Sid3ways

Hi all!

I have a 2009 GL450 that had the wipers decide to go out on my wife when she was driving on the Turnpike while raining. We haven't had this issue before and we've owned the vehicle for about 6 months now. After searching online fast about the hood needing to be closed for wipers to work I then had at least a starting point.

When I got to the vehicle the wipers worked only about 10% of the time when I turned the car on/off and hit the stalk. I looked at the hood closed switch and saw a small piece of debris where the contact was so I lodged that out and it seemed after shutting the hood, the wipers turned back on and worked the rest of the day, I thought all was well.

Today I got another call from the wife when taking the kids to school, the wipers stopped working on the way back home (while raining). So apparently the debris wasn't the root cause for what is going on.

I don't have any diagnostic tool, if I purchased one, would that go deep enough to tell me if there is a sensor not being made? My only thing to go off right now is the hood switch is going bad? I thought I read somewhere though that over 5mph, the wipers should work regardless of that switch being made (for obvious safety reasons). I also read something about the drivers door switch but would that be the same assumption with speed and overridding it? If so, something else is causing the wipers to stop while the vehicle is driving down the road at 70mph.

Any help is GREATLY appreciated!!
Andy

Plutoe

FYI the handy dandy OBD readers can't read the C and B codes that are apart of the extended vehicle system which include the wipers bla bla.----all you can do is check the under hood fuses and relays that apart of the front SAMs---if all good--find some one with DAS Xentry to quickly solve your problem!!

Sid3ways

I have taken the vehicle to a local indy that works on European cars and he has had the vehicle for a couple days now. He just called and informed me that the issue is that it needs a new front SAM module. He mentioned he was surprised that we didn't get any SRS errors on the dash as that generally points quickly to a SAM module.

He did mention upon his tests, the error code that was showing up in the diagnostic was a stuck motor BUT he said that he was not seeing the wiper signal becoming activated when turning the knob on the wiper stalk. The rear wiper works fine and 100% of the time when requested, it is only the front wipers that do not work anymore on any of the settings. The fuses checked out and the cluster (wiper stalk) checked out he said.

I have a feeling that since I have the stalk working fine, and no SRS errors that it may NOT be the SAM module but a relay like you had an issue with. I'll certainly test the theory with someone in the passenger seat, I don't believe I've had someone in the passenger seat when trying this other than the initial time they stopped working. While that's probably shooting in the dark, it is worth a try.

I'm not looking forward to spending the $1,000 to replace the front SAM module right off the bat without bouncing this off of a few people online. Any thoughts?

Plutoe

On this VIN there is no wiper relay--that function was incorporated into the front SAM

Sid3ways

I'm not sure, this is the very first time I've gone to this mechanic, they specialize in European vehicles so I took it there. Where is the front wiper relay located?

Plutoe

There is no plug in relay on this VIN!!

Sid3ways

Is there a relay map online somewhere? I can't seem to find anything.

I have the vehicle in my possession now as of this afternoon so I'd like to check it myself now before I pay him to do additional work.

Plutoe

Post your VIN!!

Sid3ways

9A462363

Plutoe

My system requires the full VIN, repeat full VIN!!

Sid3ways

My apologies Plutoe!

4JGBF71E29A462363

Plutoe

On your MY and VIN there is no wiper relay all those functions were incorporated into the microprocessors within the front SAM.

The SAM is located under the passenger seat on the R side.

I apologies for the mis direction and corrected previous posts---I typically do nothing without a VIN!!

Sid3ways

Thank you Plutoe, maybe that is why the INDY pointed me to the SAM unit needing replaced.

When I order a new front SAM (which it appears is under the passenger seat), it says it needs programmed. Is that something that I swap out and take to the dealer (does the car even run) or do I take it to the dealer first, they program it to my VIN, then I install it? Thank you so much for all of the help!

Plutoe

Regrettably that is case---the person doing the SAM swap will first copy all the instructions from the old---place the new and flash so to speak the new SAM with the copied instructions and add any updates that may be applicable!!

Sid3ways

From what I can tell, this is the correct front SAM for my 2009 GL450. I would just purchase that and then take it to the dealer and they would put it in?

http://www.oemercedesbenzparts.com/o...enz/1649004101

I was hoping to avoid as much dealer labor as possible but if they need to uninstall my current sam to program the new one, I imagine they will charge a couple hours of labor?