When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This a GOOD one, for all the electrical and wiring GURUS (SOLVED)
i have an ML63 amg. and the problem that i am having is the wipers,
rear and front wipers were not working, checked fuses relays, i had to change circuit 15r relay and everything worked but the front wipers, took out both SAMS and they were in good CLEAN condition, since i had them out sprayed them with contact cleaner and put them back in, now here is where it gets tricky, check front relays for the wipers, they both have 12v on terminal 30 and on terminal 86, . 30 amp fuse (100) is good as well, when i checked the ground signal from the front SAM that activates the relays found out that the ground signal had 2.4 volts. no wonder why the circuit wasn't closing.i also checked the green and black cable that goes from front SAM to the relay box for continuity, the cable is good, if i test it disconnected from the sam. (pin 9 i think on the 40 pin connector to the fusebox), but if i plug it, it carries voltage.
now i am also assuming that the SAM activates the ground signal to wipers via a relay on the board i can hear it click once i activate the wipers,
now the questions are
could the front SAM be damaged?
could a rat have bitten a cable and now it has a short?
could some other positive cable be making contact with the ground cable and be shorting it?
could the ground signal that feeds the relay inside the SAM be corrupted?
could anyone provide a from sam complete schematics as well as pin out for every connector?
Don't you have a scanner? You cannot own one of these vehicles without one.
The wiper system is not activated by a ground, it is activated by turning on the stalk. Check ground W16/3. Pierce the cable with a thin pin and see there is ground.
Got it sorted, it was a loose fuse next to the batery, took it out to inpsect since it was hard to test under the seat, and problem solved, i dont know exactly what that fuse operates but got things working, it was the third fuse up.
Major, thank you for your reply and help, you are a big pillar to this community.
Fuses don't come loose which means that you were fiddling around in the front SAM fuse box.
Now you got your wipers working.
Fuses do come loose, if someone mistakenly put the wrong amp fuse or the wrong type or if you put the fuse in the wrong direction. My mechanic sent his son to help me, and the kid put standard fuses where they should’ve been mini, and they popped up. Sadly, I have learned that no one can really be trusted, to work on your vehicle.
I don’t believe a mechanic won’t remove a fuse for a different vehicle they are working on, and wait till you come back with complaints for the issue. Then they have a reason to charge you again. what it boils down to is having to learn a few things about my suv, so they don’t see me as prey when I book an appointment. I know my vehicle is suffering some serious issues, it has leaks for Mb’s sake, but how does a relay magically go missing, or any fuses for that matter.
I’d like a lock put on every fuse box, and a colored picture diagram in the inside cover, so I know exactly what fuse should be there and what color it should be. Why is this so hard? It’s Mercedes’, we spend thousands to own one, God forbid they should make some adjustments that provide simple, visible assistance.
And stop putting in features that continue to run once the key is removed. When I figure out how to rip the SOS teleaid and call crap out, I fully plan to do so. That stupid thing sounds like I have a built in fax machine inside my stereo.
I have some questions because I'm at the same stage you were at the time of the original posting and was about to clean the front sam pin 9 grn/blk wire connection and was also searching x25/2 connector on how to access it, as it was mentioned in a related thread after reading yours, so that's why I clicked on this thread, because that was my next plan if this didn't work. I do have a fault scanner and I think the code is actually 902c which means the wiper relay f58kB is defective or missing or the feed line has open circuit. You ended up saying it was just a fuse beside the battery but I checked the fuse diagrams and nothing relates to the front wipers, however some relate to the front sam. I wonder did you test the wipers again with the doors and hood closed after checking pin 9, before checking the fuses? because you posted originally at 12pm then again at 3:02pm and had it solved on the first day, so maybe you got stuck then posted this and determined it was just the fuse being loose? Also how long ago did you replace your battery? My battery is 8 years old and I'm trying to milk it until the car doesn't start anymore, so my theory is that just the slightest amount of corrosion on any electrical contacts might not trigger the relay which triggers the wipers. I wonder if it's possible that fuse you thought just by taking it out and putting it back in, cleaned it a bit and brought more power to the front sam, or it might have just been pin 9 you were testing when you made the original post. I'm just asking here because seems easier than accessing the front sam if I don't have to. I have had this problem for several months now on and off and studied wiring diagrams and taken apart the engine fuse box to clean and finally got to where I am now. I also recommend a bottle of rainx spray for people that are trying to fix wipers, this way you can still drive while you figure out how to fix them. X25/2 was the connector in between the wire to the front sam and the front fuse box. I remember after cleaning out the engine fuse box the first time my wipers worked for about a month then stopped working again, thus my theory on the battery getting lower and not enough voltage to trigger things. I guess I will try cleaning all the fuses under the passenger seat as well as the pins to the front sam, unless you are sure it was just that one fuse, or you just happened to remove it and test the wipers and thought it was the cause instead of just the pin 9 being cleaned, which is basically my question written in a very long way.
Last edited by mastermercedes; 02-08-2023 at 09:51 AM.