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Does anyone have a wiring schematic for the rear fusebox for a 2011 ML350 bluetec? Trying to see why I don't have power to fuse 72, possible trace it back.
Thanks for the reply Maj. Dundee. I need to clarify that I meant fuse 70 not 72.
From what I understand that info is for the pre-2006, I have a 2011 and there are 3 relays across the area you have highlighted (S,T and L). When I took the ML350 in for programming I had them install 2 new relays in position L and U as per (AN31.19-P-8080-03GZB). I think, like you said, L gives power to fuse 70 which if I'm not mistaken is just 12v to the trailer (battery, etc). BUT, even after swapping L with a different relay of the same type, it still doesn't power fuse 70 (KOn or KOff). Sorry for the ginormous pics!!
Yes, as you know after installing the an OEM hitch package (I got all mine from a wrecking yard), the rear SAM needs to be SCN coded. The dealer had the data card updated to included 550, but still they weren't able to get the trailer lights to work. They said there is no power at F4f70 and suspect there is an issue with the fuse panel or one of the relays. Hense, I'm looking for a schematic to trace the power back and figure out what turns on relay L. I've got power to the relay but I can't figure out what closes the relay to allow power to f70, if in fact relay L powers f70.
First of all, why didn't you mention the fact that you retrofitted a trailer hitch? Look at what is required to make it perform correctly. It's monumental.
Secondly, you originally gave the wrong fuse number which caused me to look up different diagrams. Below is the wiring diagram for fuse #70 which is activated by relay KU.
Thirdly, you brought it to a dealer and they couldn't find the problem and they couldn't even program it correctly, if they knew how to do it.
Thanks Maj. Dundee, the hitch is installed (pretty easy 3/10), and wiring complete (5/10 difficulty due to MB parts department not knowing what wiring harnesses were needed). Overall, pretty simple for those that know their way around a shop. The issue is programming of CANBUS systems. It seems they may have programmed my rear SAM but aren't able to get things working because there isn't any voltage to f70. At $158/hr for them to trace down the problem, I'm going to track it down myself. I'm no stranger to electronics but without STARDiagnostics or even with it they couldn't immediately figure out the problem. After 2 hours of them trying to program the SAM over and over again, I figured I should cut my loses ($220), plus another 2 hours for them to trace back the power problem. In the meantime they keep telling me I need a new rear SAM, the kicker, the dealer used a donor SAM (new off the shelf) which they still couldn't get working.
Ok, that schematic is very hard to read but I think I got what I needed off of it. KL relay powers f72 which is not used for anything and it is a normally closed relay single throw. Relay KU looks like a double throw but I can't tell if it's a normally open or closed circuit. That definitely isn't the relay they put in there. They put in a normally open/single throw relay. This might be my problem. Can you tell me what relays are suppose to be in KL and KU? They installed A 002 542 92 19 in both KL and KU. The socket for KU looked like a double throw but I thought they knew what they were doing.
Ok, that schematic is very hard to read but I think I got what I needed off of it. KL relay powers f72 which is not used for anything and it is a normally closed relay single throw. Relay KU looks like a double throw but I can't tell if it's a normally open or closed circuit. That definitely isn't the relay they put in there. They put in a normally open/single throw relay. This might be my problem. Can you tell me what relays are suppose to be in KL and KU? They installed A 002 542 92 19 in both KL and KU. The socket for KU looked like a double throw but I thought they knew what they were doing.
If you look at post #2, the third part #002 542 92 19 is for relays S-T-U. But relay L has its own number. M/B does not know what they are doing.
You had better read all of the PDFs that I supplied you with, in which it calls for the replacement of the rear SAM PDF 1G and the cooling fan PDF 1I. Read, read, read.
Last edited by Maj. Dundee; 09-29-2018 at 05:26 AM.
Looks like the relay A 002 542 11 19 has been superceded several times by mercedes to 002 542 83 19 and the latest 002 542 92 19. I did swap out KU with the proper relay and wa-la... power to f70.
Sorry to break in to an old thread, but I am looking at an issue on a GL500 X164 related to fuse/relay/sam behaviour. @Maj. Dundee your information seems very detailed and to the point; would you be willing to look at my post on the X164 forum?
Many thanks in advance for any help or advice.
Sorry to break in to an old thread, but I am looking at an issue on a GL500 X164 related to fuse/relay/sam behaviour. @Maj. Dundee your information seems very detailed and to the point; would you be willing to look at my post on the X164 forum?
Many thanks in advance for any help or advice.
09-26-2018, 04:45 PM
