Hi All,
I was looking on the web for any pictures or drawings of the inside of the SLA since I might have a problem with mine. I couldn't find any info about the internals. Most posts are about how a drink was spilled on the SLA, and it stopped working. I was wondering why a spilled drink could ruin the electronics - most electronics are conformally coated to protect them. I went to a pick a part to find a SLA. I couldn't find a crossfire or SLK SLA, but I was able to pull a 2002 CLK 320 one. I think it should be representative of the crossfire SLA. Taking it apart was fairly straightforward, except for the part where I opened the small box that contains the slide contacts - the plastic tabs were extremely brittle, and I broke most of them. Anyways, I think the reason spilled drink can ruin the SLA is that it gets inside the slide contacts (Figure 3 in the attached PDF), isolating the contacts thus preventing the SLA from knowing what gear it is in. Of course, the unfortunate part is that the slide contacts are the last thing that comes off. The white gear looking piece actually is captured by a pin that protrudes from the D profile tube. My guess as to how it works: as the tube rotates, the captured pins move the slide contact. There are clear spots on the rails at different points, so when the slide makes contact at those points, different pins are shorted together (the pins are to the left of the picture). The pattern of shorts or resistance differences corresponds to the position of the shift lever.
Hope this is helpful to someone.
-Jerry

 

Interesting, thanks for the photos.

 

1) WHAT? I've earned a living in component-level electronics since 1983 and I'd not say that, not at all.
2) You now have a full understanding of just how "vulnerable" many of the electronic/electrical components of these cars are.

Iv'e been on this board since 2009, the number of us who have experienced chemical/water/soft drink damage to modules (and NOT just the SLA) are endless. EXAMPLE: Water damage to the CLP/SSM has to the the 3rd or 4th leading cause of a convertible top that wont move, all it takes is a TINY amount of water migrating over time, down the wiring harness. EXAMPLE: The SLA, which you just documented better than anyone ever has.

I gotta say, being a "manual only" guy, I have often wondered just what was in the SLA, I knew it had considerable electronics, as it talks to the ECU on the CAN BUS.

MOD NOTE: This thread in now a "sticky" and will remain here, as you put it in exactly the right forum. This little project of yours was a great idea. The SLA is one of those "nothing much in the manual" modules and we have LITTLE to go on apart from what we contribute as a community.