Submariner1
Senior Member
- Joined
- Sep 3, 2016
- Messages
- 4,728
- Reaction score
- 802
- Location
- Windsor Berkshire
- Your Mercedes
- CL500 2009 5.5
Just what I did not want for the weekend.
Pressed the KLG, Car does not even crank or click. All ignition lights come on, all other electrics seem to work, no error message.
The battery voltage is 12.3V . Could this be too low to let the engine crank? I know CLs like a decent voltage like over 12.5V
I tried with the normal key (KLG plug removed) Same problem. It runs through the first ignition setting like normal. Then all lights light up on the 2nd Position - but then in the 2nd Position a slight ‘smooth’ whine sound is emitted from dash console. This whine stays on until you turn the ignition to off position, and even then, it persists for a few seconds after turning the ignition off, before the whine stops and it goes silent.
Note There is no noise whatsoever, when you turn key to engage the starter, no slight click or anything. And no cranking at all.
Last week it failed to start once, oddly after I had charged it overnight. It started perfectly with a ‘vroom-start‘, I drove to local shops 2 miles, and it then failed to start to take me home. I thought maybe I had not pressed the KLG button hard enough. I Pressed KLG a second time and vroom an instant start.
** I am not sure what the tiny starter battery ( in the dash) does.
Q. If this has gone bad, could this be the issue? And how does one get at it , and test it?
any ideas folks?
I will call out Mobilo tomorrow, when hopefully they have Mercedes trained guys, as opposed to the weekend crew, who just tow it!
previous issues.
1. For about a year, oddly after Main Dealer changed the fuel filter, very occasionally the car seemed to crank for longer than usual; but it always started. And then it would revert to an instant vroom start For weeks and then repeat. At the last MD Service I asked them to check the Crank Position Sensor. They said it was fine and no previous CPS fault codes.
2. The KLG handle on the passenger side stopped opening the car door. However if you touch the driver side both door-lock buttons pop up and you can open the passenger side door physically. If you use the key ( i.e. press unlock button on the normal key) both door locks pop up. I was told its probably the 2 wires in the handle for the handle sensor, that have broken, but should not effect using the car. Just thought I would mention this. Note car has driven / worked fine for months.
3. Ever since changing the battery 3 years ago - it seems to go lowish voltage very quickly. Needs constant CTEK top up. MB checked it 2 x and said it was OK.
Note the new battery is 95 AH and the original one was 98 AH. I suspect these new batteries are crap, and the first one I put in lasted 1 week but lost so much charge the car would not crank, but made a noise like it was trying to. Mobilo diagnosed it a a totally faulty battery 11.2 V.
The replacement worked, but just didnt seem to hold a charge for 1 week, showing 12.4V not 12.6 to 12.7 like the 9 year old one.
They checked current drain 0.04 Amps to 0.02Amps , they said this was good.
Note:
** 1. mine is the single big battery version. But I understand there is some tiny “Starter“ Battery somewhere in the Dashboard.
2. The car has a tracker unit somewhere in it, not used, and definitely not in the location where Tracker UK said it was.
Q. Does anyone know, if this Tracker module failed would it allow the engine to crank but not fire up? Or display issues like mine, i.e. just does nothing.
Pressed the KLG, Car does not even crank or click. All ignition lights come on, all other electrics seem to work, no error message.
The battery voltage is 12.3V . Could this be too low to let the engine crank? I know CLs like a decent voltage like over 12.5V
I tried with the normal key (KLG plug removed) Same problem. It runs through the first ignition setting like normal. Then all lights light up on the 2nd Position - but then in the 2nd Position a slight ‘smooth’ whine sound is emitted from dash console. This whine stays on until you turn the ignition to off position, and even then, it persists for a few seconds after turning the ignition off, before the whine stops and it goes silent.
Note There is no noise whatsoever, when you turn key to engage the starter, no slight click or anything. And no cranking at all.
Last week it failed to start once, oddly after I had charged it overnight. It started perfectly with a ‘vroom-start‘, I drove to local shops 2 miles, and it then failed to start to take me home. I thought maybe I had not pressed the KLG button hard enough. I Pressed KLG a second time and vroom an instant start.
** I am not sure what the tiny starter battery ( in the dash) does.
Q. If this has gone bad, could this be the issue? And how does one get at it , and test it?
any ideas folks?
I will call out Mobilo tomorrow, when hopefully they have Mercedes trained guys, as opposed to the weekend crew, who just tow it!
previous issues.
1. For about a year, oddly after Main Dealer changed the fuel filter, very occasionally the car seemed to crank for longer than usual; but it always started. And then it would revert to an instant vroom start For weeks and then repeat. At the last MD Service I asked them to check the Crank Position Sensor. They said it was fine and no previous CPS fault codes.
2. The KLG handle on the passenger side stopped opening the car door. However if you touch the driver side both door-lock buttons pop up and you can open the passenger side door physically. If you use the key ( i.e. press unlock button on the normal key) both door locks pop up. I was told its probably the 2 wires in the handle for the handle sensor, that have broken, but should not effect using the car. Just thought I would mention this. Note car has driven / worked fine for months.
3. Ever since changing the battery 3 years ago - it seems to go lowish voltage very quickly. Needs constant CTEK top up. MB checked it 2 x and said it was OK.
Note the new battery is 95 AH and the original one was 98 AH. I suspect these new batteries are crap, and the first one I put in lasted 1 week but lost so much charge the car would not crank, but made a noise like it was trying to. Mobilo diagnosed it a a totally faulty battery 11.2 V.
The replacement worked, but just didnt seem to hold a charge for 1 week, showing 12.4V not 12.6 to 12.7 like the 9 year old one.
They checked current drain 0.04 Amps to 0.02Amps , they said this was good.
Note:
** 1. mine is the single big battery version. But I understand there is some tiny “Starter“ Battery somewhere in the Dashboard.
2. The car has a tracker unit somewhere in it, not used, and definitely not in the location where Tracker UK said it was.
Q. Does anyone know, if this Tracker module failed would it allow the engine to crank but not fire up? Or display issues like mine, i.e. just does nothing.
