E Coupe (C207) Hold/StopStart problems
- Thread starter colh107
- Start date
Started fine on Saturday after a couple of days, though only took a short trip to the shops - then a bit sluggish to start today. With an ABS/ESP warning flashing up.
Going to get battery Pro-checked tomorrow (hopefully the aux too).
Other weird things that have been happening (only a few times a month) since summer:
Going to get battery Pro-checked tomorrow (hopefully the aux too).
Other weird things that have been happening (only a few times a month) since summer:
- Seat belt 'helper' extender not extending when I start the car. [Ok on the manual button a few secs later]
- COMAND switches by itself from Radio to Disc, 5 secs or so after starting
I am one these owners that have disconnected the battery sensor (always turned stop/start off), regarding brake hold, I didn`t know I had it for the first 18 months, I don`t trust it so don`t miss it, stop/start is not for me as I have to enter into a fast moving traffic flow from a side road every morning, it also halves the life the battery, that said.
There are I believe 3 systems linked to the battery sensor attached to the starter battery, auto stop/start, brake hold and energy regeneration. The sensor is there to monitor the state of charge of the battery (SOC), this is to ensure (1) there is enough charge in the battery to be able to restart the car after it has been stopped by the auto system (2) there is enough room in the battery for any high voltage regenerating, this means the starter battery`s SOC can be as low as 75% at any time, (3) there is enough energy in the battery to enable brake hold.
To test the battery the car has to rest overnight to allow any surface charge on the plates to dissipate otherwise a false high reading is observed, a fully charged battery should read 12.7/8 volts, after resting overnight release the bonnet and boot close the car doors and let the car go to sleep for about 15 minutes. Put a multimeter across the battery terminals of both battery`s and take readings, 12.7/8 means the battery`s are good fully charged and have held that charge overnight.
My Car is a C-Class Coupe cgi December 2011, it has it`s original batteries which were recently tested at 12.8 volts, they are showing no sign of failure, I have never used stop/start.
There are I believe 3 systems linked to the battery sensor attached to the starter battery, auto stop/start, brake hold and energy regeneration. The sensor is there to monitor the state of charge of the battery (SOC), this is to ensure (1) there is enough charge in the battery to be able to restart the car after it has been stopped by the auto system (2) there is enough room in the battery for any high voltage regenerating, this means the starter battery`s SOC can be as low as 75% at any time, (3) there is enough energy in the battery to enable brake hold.
To test the battery the car has to rest overnight to allow any surface charge on the plates to dissipate otherwise a false high reading is observed, a fully charged battery should read 12.7/8 volts, after resting overnight release the bonnet and boot close the car doors and let the car go to sleep for about 15 minutes. Put a multimeter across the battery terminals of both battery`s and take readings, 12.7/8 means the battery`s are good fully charged and have held that charge overnight.
My Car is a C-Class Coupe cgi December 2011, it has it`s original batteries which were recently tested at 12.8 volts, they are showing no sign of failure, I have never used stop/start.
Thanks for additional info. I reckon my stop/start - when everything up to temp etc - would probably be used about half a dozen times over 10 miles a day. Not too fussed about that, but I am missing the Brake Hold.
Had battery tested this morning (as with yesterday, a good few secs of cranking to start, and ABS/ESP warning). They did an on-load check (big big wattage resistor across the posts), and reckoned it was looking a little weak.
Battery is at least 4yrs old for sure, and may well be the original (7-8yrs).
New battery due Thursday.... hoping it will cure things....
Had battery tested this morning (as with yesterday, a good few secs of cranking to start, and ABS/ESP warning). They did an on-load check (big big wattage resistor across the posts), and reckoned it was looking a little weak.
Battery is at least 4yrs old for sure, and may well be the original (7-8yrs).
New battery due Thursday.... hoping it will cure things....
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- 2022 Hyundai IONIQ 5 RWD / 2016 Suzuki Vitara AWD
My bet? 90% chance that a new main battery will fix the Stop/Start, HOLD, slow cranking, and ESP/ABS issues.
If it`s original battery you will see a stamp on top of one of the starter battery lead posts, mine reads 0911, Sept 2011.
A little weak does not mean the battery`s bad.
There is a post on the SLK UK forum by member Col, he had a failing sensor, stop/start intermittent and no cylinder deactivation on his SLK 55, a used sensor off Ebay fixed the issue, the thing was, with the sensor disconnected cylinder deactivation worked OK but Brake hold and stop/start as expected did not. With the faulty sensor connected cylinder deactivation didn`t work.
ECO Start/Stop SLK55 switching off!
A little weak does not mean the battery`s bad.
There is a post on the SLK UK forum by member Col, he had a failing sensor, stop/start intermittent and no cylinder deactivation on his SLK 55, a used sensor off Ebay fixed the issue, the thing was, with the sensor disconnected cylinder deactivation worked OK but Brake hold and stop/start as expected did not. With the faulty sensor connected cylinder deactivation didn`t work.
ECO Start/Stop SLK55 switching off!
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wongl
MB Enthusiast
Agreed. Most of my factory fitted MB batteries have lasted over 10 to 12 years by simply putting them on trickle charge twice a year (once before the onset of winter and once in spring). They tend to let go when left in storage without charging (e.g. my W210 estate) so I always try to replace the batteries from MB if/when they are competitive. If not competitive, a Varta battery will be a good alternative, but there is a school of thought (even a myth perhaps?) that the Varta batteries are not manufactured to the same standard as the MB branded Varta batteries. Certainly, I have never seen a 10 to 12-year-old Varta (non-MB) battery in action myself. Would be interested to hear from other forum members if they have seen a 10+ year Varta battery in action?
That said, I will be shortly replacing the batteries in two of my W169 and I will likely be using Varta batteries as I do not intend to be keeping them for more than 3 to 4 years as they are already getting a bit long in the tooth.
wongl
MB Enthusiast
Did you get the Aux Battery tested too? In my case, the Aux Battery was preventing start/stop but it had sufficient capacity to support Brake Hold. After replacing the Aux Battery it immediately resotre the ECO Start/Stop.
I fitted a new main battery 10 days ago, and have had working Brake Hold and Stop/Start ever since.
A Varta battery bought from Tayna. Tayna's 'part/model search' isn't all that great - instead I googled the MB part number, and that took me to Varta's own site. Spec/dimensions all the same. And a lot lot cheaper than the MB part.
If I were Varta, I'd put more effort into quality of my own brand than into MB-rebranded.... And, tbh, why manufacture to two specs? Just increases factory overheads.
(Jeez though, that thing is heavy to wiggle out of the crack of the bonnet hinge...!)
A Varta battery bought from Tayna. Tayna's 'part/model search' isn't all that great - instead I googled the MB part number, and that took me to Varta's own site. Spec/dimensions all the same. And a lot lot cheaper than the MB part.
If I were Varta, I'd put more effort into quality of my own brand than into MB-rebranded.... And, tbh, why manufacture to two specs? Just increases factory overheads.
(Jeez though, that thing is heavy to wiggle out of the crack of the bonnet hinge...!)
Now, if I can just get the passenger rear window to close when shutting the door.... Managed to re-sync the driver's side this morning, but don't remember what precise operations/sequence was the one that worked! 
wongl
MB Enthusiast
A couple of reasons really:
1. MB buys a million (?) batteries each year for every car rolling off their production lines. Low distribution costs (no middle man, small deliveries to many different locations, etc).
2. Costs - when selling something through retail, factory costs can be 20 times at the shop. This means that a 1p cost at the factory will increase to 20p at the shop. So Varta has to keep their own branded items sold through shops a lot cheaper.
