelable if you decide you changed your mind. To seal the acutal box up. I worried about it getting warm, I took her back to Glenn for a visit 7-8 hours of driving today and it's still cool to the touch, so no heat build up and dry , It poured rain all the way there and back....I also relocated it to hang from the air bag cross member under the dash. So far away from any , well hopefully water penetration locations. My car has been sealed I thought tight, but obviously not.  The rear corner windows are the worst leakers becides the windshield. I siliconed them tight, no water get in from there now, I also do not see any tracks from the windshield either.  Hmmmm....?

 

So do your research and check everything, all ground that you can find on the car, take them all off and wire brush them all even if they look new.  BEWARE.....make sure you have the radio code BEFORE you take the neg from the battery!!!!!   I did but it took me 2 hours to find the card. My beater I lost the number so I now need the radio hacked.  BEWARE!  IF you do undo the ground from the battery, make a jumper so it is temperarily still grounded IF you do not have the radio code.

Good luck!

 

I have check the front two computers for water damages and so far they both look like new, no solder issues or burnt pins etc etc....again check everything before saying it's good to go. You'll need a head magnifier to be able to see the solder joints well enough to accurately see if they are solid or not.

[MikeT 692]

Reminder: Don't use regular silicone when sealing electronics!

[Willys 651]

I only sealed the box not the board itself. I have already learned that lesson many decades ago....this draft stop works well and is remobable so you can reopen the case or simple undo what you have done.  Just so others know what to use. To reseal a repaired solder point I use clear nail polish.

[smartdriver 49]

22 hours ago, Spokerider said:

How / why does this happen? I think the SAM is under the dash, about where your left knee is positioned. How does water get in there.....when it's inside the cab? 

 

My first smart had a severely damaged circuit board due to water incursion. The problem was compounded by the fact that it had a sick battery which I frequently overcharged and it is likely that sulfuric acid fumes from the unvented battery (there is supposed to be a vent hose) combined with the moisture to create acid which ate away metal traces not only on the board,but on the integrated circuit chips.

 

Where did the moisture come from? In my case I am certain it was not a leaking windshield. My belief is that it is condensation from a cold environment or the air conditioning  which collects on the wiring harness and wicks into the SAM.

 

After repairing my SAM, my solution was to place a sponge between the wiring harness and the SAM to collect any condensation that might accumulate on the wiring harness.

 

So far, so good, four years later of being parked outside in the worst Toronto weather, no further problems.

 

My feeling is that all smart owners should do this as a prophylactic measure to not only protect the inside of the SAM, but also eliminate corrosion on the connectors which has lead to so many headlight and water pump failures which then requires the relay fix.

[Willys 651]

I like to use a small child's paint brush and dilectric grease and carefully brush the connection points with it as it keeps the moisture off said connectors.....I wouldn't paint the entire board with it as it does conduct a very minute amount of juice so i was told by a Electronic Engineer....but if painted on with a small delicate brush,just the contacts, the amount is neglegable and won't conduct  enough to cause any grief at all. The rest is up to you to decide what is best....you could always just drill a few holes in these containers which house the electronics to allow any moisture out if that pleases you,  there are many methods to chase to try and fix the problem. BUT IF you can stop the water getting into the box in the first place and  the fact the box is sealed in it'self doesn't make condensation then i think you may have a winning solution.

[Spokerider 0]

Good info guys, thank you.

 

 I still have not looked st the SAM, it's my wifes car, and I need to pry it away from her first, so I don't have an image of it in my head yet, and where exactly it is oriented.

 

 So it seems agreed upon, that water getting inside the SAM is the known culprit to it's demise.....just don't know the origin of the water for certain, may be more than one route or origin onto and inside the SAM.

 

 About relocating it elsewhere under the dash........is the wiring harness going to it, long enough to easily relocate it? What about orientating it, so that there is a "dip" in the wire harness, so that any moisture on the harness won't be wicked "up hill" into the unit? Possible?

 Also.....why not use regular home building silicone for sealing the box? 

 Draftseal......any particular brand? How is this product different from silicone? 

 Also, would you recommend dielectric grease for the harness contacts / corrosion inhibitor vs application of electric contact cleaner? I always thot that dielectric grease is non-conductive, and should not be used where good electrical contact is needed / desired. 

 

 

[smartdriver 49]

The SAM is located above the driver's knees under the dash and is covered underneath by a cardboard cover which must be removed for access.

 

The wiring harness is very short. Moving the SAM would be an issue. Re-orientating it by rotating it 90 degrees might be possible so that the water won't wick down the wires into the SAM.

 

It is my opinion that sealing the SAM is unnecessary. The water is wicking into the connectors, not the SAM cover.

 

I had one pin badly eaten by corrosion. Fortunately there are spare, unused pins, one of which I was able to remove and use as a replacement.

 

It also might be of advantage to use a contact cleaner on the connector pins such as such as Deoxit.

 

My opinion is that contact cleaner and simply placing a sponge between the harness and the SAM is likely adequate protection.

[Nigel 252]

From what I have read here over the years the biggest issue with the sam is the load being transmitted across the connector for the headlights and fuel pump.  Several have suggested relays for those circuits as a preemptive measure. 

 

Nigel

[smartdriver 49]

9 minutes ago, Nigel said:

From what I have read here over the years the biggest issue with the sam is the load being transmitted across the connector for the headlights and fuel pump.  Several have suggested relays for those circuits as a preemptive measure. 

 

Nigel

 

Although I don't disagree about adding the relays, it is corrosion on the contacts which is causing high resistance and heat damage to the headlight and fuel pump connectors.

 

Some apparently had compounded the problem by replacing the stock headlights with high intensity headlights.

[Willys 651]

Dielectric grease isn't supposed to be conductive, but if lathered on it can carry a very small supply and seeing as this car is so sensitive electrically use it very sparingly and you should be fine. Hense the paint brush and not just filling the plugs up and pressing them together until it oozes out everywhere. I did this on my bike and it had electrical issues and an electronic eng. explained this to me. I simply wanted to stop any calcium from filling the plugs as it had the last time I rode the Dempster Highway where they use calcium to keep the dust down. It worked well for that but the amount i jammed into the plugs made things happen even on the KLR. So gently paint the stuff on everything in the plugs and connections and it is great stuff to keep corrosion and water away.
As for the draft stop, it is removable, simply get your finger nail under it and it'll peel off. Unlike my favorite 100% silicon, not a chance in hell...lol.  But it seals and holds stuff like no other...lol.  Draft stop simply seals the items to help keep water out. So with that sealing the joint of the case and dielectric grease keeping the water out of the plug and wires, it should be water tight? I didn't do the SAM, but the silver case by the passanger foot well. The SAM will get the dielectric grease and maybe a fresh coat of clear nail polish on all pins etc to keep water out of any possible entry points. Then maybe a few holes at specific low areas in case water does get in to it. That'll allow any water to drain and not sit soaking thing.