Really hope someone can help. Have a Mercedes 2006 GL500. After heavy snow rain and frost also a washing bowl of water over windscreen went to start my Mercedes and it wouldn’t turn over constant beeping and red message saying drive to workshop without changing gear also srs restraint system message. The beeping does not go off even with car locked. Unable to select gears indicators do not work time clock spins around like crazy then finds correct time! Have changed to brand new battery still the same issue Unless I disconnect battery beeping does not go off and you cannot crank vehicle. Unable to connect to ecu obd port has power but can’t communicate with ecu. Can anyone help it’s stuck on my drive 😫. Also indicators don’t work.I have an advanced scan tool which has managed to gather a number of codes which I have attached below. Thank you to anyone that could help.

 

This platform is known for leaking taillamp gaskets, allowing water to leak and damage electrical components. Look at your tail lamps and remove everything from the spare tire well to look for water.

 

An update on my issue with my GL500. I have removed n/s and o/s rear panels also removed spare wheel and carpet around spare wheel area under carpet is bone dry no water at all. N/s and o/s panels signs of water but just in white sponges especially underneath o/s Sam unit however Sam unit I have removed and this seems dry the water around contacts and no visual water around plastic. I have gone into detail as what’s working in car these things are electric windows and seats, central locking and dipped lights, interior lights excluding glovebox, tailgate and folding mirrors, audio system and rear dvd system, 3rd row electric seats, ignition sounds like fuel pump is working. Here is what is not working, horn, main beam, indicators, time clock spins then finds correct time, steering wheel buttons. I am desperate for help even if it’s just to get it started to get to a garage. Any help would be greatly appreciated. Would anyone recommend taking out rear o/s Sam even though it does not appear wet? Also would a rear Sam cause these problems?

 

Have you investigated the area under the front passenger seat for water intrusion?

 

I think OP needs to chime in on what passenger and driver side is for him.

Supposedly this is a ‘06 GL500, which is something the Rest Of the World never got.

could be a right hand drive vehicle which would explain water coming in from the cabin air filter and under the front left seat.

 

Hey guys thanks for your help and yes sorry I should of mentioned it is a rhd vehicle.
The carpet under the passenger seat seems dry but I am unsure of the Sam location is that under carpet level or is it directly under seat? There are identical boxes under both driver and passenger seats but I think they are can bus units. I will lift carpet in that area and inspect further today thanks very much for your help.

Update
So you guys have given me hope I have removed carpet just in front of passenger side seat shone a torch through metalwork to base of floor and I can see at least an inch of water. I can’t see Sam unit but I’m guessing I need to remove seat to remove carpet and access lower floor is this correct and how easy to does seat come out. I just wanted to confirm that my GL500 is a right hand drive uk car. Can you confirm exactly where Sam unit is and how to access before I remove passenger seat. Thanks so much I’m super grateful for this help.👍

 

You can find the front SAM unit under the seat of the right side of your car, in this case the driver's seat. If you are unable to move the seat all to front and up using it's controls, you need to remove it. Do not turn the ignition on during this procedure as the first thing that is going to happen, is the air bag light going on. Under the seat you will find the car battery and the auxiliary battery (that is not easy to remove). If you find water there, there is a big chance that the SAM is in short circuit, and maybe, a cleaning with isopropil alcohol and letting it dry is one possible solution. If this does not work, the cancer to recover it are very low.
The other SAM module that can be bad is the one found at the engine bay, on the right side of the car. It is a black box with a lot of fuses inside it.
I hope you can find a solution for you problem.

 

Thanks for the reply on my issue with the water leak I will check those points mentioned. I am slightly confused tho as an earlier post suggests the front Sam unit is on n/s of vehicle under passenger floor not on drivers side as you mentioned. Could somebody confirm before I take the passenger seat out as to the exact location of the front Sam on my 2006 gl500 uk car right hand drive. All of the water appears to be on the left side not on drivers. Thanks in advance.

 

So we’ve at least found water under the passenger seat, which points towards that the cabin air filter box may be clogged and water is coming in that way. On a rhd vehicle the firewall layout is mirrored, so the cabin air filter box should be on the passenger side I believe.

Whether or not the layout of modules and batteries is mirrored in a rhd drive vehicle I do not know, but odds are that where the water is is where you have the electrical problem.

you know the old saying - where there is water, there isn’t fire.

it is possible to access use both seats by running them full forward and up and not have to take them out, but removal is also fairly simple with four e-torx bolts holding the rails down.

just don’t switch on the ignition with the seats disconnected as you’ll trigger an SRS fault.

 

thanks for your advice

update

Ok so the plot thickens I have managed to locate the front Sam which is just next to the auxiliary battery on drivers side right hand side of car it is dry and no sign of water damage as mentioned the right hand side of vehicle floor is dry. With the n/s floor having water in I decided to remove the n/s seat and investigate floor base for any electronics that may have water in them now here’s the problem with the seat removed to access the base of floor the whole carpet on n/s of vehicle needs to come out on top of this there is a series of plastic venting for blowers with very small clips from shining my torch through gap in carpet and plastic ducting the only electric modules/boxes are clear of the water. So I wanted to know if anybody has experience of taking the carpet and plastic trim out I think this may be beyond me and I’m wondering if there is a drain in floor area that I can access instead from underneath. I will attempt removing all trims and investigating further but Is it likely that anything of any significance will be under there causing the problem with the Sam unit being on the right hand side. I have checked the cabin filter box and there is no water pooling, the cabin filter box is on the left side the same side as the water intrusion. Any further help would be greatly appreciated 🙏

 

I’m sorry can you translate n/s and o/s into left and right please.

you may also want to check your sunroof drainsZ

while you’re looking for water , also look in the rear spare tire compartment.

 

Hi sorry n/s being passenger side and o/s being drivers. Thanks

 

*Dramatic Update*

So passenger seat and carpet removed to a point passenger side inspected can’t get to bottom of floor due to heater ducting appears to be a thin layer of water directly under seat but any control until I can see is well above that point unless I drill a hole in floor then I can’t get to it. I’m going to try and syringe it out. Battery removed on drivers side no visual signs of any water also checked Sam unit completely dry and auxiliary battery seems ok. Checked under bonnet whilst cabin filter (passenger side) appears dry the drain at bottom was completely blocked so I’m guessing that’s how the water has got under passenger seat. Fuse box on passenger side of dash ok and one under bonnet drivers side looks ok no fuses blown. So all doors been open all day an unusually warm February day 14 degrees battery reconnected noticed drive to workshop beeping had gone intermittent and then after about 1 min disappeared with just srs and a new tyre warning unavailable appeared steering wheel buttons then started working quickly plugged scanner into obd and it connected to ecu for first time I have attached fault codes direct from obd reading ecu previously it wouldn’t connect to ecu. Noticed battery was low due to car being worked on all day waited for battery to charge then to my amazement she fires up. I’ve got no idea what I did to rectify this or if it was simply the better weather my merc has been beeping at me none stop for a week stuck on my drive unable to move. My question is is it worth taking the risk to drive and what do you guys think cured it? I’ve attached picture of ecu codes. One other question my nav has lost its antenna reception could this be located under seat or n/s footwell under carpet as I’ve been around this area. Look forward to your comments and thanks for the help fingers crossed it gets me to a garage. 🙏

 

 

Read this


https://www.youcanic.com/guide/merce...nging-gear-ism

 

Take a look at the front SAM module (fuse box) at the engine bay. Maybe the connectors are dirty or corroded.

 

Hey thanks for the replies that’s a great article about the ism module but I have read fault codes on ism it has no codes and no history of any code.

One thing I wanted to ask is when I do a full automatic scan of the car with my advanced scanner it comes back with around 24 dtc codes then once cleared it leaves around 12 stored codes with anyone’s experience on owning a 14 year old Mercedes GL or ML is that normal or have I got a can of worms coming? Another question I need to know is the gps reception bars next to the TA at bottom right of command unit are hollow and I have a feeling before I stripped Mercedes to look for leak that these filled up in a permanent white colour depending on gps reception is this correct or do they just stay a hollow colour I will attach picture to show what I mean shortly. Thanks 🙏

 

Something that is common with Mercedes is that, when the auxiliary battery is near the end of it's life, is to throw DTC codes that are not related. The most common codes that are frequently in this situation are those related to the dashboard communication, front seats, rear seats, rear SAM, DVD player overheating (even if it is not working). Of course, the codes that are shown can be different according to the scan tool that you are using. In my case, I use the Star Diagnosis C4 with the software updated in 2014.
Another point to be alert, when the ISM is faulty, it is impossible to engage any gear and the only way to test it is using the Star diagnosis. Unless the ISM has had a short circuit, sometimes it does not shows DTC codes, and has to be tested with Star Diagnosis, were it is possible to switch gears using the computer software.
When my GL500 had a problem like yours, the faulty part was the voltage regulator attached to the alternator and even using Star Diagnosis, the DTC codes that were shown were not related to it. The codes were related to the ECU and the anti theft system that was blocking the signal sent to the relay that controls the start motor and another one that enables the ECU to send energy to the coils. I just discovered this one year after the issue appeared.

 

If this water intrusion episode was a one time deal, and you’ve fixed the leak and dried all wet parts out and sustained no corrosion in the electrics, you shouldn’t have any Current codes (capital F - Stored codes read as a lowercase f in a star quick test.)

I have a number of them from momentary events such as last week when the battery voltage went really low one cold morning, and also a current CEL. I haven’t checked into any of them because the car drives and runs just fine.

bottom line - it’ll throw codes at you every now and then, but if they persist or manifest themselves in tangible issues (won’t start, lights flashing etc) only then do you need to go look and see what’s going on. Otherwise you’re just chasing garbage codes.

your gps bars should fill in but the positioning of the vehicle may preclude reception, the antenna may be have gotten unplugged or you still have water damage to that unit or it’s input connector to the Comand system.

 

Thanks machadosl & max blast for taking the time to reply and help with my GL very interesting and valid points I’m hoping the cause of leak was from the cabin filter drain but not 100% sure I’m going to keep an eye on the floor and check to see if any further water ingress accumulates. It doesn’t look like a hard job to replace the auxiliary battery so I might just change this just to eliminate if it’s disconnected would I need a code for the command system or is it linked to the vehicle ? An interesting point about the ISM module a technical question on that is if I was to have the same issue again I.e car won’t start drive to workshop without changing gear could the Star diagnosis scanner get the vehicle started if it is the ism by getting it to select gear? Thanks again for the helpful feedback👍

 

Well, when you remove the auxiliary battery most of the time you have reprogram one touch opening and closing of all windows and solar roof, nothing more need to be reprogramed.
About the ISM, if it is an intermittent malfunction, with Star you can enable the car to get started, but if it has a serious problem like a short circuit inside of it or the electrical motor that moves the gear, it won't help.
Sometimes the car also does not start due to a fault in some of the relays located in the fuse box (front SAM) at the engine bay.
As far as I know, there isn't a relay for ISM in the car, only a fuse (3A fuse 111 at the fuse box in the engine bay).

 

Hey machodosl,


Great information that’s appreciated I’ll give all that some thought I really don’t want to get rid of it as it’s such a great car (warts ‘n’ all) just don’t want things getting unreliable. With the gps aerial I will check passenger seat connections as have had whole seat out of vehicle. Thanks again.