When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Got an S430 with a few problems. The previous owner took it to the dealership for repairs and, based on what they found, decided to get rid of it. The only thing that isn't working is the doors and trunk will not lock, unlock, or open with the key fob. I know the fobs are good...one is brand new...because the lights flash on the car when I push the button. I did have to replace the battery when I got it but have gone through the key programming twice and synced the windows and seats. I have checked the F62 fuse that drives all of it (and the rear seat headrests which also don't work) and the fuse is ok. I can put my hand on the component in the driver's side trunk well (which I believe is a vacuum pump since it has a bunch of small air lines connected to it) and the pump at the trunk door latch. I can feel a click when I push the unlock button on the fob. After reading on it, I feel like it is driven pneumatically. It feels like the relays and solenoids (if that is how the system works) are shifting since I feel the click but nothing is happening. Don't know where the air supply for this system comes from (is there a second pump?) but the suspension is working. I can hear the pump come on when the suspension is adjusted. So, that is where I am, but on to my question. When I got the car, there was a large metal plate with a piece of styrofoam laying in the back seat. We had no clue where it might go but oddly enough, I was watching a video on how to change the cabin air filters and saw it in the video. It is in the foot well on the front passengers side. When wondering why it was removed, I looked in there and see a box with red wires connected but no ground. Also has a couple of plugs. Can anyone tell me what this box is and what it does? I am wondering if it has something to do with the door lock issue???
That is one of the primary fuse complexes. There are several fuses and connections in the area. Use extreme caution - the connections are directly hooked to the battery positive - a short circuit here can cause severe damage, up to and including burning the car to the ground.
You may have some serious problems. One of the known issues with the W220 is that the drain in the HVAC plenum can easily become plugged from leaves and debris. Then the plenum fills with water, which spills over inside the car, running under the carpet. There will be no visible water - it will be under the carpet! The connections in the photo become corroded, with subsequent electrical problems. Even worse, the water will run in the stamped floor channels to the rear seat area, entering the rear SAM (Signal Acquisition Module), the fuse/relay/computer box under the right side of the rear seat. Corrosion and water damage here will cause numerous problems on the rear of the car - including with the PSE (Pneumatic Service Equipment) air pressure/vacuum pump in the trunk.
At this point, you probably need to disconnect the battery, then disassemble, clean and test all of the connections and fuses in the underfloor area. Then you will need to remove and thoroughly dry all of the carpet, the padding and the insulation on the right side of the car. It will take a few days for this stuff to dry after it is removed from the car, which will require the removal of the passenger seat.
Then, you will need to remove the rear seat bottom (there is a release on each front corner at the bottom). The SAM is the black box on the right side. The SAM must be thoroughly dried, and all corrosion removed, which is not a simple task.
Now you know why the previous owner sold the car...
Here are the primary reference sources to get you started.
Thanks Wally! The car sat for 8 months so I think the water would have dried by now but I will open the panel and see if there is corrosion. Is there a fuse in this block that would affect the F62 fuse circuit that controls door locks, trunk lid, and back headrests? Also, do you know where a guy might find a wiring diagram? Can't seem to find one online and it sure would help in tracing the circuit!
The water may be gone, but the corrosion may well remain...
Look in the right rear floor area, and find the light that is behind the passenger's heels. Pry the top out and remove the light fixture - no need to unplug it. Look in the opening, and find the yellow 20-Amp fuse near the inboard end. Pull it out and check it. Replace it, and see if the locks and headrests work now.
On some cars, the headrest power up and down, on many cars, you lift the headrests manually, and they drop when you push the dash button.
Your door lock /trunk lock /headrest problem is the PSE air pump in the trunk . These are all controlled by this pneumatic pump .
The airmatic pump for the suspension is a totally different pump in the front of the car .
The main fuse box on the passenger floorboard is a totally different system . That part was likely exposed to jump start the car when they couldn’t open the trunk as it’s the only point to jump start the car besides the trunk
Thanks a ton for taking the time to help a fella out!
tusabes, I was considering the pump in the trunk as it was the only part, other than the fuse wallyp suggested I check (I did, it looked good but I replaced it anyway and no luck), that was common to all of the components currently not working.
Looks like I will go online and see if there is a way to check the pump...if you guys have any suggestions, you know they would be greatly appreciated.
At this point, I considered buying a new one and just change it out but for what they cost, I believe I will try to confirm it is bad first...
It’s not that simple . The pump may have stopped to protect itself . by pulling out the 20amp fuse , it should reset it and some functions should work . It’s not checking to see if the fuse is bad it’s to reset the pump
If no air functions worked when you reset the pump by pulling the fuse then it probably is a bad pump
plue irs not as simple as buying a new or used pump . They need to be programmed to your car
08-06-2019, 07:55 AM
