Mercedes-Benz Forum banner

Starting issue after running

1K views 6 replies 6 participants last post by  quicksilver98 
#1 ·
Car starts and runs great. However after operating for 20 mins or so and shutting it off and then restarting right away it acts like a dead battery and doesn't turn over. But it you wait 10 mins or so it will fire right up. Any idea what the problem might be on this 2009 SL 550 with 20000 miles on it.
 
#4 ·
how can a fuel pump stop an engine from rotating and cranking?
 
#5 ·
Check your starter, check the condition of both front and rear batteries, and also, find out if you have any BNC codes, as BNC is responsible for bringing batteries on and off line, if one or the other is dead.
 
#6 ·
I know that this seems counter-intuitive but I had the exact same issue on my car.... Turns out the starter battery was bad. I know that it doesn't make sense but when the car had been sitting and cooled off it would start, a hot start would cause it to act like a drained battery.

Have the battery tested, most auto parts shops around here will test if for free.

If you need to replace it.... I had to go to the last place that I wanted to, the dealer. I could not find a replacement that would fit for any less cost than them! Was about $180+/-

Cheers
 
#7 ·
I had the same thing happen just this summer on my 06 SL500 and it turned out to be a 8 dollar relay on the passenger side under the hood. I think it was called K40-40K or 40L One of them is for the starter relay and the other is for engine electronics. I would check both of them. If the one for engine electronics goes bad then your ECU is dead to the point where it wont even communicate with your SDS if you tried to read a error codes. Not sure if the SL550 has the same relay/fuse layout as the SL500. You will need to check your owners manual. Good luck. Autozone or any auto part store carries those relays. (By the way mine did as you described 2 or 3 times then eventually died where it would not start at all)
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top