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Morning,
So I have switched the SAM out to the other I bought. I purchased two while I was there and the battery is STILL dying.
I attached a digital multi-meter tp the battery and disconnect every fuse and relay from the SAM and the battery never budged.
The battery seems to be dying faster than before. I plugged it up without the negative connected for a couple hours after reconnecting it, it still had trouble cranking.
Also, I left the negative attached and with he charger on there and it still had trouble starting.
I do not mine troubleshooting, but I need some direction as to where to look.
My next option is to go through each fuse and relay in the car and see if the meter changes. I thought one of the fuses and relays in the SAM was the issue.
Can anyone assist me?
Trial and error of unplugging fuses to try to stop the drain seems like a good step
there is a workaround if you can’t find the drain and that’s to get a remote control battery disconnect , which uses a key fob to disconnect the battery every time you get out of the car so it can’t drain , you can find them on eBay
@tusabes I will for sure be buying one of those if I cannot find the drain today.
I looked up the fuse chart, but it does not look like it matches my car. I got the fuse diagram from
"fuse-box.info/mercedes-benz/mercedes-benz-cl-class-s-class-c215-w220-1999-2006-fuses-and-relay"
"knigaproavto.ru/shemy/en/mercedes/s-class/309-1998-2005-mercedes-benz-w220-and-c215-fuse-box-diagram.html"
There are a many of them either missing or misplaced on the diagram versus the car.
Cars have different options so some fuse receptacles are not used on some cars
You don’t need a fuse diagram if you are removing fuses one by one , to locate a current draw . Don’t remove them all at one time, you need to test current draw removing one by one and replacing it in the same place
I'm not sure if this has been mentioned, but https://w220.ee is a great reference for the W220s. It says the following about the rear SAM:
The rear SAMbelow the right rear seat cushion interacts directly with the trailer recognition control unit and with the ESP, SPS, BAS-controller. It communicates e.g. with the overhead control panel control unit via CAN. It also deals with all rear lights, closing the trunk and fasten seat belts indications; additionally it reads the tank level sensor, a tilt sensor (Anti-Theft Alarm inclination sensor), all 4 door contacts and the rear brakes sensors.
That site also gives information about fuses that could help you.
If you plan on keeping the car, you really should get a MB specific code reader. It will pay for itself quickly.
@tusabes That is exactly what I did. Now I am in fear that my multimeter does not have the correct setting to diagnose the problem.
I connect the "COM" to the negative post and the VmA tot he negative terminal attachment from the car. It was reading 7 throughout me pulling fuses.
This is the meter I have:
walmart.com/ip/EverStart-Value-300-Volt-Digital-LCD-Multimeter-Red-and-Black/876903
7 what? If you are reading a current draw of seven Amps, it will pull the battery down overnight. If you have the correct battery, it should have a capacity of perhaps 75 Amp/hours - that is, it should be able to supply seven Amps for over ten hours.
Your meter will read Amperage, Voltage, or resistance (Ohms). Be warned that the small meters are not capable of reading high current flows (amperage) - you can destroy the meter very easily.
Please check the battery voltage. If the battery is in good condition and fully charged, you should have 12.5 to 12.7 vdc (engine not running). With the engine running, you should have 13.2 to 13.8 vdc.
The parasitic draw on an auto battery should be in the milliamp range. Some say less than 75 milliamps, and others say less than 50. I'm not sure what a good number would be for the W220s, but with a drain overnight it will be obvious. Search for "parasitic battery drain test" for general instructions. Keep in mind that many cars will have accessories that remain on for a period after the vehicle is shut down (I've read 20 minutes). Also, opening doors will also activate accessories requiring another 20 minute wait period.
7 what? If you are reading a current draw of seven Amps, it will pull the battery down overnight. If you have the correct battery, it should have a capacity of perhaps 75 Amp/hours - that is, it should be able to supply seven Amps for over ten hours.
Your meter will read Amperage, Voltage, or resistance (Ohms). Be warned that the small meters are not capable of reading high current flows (amperage) - you can destroy the meter very easily.
Please check the battery voltage. If the battery is in good condition and fully charged, you should have 12.5 to 12.7 vdc (engine not running). With the engine running, you should have 13.2 to 13.8 vdc.
i am getting 14.0-14.1 when running and 10.1 when the key is turned twice with the motor off. That is from the reading on the hidden menu on the A/C.
Unless i am plugging the meter up incorrectly. I am getting a steady 7. I removed all the SAM fuses and i will start on the engine bay fuses tonight.
I was reading that the navigation system can have a stuck map disk that keeps the unit powered on and this significantly drains the battery. The ee.w220 site says the navigation fuse is in the driver’s side fuse box under the hood (fuse f22).
I am more and more thinking it is the battery. The volts are well to low when the key is turned twice and the electronics are on.
At work and nightly I will unplug the battery. When I plug it up the trunk lights turn on and then the pump fires up. While it is in its whine it will step down its sound like its loosing power.
Then I go to crank it and the dash goes black and it takes about 5 seconds then it'll crank.
@brooktre I will for sure pull that fuse soon to see if that is the problem.
If it is reading 10.1 volts with the key in position 2 (not cranking) then that is too low. Around 10 volts is OK for a battery when it is cranking which is what I thought you meant in post 60.
@brooktre Sorry for the confusion, but yes 10.1 without cranking with the key turned twice.
My fear is that I purchase a battery and there is still an issue that kills or makes the new battery malfunction. That is why I am trying to find the issue before hand.
Hopefully I can pull the Navigation fuse and it helps the drain.
You are trying to fly without any power. A weak battery as you describe will cause all sorts of 'errors' and will damage some electronics. Remove the battery and load test it, try a slow recharge, and if that is not successful in recovering 'load testing' good results, it must be replaced. The battery for these cars MUST be fully charged and capable of delivering cranking power without voltage dropping below 11 volts. Turning the key to the second position (car not cranking or running) should not drop the battery voltage display more than 0.5 volts. What you are describing a very weak battery. Go to an auto parts store and ask then to "load test" the battery. Leaving a battery in even a partially discharged battery overnight can and will damage it so that it will not ever again be able to deliver the high current needed for starting. What happens is this: On discharging, lead oxide reacts with the sulfuric acid and converts to lead sulfate. If not promptly converted back to lead oxide by recharging, the lead sulfate hardens and cannot be recharged ever. Leaving the discharged battery overnight will almost certainly destroy it. "Sometimes," a badly sulfated battery can be recovered by lengthy (days and even weeks long ) slow (low amperage) recharging. If the battery is not 'young' a slow charge is more unlikely to work. A 'fast recharge' attempt will often cause the very brittle lead sulfate to crack and fall off the plates and sink into the bottom or even lodge between the plates and cause a short circuit and battery explosion.
You likely have two problems - a weak battery plus a battery drain
get a new correct battery and the remote battery disconnect and you’ll have no more problems with a good battery getting drained , and you can then Take your time to find the drain cause
@kraut56 Thanks for joining us. Let me be clear. I purchased the correct battery a couple months ago. It has not been 7 months since i got it. To my knowledge it was not a "bargain one". Regardless of all that...... My fear of buying a new battery and not identifying the issue still stands. @wallyp I understand the comment, but spending the money for the battery numerous times in one year would not be wise and not something I am looking to do. I bought the correct battery, to my knowledge. The place I go to get all my batteries issues it and before whatever issue came about it worked perfectly. All of a sudden one day it died while washing it and from then on, it never recovered. @Kebowers47 All of that makes sense now. I will be sure to try and find the problem sooner than later. I should have my other car out of the shop this weekend and then should be able to get a battery next week. Now what battery do you recommend? The battery that I had was a Continental (Part# L5/H8/49CP). @tusabes That is exactly what I will do. I have been trying to get the key fuses located to see if the drain slows, but trying that on the SAM was unsuccessful. This weekend I will try and get the rest of them taken care of, to at least find what/where the draw is.
"All of a sudden one day it died while washing it and from then on, it never recovered."
You seem to feel that just because you looked at the HVAC plenum and the drain was clear, that your problem simply can't be due to water intrusion under the carpet. I suspect that you are wrong...
Did you ever pull the right-side carpet to check for wetness and corrosion?
"All of a sudden one day it died while washing it and from then on, it never recovered."
You seem to feel that just because you looked at the HVAC plenum and the drain was clear, that your problem simply can't be due to water intrusion under the carpet. I suspect that you are wrong...
Did you ever pull the right-side carpet to check for wetness and corrosion?
@wallyp Yes, I did and there was no issues there. Little by little I am learning that one issue can cause a plethora of other problems. I see and know now that the battery is a piece of the issue and there is also something draining the battery at a fast rate.
UPDATE!
So after a bit of questioning and battery testing, I think I have found out how the issue came about.
The place where I took the car cleaned the reservoir when I dropped it off to get checked out. It must have been flooded and reached the SAM since it was corroded.
So yesterday I got a new battery at lunch and kept it plugged up throughout the day.
Once getting home I tested the battery for a drain. (Correct me if I a wrong) I disconnected the negative and placed a tester on the negative terminal and negative ponytail. There was no draw.
There are still issues that have remained.
The rear shade will not go down
The doors will unlock, but will not lock
The trunk will not open
The soft close is not working
Driver seat controls/heating not working
I think the new battery and SAM fixed my issue! So THANK YOU to everyone that has helped me thus far.
Unfortunately, if there is corrosion in the rear SAM, it is virtually certain that there is also corrosion in the main power circuits under the right front passenger carpet. There will be no trace of moisture or problems in the carpet. The problem will be under the aluminum panel under the thick padding and sound-proofing under the carpet. You will probably need to remove the seat and the carpet sp you can completely dry the padding and sound-proofing, and so that you can clean and check every electrical connection in the area. Remember that these cables are hooked directly to the battery terminal, and a short circuit to ground can be catastrophic!!.
I don't remember whether or not we have gone thru this, but anyway...
Look in the right rear floor area, and find the floor lamp located behind the right rear passenger's heels. Pull the entire light unit from the rear wall - it is not necessary to unplug it, just move it out of the way.
Look at the row of exposed fuses, and find the yellow 20-Amp fuse located toward the inboard end of the row.
Remove it, wait a few seconds and put it back in. Replace the lamp unit.
This resets the control unit for the PSE (Pneumatic Service Equipment) system. If some of the stuff now works, that tells you that there was problem with that particular service. If, after a few uses, the service quits working, that tells you that there is still a problem with that service. (The PSE control system will try the service a few times, then shut it off again if there is still a problem.)
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