98 E320 Turn Signal Relay Problem
 

My daughter's 98 E320 has recently had a problem with her turn signals in that they will not work, emergency flashers too.

When I pull the under hood relay p/n 002 542 03 19, or even touch it, the signals and flasher start working again. This has happened now about 3 times.

The relay appears to be a solid state unit as the base is potted with epoxy. I'm assuming it is faulty, but would appreciate any thoughts on the subject as it's expensive, and, while we are at it, the fuse list calls for the one handling the turn signals to reside in #41 location. There doesn't seem to be a #41 as both under the hood and next to the battery there is about 26 locations and about 10 or so on the side of the dash. Any ideas where it is???

Many thanks,
Ron

That is the front SAM unit & can cause that issue.

SAM = Signal Acquisition Module, (I had to look it up and thought I'd save a bit of head scratching by posting). Thank you!

Any idea where the mysterious FUSE #41 is located on this '98 E320 that feeds the turn signals?

All of the lighting fuses are located on the driverside fusebox, part of the headlight switch

I finally bought a brand new relay ( or SAM) from the dealer p/n 002 542 13 19 and it seemed to fix the problem of intermittent operating signals or wipers. Everything was fine for about a week, but now it has started again. My daughter now has no signal lights again.

I have now:
1. replaced the console switches
2. checked all fuses
3. Replaced the SAM
4. Pulled battery power so as to reset the computer

Thoughts, Gentlemen?

Still most likely the SAM unit.
The only other choice the the switch.

Was there any signs of WATER intrusion in the original unit?

No water intrusion into the fuse/relay box under the hood, but slight evidence of "liquid" into the console switches.

Console switches were replaced.

Just took it out on a rainy day and both the wipers and the signals would work intermittently. This could happen and then both would start working again in a few blocks, then crap out again, then would be o.k.

My daughter took it to our local dealer, Smythe, and they wanted $400 to run a diagnostic on it. They also said that it was likely the problem was coming from the steering column switch - which they would be glad to replace for $700 + labor.

Is there any way to check the functioning of the SAM other than to install it in another car? (This is the green Siemens relay under the hood, p/n 002 542 03 19)

Thoughts, anyone?

The part number 002 542 03 19 is for the washer pump relay. The SAM relay is on the underside of the fuse panel.

Robert

I finally got the SAM unit located and pulled it. It is dry, looks fine as does the wiring to it. so there is no obvious reason to suspect it.

Questions:
1. Before my daughter springs for a lot of $$ for another unit, is it possible that replacing any of the 5 multi function relays that are above the SAM will cure the intermittent wiper/turn signal problem? I have (1) black 002 542 11 19, (1) green 002 542 03 19, (2) yellow 002 542 14 19 and (1) black 002 542 13 19 When the wipers crap out, they totally crap out - no wiping at all and also the turn signals go at the same time.

2. Is there any "art" in removing the cover of the SAM or is it just a matter of prying the thing apart - and probably damaging it. Some posts have reported solder cracks that can easily be repaired, but this one just doesn't want to come off to reveal the pc board underneath.

3. Anyone had experience with http://mandbspecialist.com/mercedes-electronic-parts-repair.php that advertises they repair SAM units?

4. I understand that when you replace your SAM, it must be reprogrammed. Is this strictly an MBZ dealer function or can it be done at a decently equipped independent or, hopefully, even by a shadetree DIY guy?

Thanks and Happy New Year