Water under drivers seat with various electrical problems
Thread Starter
Newbie
Joined: Sep 2011
Posts: 4
Likes: 0
GL 420 Cdi
Water under drivers seat with various electrical problems
Hi guys,
After a huge downpour of rain I found the drivers footwell 50mm deep in water and the battery was flat. I jumped the car and the back windows went down on their own. Low range and diff locks won’t work at all (no light on button) and when parked the car continually raises the suspension then lowers causing the battery to go flat by the next day.
Bit random. Any help would be much appreciated.
After a huge downpour of rain I found the drivers footwell 50mm deep in water and the battery was flat. I jumped the car and the back windows went down on their own. Low range and diff locks won’t work at all (no light on button) and when parked the car continually raises the suspension then lowers causing the battery to go flat by the next day.
Bit random. Any help would be much appreciated.
Last edited by JaBlonde; Jun 3, 2021 at 06:27 PM.
Super Member
Joined: Apr 2004
Posts: 625
Likes: 82
From: Germantown, MD
'07 GL450
Check for water intrusion in the spare tire area, and inspect the rear SAM module.
There are a few threads on this forum regarding the gremlins that pop up when the rear SAM gets wet. A quick google/youtube search is sure to turn up a few good videos to aid you in isolating the source of the water intrusion.
There are a few threads on this forum regarding the gremlins that pop up when the rear SAM gets wet. A quick google/youtube search is sure to turn up a few good videos to aid you in isolating the source of the water intrusion.
Thread Starter
Newbie
Joined: Sep 2011
Posts: 4
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GL 420 Cdi
Thanks for replying so quick. I have pulled the carpet up and had a good look in the rear right side and it is all bone dry and factory clean. Under the sub woofer is all dry as well (I can't see the unit under the sub properly - is that the rear SAM module?)
I spent 5-6 hours over the last few days googling and watching videos, but other than checking/ swapping out the SAM modules, people have had different electrical issues to the ones I am experiencing.
I spent 5-6 hours over the last few days googling and watching videos, but other than checking/ swapping out the SAM modules, people have had different electrical issues to the ones I am experiencing.
Last edited by JaBlonde; Jun 5, 2021 at 04:26 PM.
MBWorld Fanatic!
Joined: Jan 2010
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NGL450 w/EORP, S550
Under both front seats are wells housing batteries and sensitive electronics.
first: remove as much of the floor paneling as you can and get some driers/dehumidifiers in there after you have wetvac’ed up all the water. time is money here.
If the problem is isolated to the front the first thing you need to check is the cabin air filter box drain on the passenger side firewall.
Then check the sunroof drains and blow them out with compressed air as needed.
first: remove as much of the floor paneling as you can and get some driers/dehumidifiers in there after you have wetvac’ed up all the water. time is money here.
If the problem is isolated to the front the first thing you need to check is the cabin air filter box drain on the passenger side firewall.
Then check the sunroof drains and blow them out with compressed air as needed.
Thread Starter
Newbie
Joined: Sep 2011
Posts: 4
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GL 420 Cdi
Thanks for your help Max. Do you know what ECU's or control units are in the battery bay, the chamber under the drivers seat on a GL450 UK? I can't find any diagrams or other information online.
MBWorld Fanatic!
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NGL450 w/EORP, S550
in that bay lives your battery bus, the main and aux batteries, and off the top of my head a few relays.
Water here will short out the power path and leave everything else downstream malfunctioning.
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Newbie
Joined: Mar 2023
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gl x164
Hi,
I have the same symptoms with my GL 2008, after some water damages, the rear windows went down by themselves and some other items started to behave strangely like the horn, the wipers, ....
My car cranks up but even though the screan shows D (drive) position, the gears do not shift and the car does not move when giving gases.
I dont't know if you solved your issue in the meantime but it would be nice to share what were the issues.
Thanks in advance.
I have the same symptoms with my GL 2008, after some water damages, the rear windows went down by themselves and some other items started to behave strangely like the horn, the wipers, ....
My car cranks up but even though the screan shows D (drive) position, the gears do not shift and the car does not move when giving gases.
I dont't know if you solved your issue in the meantime but it would be nice to share what were the issues.
Thanks in advance.
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Thread Starter
Newbie
Joined: Sep 2011
Posts: 4
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GL 420 Cdi
After spending £1,500 for a mechanic to investigate the issues with no improvement to the situation, I passed the problem to my insurers and they wrote off the vehicle in the end. You can take out the ECU's and have someone repair them but ultimately you don't know what further damage the wiring shorts have done to everything else in the car. Sorry I can't be of more help.
MBWorld Fanatic!
Joined: Jan 2010
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NGL450 w/EORP, S550
Water intrusion and electrical malfunctions in a 15 year old GL equals insurance write off.
This isnt isolated to GL platform, following the kid on YouTube right now who bought a 2011 S class that had been totaled as a flood vehicle because the insurance company wrote it off after the cabin air filter drain had clogged and doused one ECU with water…
This isnt isolated to GL platform, following the kid on YouTube right now who bought a 2011 S class that had been totaled as a flood vehicle because the insurance company wrote it off after the cabin air filter drain had clogged and doused one ECU with water…
Member
Joined: Mar 2023
Posts: 119
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GL320 X164 OM642 722.902
Water intrusion and electrical malfunctions in a 15 year old GL equals insurance write off.
This isnt isolated to GL platform, following the kid on YouTube right now who bought a 2011 S class that had been totaled as a flood vehicle because the insurance company wrote it off after the cabin air filter drain had clogged and doused one ECU with water…
This isnt isolated to GL platform, following the kid on YouTube right now who bought a 2011 S class that had been totaled as a flood vehicle because the insurance company wrote it off after the cabin air filter drain had clogged and doused one ECU with water…
I noticed some moulds on the seatbelts (same side, both row) and wondering how it got there. I opened the floor panel and the pillar. Washed my w164 with a garden hose. Did not notice any wet or damp spots. The sunroof was leaking though. But the sunroof has a drain towards somewhere. Still can't find a satisfactory reason how the mould was there.
On another note, the w164 has a water drain somewhere close to the driveshaft. This might be the drain for the battery compartment. I might take a picture when I have a chance. There is a plug beside the water drain and touched the insulation inside for moisture. Was dry and clean (no moulds). Still wondering how water was present in that drain. If it was droplets then i can understand. But it was dripping at a faster rate and created a puddle.
MBWorld Fanatic!
Joined: Jun 2010
Posts: 2,762
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From: Emmett, ID, USA
2007 GL450
Water intrusion and electrical malfunctions in a 15 year old GL equals insurance write off.
This isnt isolated to GL platform, following the kid on YouTube right now who bought a 2011 S class that had been totaled as a flood vehicle because the insurance company wrote it off after the cabin air filter drain had clogged and doused one ECU with water…
This isnt isolated to GL platform, following the kid on YouTube right now who bought a 2011 S class that had been totaled as a flood vehicle because the insurance company wrote it off after the cabin air filter drain had clogged and doused one ECU with water…
"Insurance write offs" is probably why my comprehensive insurance got so absurdly expensive. A bird poops on it, insurance company pays out several years worth of premiums.
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NGL450 w/EORP, S550
Hook your peepers onto Waldo’s world YouTube channel - guy got a “flooded” S (w221?? I don’t know my Sses) for a song, only to find that the airmatic module was the only thing damaged by a plugged cabin air filter drain.
however; it required a parts car to get running economically again, which is not everyone’s ability.
that’s why my Gl will become a parts car for a future x164 550. Or the other way around, since I’m liking that 550 build thread so much.
however; it required a parts car to get running economically again, which is not everyone’s ability.
that’s why my Gl will become a parts car for a future x164 550. Or the other way around, since I’m liking that 550 build thread so much.
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Old tread, I get it
Wet **** under the seats, floorboards,etc. is never fun on Mercedes. Amazon sells cheap wifi enabled water alarms, battery live 5+ years. There are five in my current project. W164.
Drivers side under well, passenger side under well, rear sam, under spare, and one mounted underneath that will tell me if water might come over the door sills.
Drivers side under well, passenger side under well, rear sam, under spare, and one mounted underneath that will tell me if water might come over the door sills.
