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Mercedes-Benz R-Class Electrical Problems
PF_Flyer
Member Posts: 9,372
Have an electircal problem with your vehicle? This is the place to work it out.
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I have seen a vehicle with this issue. The bullitin states adjust latch/ do not replace. We tried to adjust 4 times and ended up installing a new latch to remedy........
We had a dvd player that crapped out and the battery keeps draining. The dealer has had the car for over a week and they have no idea why this is happening.
And come to think of it, the hatch doesn't always close properly.
I love the way the car drives, and kids love the space, but i gave up my old Merc wagon for the R350 not just because the kids love it.. but becasue of R-E-L-I-A-B-I-L-I-T-Y. I can't explain this so far & when the technician came prompty this morning (same person as first time), he couldn't either. Told me definitely there was something unnecessarily draining the battery and this was/is very odd.. i have to take it in for service now for them to diagnose The car is 12 days old!. Do i have a lemon? (gosh hope not because i love the interior, the drive etc), but this is unacceptable.. Will see what the dealer says & does..
Like you, we love the car. It drives great, has so much space and the kids love having their friends ride with them. I don't see us keeping it once the warrenty expires unless this problem is diagnosed!
- electric tailgate fail, adjusted twice.
- rear windows stopped working.
- SRS red warning light. Dealer replaced airbag module. Light is on again, six months later
- battery light comes on periodically. Dealer has fixed it three times, and its on again now
- low antifreeze light comes on periodically. Dealer has fixed it twice, it's fine now.
- installed tow package, and it took the dealer 7.5 hours to connect the harness. After discount, it cost me $500 to install the wiring harness (which is the same as ML harness)
- non-xenon headlights. Had to return to dealer twice to adjust headlight aim
All these are minor problems, and were fixed without question, and without drama at the dealer. However, for a car that cost $60,000 with tax, I should not have to take it back to the dealer every three months for some other goofy problem. We aren't happy owners. Yes, its comfortable, drives great, looks good. But, it's big, can be hard to park, and has to visit the dealer far too often.
Independently I would not be too worried, but collectively all of these happening within a few days of each other gives me some concern. Took it to the deal this morning and of course the check engine light is no longer illuminated, the temp gauge seemed to be working normally and haven't filled up the tank again. Just had a call from the MB Svc Mgr and he told me they had were able to diagnose some of the issues and replace a few sensors, that should take care of the check engine light & external temp readings and he was going to send the car home with a tech and fill up the tank to see if they could reproduce the fuel level reading. If he can then they would have to take out the gas tank and then replace some additional sensors for that as well.
I am hoping that all of these are not representative of a larger issue...any thoughts?
The dealer told me that there were too many codes coming up to clearly identify the source of the problem, but they did isolate the fact that underlying issue was low voltage. They initially replaced the battery and ran some overnight diagnostics to check the battery drain in the morning. This morning they told me that there is definitely a drain coming from somewhere, but not sure of primary source. They think it may be coming from the fuel pump since my last gas gauge issue identified in my 11/10 post. I find it interesting though that last week that was nothing to worry about and now they think it is the cause of the problem.
After reading some of the other posts I do not get a level of comfort that they will be able to isolate and fix this issue as clearly there seems to be some kind of MB mfg default with no known resolution.
Has anyone that has experienced this low voltage/electrical problem been supplied with an actual resolution, other then a new vehicle?
I agree, watching the flatbed tow our 2008 - 3 times!- was no fun!
Interesting, my dealer never mentioned a steering control unit as a potential problem. What he did tell me though when I my car was dropped off yesterday with this low voltage issue is that he had another R350 in the shop w/a similar problem.
A quick google of "MB ISM Motor" revealed the exact same problem resulting in the “DRIVE DIRECTLY TO GARAGE WITHOUT CHANGING GEAR” message that I received.
They told me that basically what happened is that the ISM Motor is defective - this is the part that controls the paddle to shift from park to drive & reverse. The faulty ISM was preventing the car from shifting gears, hence the message above about driving without changing gears (a physical impossibility, but let's not split hairs). The drain came from the fact that problem with the ISM Motor prevented the car from recognizing that it was in park and therefore resulted in the repeated beeping and the dome light to be illuminated with no way to shut either off - causing the battery to drain.
He is replacing the ISM Motor tomorrow, hopefully that will do the trick. I'll post an update if it worked... or didn't.
Secondly, the auto light switch appears to have a mind of its own, sometimes turning the headlights on in the middle of the day in bright sunlight or refusing to turn the lights on at dusk or in low light conditions such as very heavy rain. The dealer has replaced the optical sensor but the fault persists.
Finally, the front parking sensors seem to go crazy on hot days often emitting continuous tone and full led signal for several minutes for no apparent reason. This only affects the righthand side of the vehicle. Dealer says he cannot duplicate the problem.
I would very much appreciate any advice or information regarding these annoying faults which spoil an otherwise excellent vehicle.
Did you ever find out what was going on with your tail lights? My R500 does the same thing. Also my horn has gone out. I'd feel silly if I took it in and someone tightened one screw and charged me $300. I'd love to know what was done to fix it.
Thanks! Don
Took the car to the local Benz dealer, they were kind enough to fix it free of charge, to me that's indication that they were having problems on many of the cars. If I understand the fix, it has something to do with the light socket making contact to the tail light housing, or lack of making contact. 50,000.00 miles seems to be the magic number, under that and they make a free fix. Spoke with another R350 owner that had the same problem with the tail lights. Can't help you with the horn problem. Hope this is of some help. Take care & travel safe
Replaced steering column
tail lights kept burning out
cruise control went out
windshield wipers went out
The car would cut off constantly
Harnerss wiring issues
They tried to blame me (coin in cigarette lighter).
Most of my work was covered under warranty. They even paid me out some money. After the warranty ended. They want me to pay. They have had to replace the fuse box.....maybe about $5500.
Major electrical issues.
I have the same exact problems about not being able to shift gears. I just want to know if the ISM Motor replacement actually worked or not.
I have a 2006 R350. It just started showing this problem intermittently and is very annoying.
Since then I have had numerous issues unrelated to the ISM, the last one being a leak in the sunroof that wasn't visible in the cabin of the car, but apparently channeled down into the battery compartment which is under one of the seats. This caused the battery to short out every few days. Another trip on the dreaded flatbed (4 in 2 years) for another 2+ week stay at the dealer where they couldn't figure out the problem. I guess I'm lucky all of these ridiculous repairs have been under warranty. Just very, very poor quality vehicle.
Case in point - the tail lights. Tail lights on both sides have failed repeatedly. This isn't a matter of the tail lights burning out. This appears to me to be a design flaw in the tail light assembly that relies on pressure point contact between the tail light casing and the bulb socket to conduct power to the light (as opposed to wiring that goes right into the bulb socket). Over time, it seems that the contacts on the bulb socket bend to a point that they no longer make contact with the metal on the tail light casing (which I believe is conducting the power). We've "fixed" these several times, only to have them fail again shortly after fixing. (Interestly, other lights in the assembly rely on this same design but have not failed.)
Has anyone else experienced this on their R-Class. I assume so given what our local Mercedes mechanic tells us (and the knowing shaking of his head when we present the problem to him).
Appreciate any feedback from other RClass owners.
I am interested in buyiung an R350 4 Matic - should I or Not buy it?
regards
Stay away of the 2006 and 2007
Just wondering if you can share some more information. We just bought a R350 2008, just over 4 weeks ago. Whole host of issues, including replacing front light within 1st 2 weeks. Most recent issue, is leaking sun roof that penetrated in to floor of car casuing battery damage. MB are stating not under warranty and looking for 9K to repair which is absurd. Any further information regarding your similar situation with sunroof would be very appreciated.
Just wondering if you can share some more information. We just bought a R350 2008, just over 4 weeks ago. Whole host of issues, including replacing front light within 1st 2 weeks. Most recent issue, is leaking sun roof that penetrated in to floor of car casuing battery damage. MB are stating not under warranty and looking for 9K to repair which is absurd. Any further information regarding your similar situation with sunroof would be very appreciated.
BTW my latest issue is that there is no longer any working audio... no radio, no sound from GPS, no ipod, etc.
I am thankful that I replaced this lemon with a Volvo XC90 a few months back, which so far has been very positive. Doesn't ride as smoothly as the R Class, but at least everything works as designed. My R Class has been sitting in my driveway since there is no benefit for me to turn it in early.
Good luck and please provide an update as to how it works out.
BTW I finally turned my 2008 R350 back in when lease expired at the end of Feb. Good Riddance! I had replaced it with a 2011 Volvo XC90 which I have been driving for about 6 months & very satisfied with so far. Nothing spectacular, just solid, reliable, easy to drive, comfortable, no major drawbacks, overall a good value.
I changed it last November for a 2011 GLK350 Fantastic Ride and build like a tank, proudly made in Germany! absolutely no problem whatsoever.
I lost money on the R350, they updated the software, and some other things but they could NEVER pinpoint the random shifting problems and shake ups.
This adds up to alternator problems, early serpentine failure, battery failures, the panorama roof slowness, the random tailgate light problems, etc.
And the last one before I traded in, the taildoor shocks were broken. Bill to fix those around a $1,000 that is when I decided to trade it in.
Mercedes Benz dark ages of electrical problems between 2001 until 2007, especially the ones assembled in the USA.
Finally in 2008 they increased the quality again.
2006 R350 first batch of R350s it is like the Gremlins built those cars. I would stay away from them.
We got rid of our R350 (first year model) and we've been happy since! There were just too many electrical problems that it wasn't enjoyable car ownership with all these trips to the dealership for the annoying myriad of problems, mostly electrical.
It's a shame as most Mercs do handle well, although my grip of the R350 besides being a bit underpowered for the weight, is the dim standards headlights (I couldn't get one with the HID lights with the one I bought at the time..)
How are the GL's in terms of reliability and lack of trouble??? Test drove one and it was fine. How about the E350's??? Hadn't dared consider buying another Merc because of bad experience with our R350.
I'm curious, what prompted the steering column replacement? I have a 2006 R350 and I'm starting to get a clicking and thumping that I can feel under the front floorboards when I make a turn. I'm trying to pinpoint the issue before taking it to my MB dealer. I'm glad I took out an extended warranty, I'm having lots of problems (I'm happy to post the list of issues if anyone is interested) including some possible transmission issues
Cheers,
-Grasshopper
Did you ever have a problem with the r350 not shifting into gear?
I took mine to MB dealer and they said I needed a new tranny (for $8200)! I'm getting a second opinion today.
If anyone has any input, let me know.