2008 S550 Electrical Gremlins? New Owner
12-30-2018, 09:41 PM
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2008 S550
2008 S550 Electrical Gremlins? New Owner
Hello Everybody,
A few months ago I drove one of our friends cars (2008 S550) and was enamored with it. For some reason my wife decided to purchase it for me for Christmas and I’ve noticed a few things I have questions about.
I apologize in advance for the large text block. I’ve extensively searched the forums and decided to register/start a new thread. Any and all advice is appreciated.
Keyless-Go: When I drove it a few months ago there was an issue with the push to start. If you started the car and shut it off with the push button, the lights and screen would stay on for 30-60 minutes and you weren’t able to lock the car by remote. For a short term fix I used the physical key by removing the push button and it would shut off correctly and allow you to luck unlock with the fob. I reset the Comand (by holding the cd eject buttonand it worked for a few days then started acting up intermittently. If you use the physical key to start the car the lock unlock functions work flawlessly 100% of the time.
Seats: Sometimes the seats will work (lumbar, shoulder, side bolsters, seat bolsters) and sometimes when I make a change in Comand it will instantly revert back to 0. This is for both drivers and passengers. When they work they both work and when they don’t they both don’t. I’ve noticed no correlation between when Keyless Go works correctly and when it doesn’t, it seems to be completely random. Dynamic seats will sometimes work (for about 10 minutes) and sometimes immediately revert back to 0 when setting them.
The auxiliary battery was replaced a few months ago but it was the previous owners 4th car. It was driven very sporadically and would sit for weeks at a time. I’ve considered this to be a possibility.
Is is there anything else I should be looking at or focusing in on?
In addition to the electrical there’s also a slight clunk coming from the rear passenger and it seems the car skips laterally over large bumps. I’m dropping it off at an Indy tomorrow morning to have the suspension looked at and any worn components replaces. Is there anything I should be ask them to check?
I appreciate anything the community suggests and thank you in advance.
Best Regards,
Nathan
A few months ago I drove one of our friends cars (2008 S550) and was enamored with it. For some reason my wife decided to purchase it for me for Christmas and I’ve noticed a few things I have questions about.
I apologize in advance for the large text block. I’ve extensively searched the forums and decided to register/start a new thread. Any and all advice is appreciated.
Keyless-Go: When I drove it a few months ago there was an issue with the push to start. If you started the car and shut it off with the push button, the lights and screen would stay on for 30-60 minutes and you weren’t able to lock the car by remote. For a short term fix I used the physical key by removing the push button and it would shut off correctly and allow you to luck unlock with the fob. I reset the Comand (by holding the cd eject buttonand it worked for a few days then started acting up intermittently. If you use the physical key to start the car the lock unlock functions work flawlessly 100% of the time.
Seats: Sometimes the seats will work (lumbar, shoulder, side bolsters, seat bolsters) and sometimes when I make a change in Comand it will instantly revert back to 0. This is for both drivers and passengers. When they work they both work and when they don’t they both don’t. I’ve noticed no correlation between when Keyless Go works correctly and when it doesn’t, it seems to be completely random. Dynamic seats will sometimes work (for about 10 minutes) and sometimes immediately revert back to 0 when setting them.
The auxiliary battery was replaced a few months ago but it was the previous owners 4th car. It was driven very sporadically and would sit for weeks at a time. I’ve considered this to be a possibility.
Is is there anything else I should be looking at or focusing in on?
In addition to the electrical there’s also a slight clunk coming from the rear passenger and it seems the car skips laterally over large bumps. I’m dropping it off at an Indy tomorrow morning to have the suspension looked at and any worn components replaces. Is there anything I should be ask them to check?
I appreciate anything the community suggests and thank you in advance.
Best Regards,
Nathan
12-31-2018, 12:30 AM
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'15 S550, '10 E350 P1/P2, '02 ML320
Hi Nathan! Congrats on your new W221! I would scan for codes first, it could be that pesky battery (mine had to be replaced this fall after 7 years.)
12-31-2018, 09:36 AM
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12-31-2018, 10:50 PM
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Hello Everybody,
A few months ago I drove one of our friends cars (2008 S550) and was enamored with it. For some reason my wife decided to purchase it for me for Christmas and I’ve noticed a few things I have questions about.
I apologize in advance for the large text block. I’ve extensively searched the forums and decided to register/start a new thread. Any and all advice is appreciated.
Keyless-Go: When I drove it a few months ago there was an issue with the push to start. If you started the car and shut it off with the push button, the lights and screen would stay on for 30-60 minutes and you weren’t able to lock the car by remote. For a short term fix I used the physical key by removing the push button and it would shut off correctly and allow you to luck unlock with the fob. I reset the Comand (by holding the cd eject buttonand it worked for a few days then started acting up intermittently. If you use the physical key to start the car the lock unlock functions work flawlessly 100% of the time.
A few months ago I drove one of our friends cars (2008 S550) and was enamored with it. For some reason my wife decided to purchase it for me for Christmas and I’ve noticed a few things I have questions about.
I apologize in advance for the large text block. I’ve extensively searched the forums and decided to register/start a new thread. Any and all advice is appreciated.
Keyless-Go: When I drove it a few months ago there was an issue with the push to start. If you started the car and shut it off with the push button, the lights and screen would stay on for 30-60 minutes and you weren’t able to lock the car by remote. For a short term fix I used the physical key by removing the push button and it would shut off correctly and allow you to luck unlock with the fob. I reset the Comand (by holding the cd eject buttonand it worked for a few days then started acting up intermittently. If you use the physical key to start the car the lock unlock functions work flawlessly 100% of the time.
I would ensure the EIS that the Keyless-Go button is inserted into had no debris on the IR sensor, and check that the spring-loaded part where the KG/SmartKey is inserted can easily be pressed with your little finger down (mimicking what the Keyless-Go button does when you press it or use the SmartKey) and it returns to the surface when pressure is released. You can test another Keyless-Go button from another car and see if it makes a difference. The buttons are not unique.
Seats: Sometimes the seats will work (lumbar, shoulder, side bolsters, seat bolsters) and sometimes when I make a change in Comand it will instantly revert back to 0. This is for both drivers and passengers. When they work they both work and when they don’t they both don’t. I’ve noticed no correlation between when Keyless Go works correctly and when it doesn’t, it seems to be completely random. Dynamic seats will sometimes work (for about 10 minutes) and sometimes immediately revert back to 0 when setting them.
The auxiliary battery was replaced a few months ago but it was the previous owners 4th car. It was driven very sporadically and would sit for weeks at a time. I’ve considered this to be a possibility.
Is is there anything else I should be looking at or focusing in on?
Is is there anything else I should be looking at or focusing in on?
In addition to the electrical there’s also a slight clunk coming from the rear passenger and it seems the car skips laterally over large bumps. I’m dropping it off at an Indy tomorrow morning to have the suspension looked at and any worn components replaces. Is there anything I should be ask them to check?
I appreciate anything the community suggests and thank you in advance.
Best Regards,
Nathan
Best Regards,
Nathan
01-01-2019, 07:56 AM
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2008 S550
I would ensure the EIS that the Keyless-Go button is inserted into had no debris on the IR sensor, and check that the spring-loaded part where the KG/SmartKey is inserted can easily be pressed with your little finger down (mimicking what the Keyless-Go button does when you press it or use the SmartKey) and it returns to the surface when pressure is released. You can test another Keyless-Go button from another car and see if it makes a difference. The buttons are not unique.
Sounds like you have a leak in the pneumatic system or the pneumatic pumps is overheating and shutting off. You will need to use a Star Diagnostics unit to read out fault codes and it can also test the system for leaks. A dealer can do this for you if the independent does not have Star Diagnostics (you would be surprised how many don't).
The batteries are confusing for those not familiar with them, and many get the terms crossed up for them. We can keep it easy and refer to them as the front (small, lawnmower-size Starter battery) and rear (Consumer battery, used for every thing except Starting - very large and difficult to remove depending if you can crawl in and out of the trunk easily). The issue is that when the rear battery has reached the end of its useful life, unless you have it tested or know what to look for, you will have no idea as most people replace their batteries when the starter begins to crank slow. Since the rear battery is typically not involved in this operation, you would have no clue. There is one tell-tell sign to look for - open the driver door and get in the vehicle without turning anything on and observe how quickly the interior lights turn off (with your door still open). Or, alternatively, use the COMAND listening to music and as the voltage drops it will display "Start Engine or COMAND will shut down in 3 minutes." If this comes on after playing a CD or radio, or watching a movie in 5 minutes or less, you need a battery. Things you may not notice that the ECUs in the vehicle are setting "undervoltage" fault codes, and the car can misbehave (cause what you are seeing with the Dynamic Seats for example) and other odd issues. Not to mention it will shorten the life of your alternator.
Good idea.
No problem.
Sounds like you have a leak in the pneumatic system or the pneumatic pumps is overheating and shutting off. You will need to use a Star Diagnostics unit to read out fault codes and it can also test the system for leaks. A dealer can do this for you if the independent does not have Star Diagnostics (you would be surprised how many don't).
The batteries are confusing for those not familiar with them, and many get the terms crossed up for them. We can keep it easy and refer to them as the front (small, lawnmower-size Starter battery) and rear (Consumer battery, used for every thing except Starting - very large and difficult to remove depending if you can crawl in and out of the trunk easily). The issue is that when the rear battery has reached the end of its useful life, unless you have it tested or know what to look for, you will have no idea as most people replace their batteries when the starter begins to crank slow. Since the rear battery is typically not involved in this operation, you would have no clue. There is one tell-tell sign to look for - open the driver door and get in the vehicle without turning anything on and observe how quickly the interior lights turn off (with your door still open). Or, alternatively, use the COMAND listening to music and as the voltage drops it will display "Start Engine or COMAND will shut down in 3 minutes." If this comes on after playing a CD or radio, or watching a movie in 5 minutes or less, you need a battery. Things you may not notice that the ECUs in the vehicle are setting "undervoltage" fault codes, and the car can misbehave (cause what you are seeing with the Dynamic Seats for example) and other odd issues. Not to mention it will shorten the life of your alternator.
Good idea.
No problem.
Polar Bear,
I really appreciate all the time you've spent helping me along with this diagnosis. Some of the items you've touch on are absolutely correct after taking the car in yesterday. I believe the shop to be highly competent and they spent 2.5 hours going entirely through the car as if it as a pre-purchase inspection. No fault codes popped up.
Keyless-Go: is extremely sporadic and didn't act up while in their possession. I'll try that with the other key I have and see if anything comes of it. For the time now I'll leave it be as inserting it manually fixes the issue.
The Seats: You nailed it. There are some leaks and while they weren't able to determine the exact location (I'm assuming they don't actually have the star program based on your info) I can feel the seat bolsters and left side upright bolster deflate. I've searched the forums and will
Rear Battery: Voltage tested okay and everything checks out. I'll probably hold off as none of the symptoms you've suggested have appeared. If they do it's one of the first things I'll have done.
Additional Question: My main focus was the suspension as it rides pretty rough with pretty noticeable clunking in the rear. While cornering at speed on on on-ramp, if you hit a bump it seems as if the car "loses traction" or shifts in the rear end. The struts and all other components were in perfectly fine shape (not leaking, no codes, etc.) but they did note the age and recommend replacement at some point in the future. It's something I'd like to change myself with some supervision but would that cause the shifting of the body in the rear? I've searched the forums and a rear subframe mount looks to be a likely cause but none of the other symptoms that are attributed to a rear subframe mount are prevalent. No clunking when shifting from reverse to drive etc. Should I replace the struts proactively? I have a hard time believing this is how the car is supposed to ride.
A huge thank you to the forum and everyone who has helped. This community is extremely fantastic.
Best Regards,
Nathan
