Hi,
New here but just thought I would post this message to say thanks for information I found on this forum. And getting my CLS to start!
- 2010 CLS diesel. Doesn't get used much. Less than 30k. Owned since 2012.
- Has been standing since April [9 months ago - when it received its last MoT]. I've been out of the country over past seven or eight years so unable to run it frequently. But it's been kept in an underground garage and has been MoT'd most years. It hasn't been maintained according to time schedule since 3 years old, but it has only done about 3,000 miles since then too.
- Dead battery since last summer.
First, I was fully expecting to buy a new battery [the original Mercedes battery was replaced with a Varta about three years ago. A CTEK device had been very successful at reviving the original and replacement AGM batteries over the past few years. But I realised I was on borrowed time with that strategy, and this time the engine would not crank. All electrics OK. Just no crank. So new battery bought and fitted - another Varta. Same symptoms. When the key turned to position 3 - no crank. I thought it might have been a 'bad' new battery. Connected it to the CTEK device to give it a full charge. Reconnected to car. Still no crank.
Thanks to this forum, this is what I did next:
- Ordered an iCarSoft MB II to read fault codes and a Fluke multimeter to test fuses. I started with the iCarSoft device. There were quite a few historic low voltage codes. Cleared those. But a 'current fault' was an open circuit in 5 of the 6 cylinders.
- Using information on this forum I learned that the glow plug relay often fails, to the extent that Beru had redesigned it. That seemed like a possible cause of the open circuits in 5 of the 6 cylinders. Also, the glow plug light on the dashboard went on and off before key position 3. Also glow plugs do last for 100k+ although I was aware they were circa 10 years old. I took a punt on the glow plug relay [more than likely to fail at some point over next few years anyway if it had been redesigned and numerous reports of failure!] and after removing the existing unit, checking its part number and ordering a new updated one for £80, I fitted the much lighter and smaller GSE114 unit.
- I reconnected the iCarSoft device. Hey presto!! Fault codes gone. Historic ones cleared. But problem solved? NO!! Still no crank!!
- Before having a crack at the fuses with the multimeter, my next step would have been to replace the starter motor relay [low cost item] after checking its fuse. I say would have been because I pulled out the 20amp fuse for the starter motor, saw that it had blown [cause or consequence?!?!] managed to temporarily borrow the 20amp fuse from the heated rear seats [I did not even know the rear seats were heated] and... hey presto: engine started! Yay!!!!
I'm going to be using the car much more now [as back in the UK] so obviously full service etc.,. I just posted the above to say thanks to the contributors to this forum, and also in case anyone else has a similar problem. I'm putting this down to faulty glow plug relay that blew starter motor fuse. Of course had I checked the starter motor relay fuse first.... ;-) ;-)
On another note, and bearing in mind the car has been in an underground garage for most of the past decade and only done 27k, the coating on the original AMG type alloy wheels is completely peeling off.
I understand this does happen. Any advice on a) fixing this, b) worth approaching Mercedes about this?
I have a 2005 Alfa GTV in the garage owned since new and on just over 50k. [which incidentally started first time after 18 months!] Its paintwork - being red - is poor and needs refreshing. But its alloys look brand new. Puts the CLS alloys to shame.
Many thanks again for collective help with solving my cranking issue over previous posts - much appreciated.
New here but just thought I would post this message to say thanks for information I found on this forum. And getting my CLS to start!
- 2010 CLS diesel. Doesn't get used much. Less than 30k. Owned since 2012.
- Has been standing since April [9 months ago - when it received its last MoT]. I've been out of the country over past seven or eight years so unable to run it frequently. But it's been kept in an underground garage and has been MoT'd most years. It hasn't been maintained according to time schedule since 3 years old, but it has only done about 3,000 miles since then too.
- Dead battery since last summer.
First, I was fully expecting to buy a new battery [the original Mercedes battery was replaced with a Varta about three years ago. A CTEK device had been very successful at reviving the original and replacement AGM batteries over the past few years. But I realised I was on borrowed time with that strategy, and this time the engine would not crank. All electrics OK. Just no crank. So new battery bought and fitted - another Varta. Same symptoms. When the key turned to position 3 - no crank. I thought it might have been a 'bad' new battery. Connected it to the CTEK device to give it a full charge. Reconnected to car. Still no crank.
Thanks to this forum, this is what I did next:
- Ordered an iCarSoft MB II to read fault codes and a Fluke multimeter to test fuses. I started with the iCarSoft device. There were quite a few historic low voltage codes. Cleared those. But a 'current fault' was an open circuit in 5 of the 6 cylinders.
- Using information on this forum I learned that the glow plug relay often fails, to the extent that Beru had redesigned it. That seemed like a possible cause of the open circuits in 5 of the 6 cylinders. Also, the glow plug light on the dashboard went on and off before key position 3. Also glow plugs do last for 100k+ although I was aware they were circa 10 years old. I took a punt on the glow plug relay [more than likely to fail at some point over next few years anyway if it had been redesigned and numerous reports of failure!] and after removing the existing unit, checking its part number and ordering a new updated one for £80, I fitted the much lighter and smaller GSE114 unit.
- I reconnected the iCarSoft device. Hey presto!! Fault codes gone. Historic ones cleared. But problem solved? NO!! Still no crank!!
- Before having a crack at the fuses with the multimeter, my next step would have been to replace the starter motor relay [low cost item] after checking its fuse. I say would have been because I pulled out the 20amp fuse for the starter motor, saw that it had blown [cause or consequence?!?!] managed to temporarily borrow the 20amp fuse from the heated rear seats [I did not even know the rear seats were heated] and... hey presto: engine started! Yay!!!!
I'm going to be using the car much more now [as back in the UK] so obviously full service etc.,. I just posted the above to say thanks to the contributors to this forum, and also in case anyone else has a similar problem. I'm putting this down to faulty glow plug relay that blew starter motor fuse. Of course had I checked the starter motor relay fuse first.... ;-) ;-)
On another note, and bearing in mind the car has been in an underground garage for most of the past decade and only done 27k, the coating on the original AMG type alloy wheels is completely peeling off.
I understand this does happen. Any advice on a) fixing this, b) worth approaching Mercedes about this?
I have a 2005 Alfa GTV in the garage owned since new and on just over 50k. [which incidentally started first time after 18 months!] Its paintwork - being red - is poor and needs refreshing. But its alloys look brand new. Puts the CLS alloys to shame.
Many thanks again for collective help with solving my cranking issue over previous posts - much appreciated.
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