Eco Start Stop

[Craig245T]

Eco start stop system has stopped working. Green light shows on the button but constant amber light on the dash.
Varta battery was new about 18 months ago and I've charged it just in case, I'm convinced it's not that though. This car has no aux battery and that has been confirmed by Mercedes. Some don't have aux batteries apparently.

No fault codes, doors closed, bonnet closed, seat belt on, aircon etc is off. Engine temp normal.
Assuming it's not the battery, what can I check myself before getting professional help?

Mercedes want £200 to.connect it to their diagnostic machine, another wants £100.

Thanks in advance for any pointers
Craig

 

[geoffus]

What car do you have ?

 

[st13phil]

Assuming it's not the battery, what can I check myself before getting professional help?

Other than verifying that some previous owner hasn't pulled a fuse to disable it, precious little - or more precisely, nothing - I'm afraid.

There are so many sensors measuring so many parameters before Stop/Start will work, there's no substitute for Star diagnosis. That said, I had an E63 that the Stop/Start would sometimes refuse to work for weeks on end that visited the main dealer several times, had diagnostics run on it multiple times, had batteries (and other components) changed - all under warranty, I might add - that still had the Stop/Start go into an extended sulk every now and then.

 

[st13phil]

What car do you have ?

W176 A180d according to the OP's bio.

 

[Craig245T]

Yes, W176 1.5d

 

[Craig245T]

When I bought the car the system didn't work but if I charged the vehicle battery the system would work for a day then switch off as the battery voltage tailed off. Charging the 18 month old battery has no effect, this is why I'm convinced the battery is not the issue.

 

[Fastcar155]

Hi , well my car stop starts works when I drive the car at moderate speed.At motorway speeds the system does not work correctly / does not go green on the dashboard.

The battery's are as supplied with the car in 2015 , car to-date even starts on the button after weeks of no use.

When I was not in a good place I did some observations on stop start systems and I found generally they did not work. A Friend of mine has a Skoda Yeti who's system is poor. ( Cuts out when pulling out ) !

I am afraid to say I turn my stop start off automatically when I go out.

 

[geoffus]

The wifes B200 doesn't have a aux battery similar to yours, the stop/start works perfectly and its still on the original battery, 11 years old. But I always turn it off.
Mine is a E250 and the aux battery is shot so stop/start don't work at all.
If you want my advice then leave it alone, its a pain in the butt.

 

[MrGreedy]

I'd say forget about it. How much extra fuel are you going to use vs the £100-200 diagnostics fee? Unless the car spends it's life in stop start traffic, I'd bet the fuel saving isn't worth it.

Plus without stop start, it reduces wear on starter motor and belts, tensioners and pulleys, which can be expensive when they fail.

 

[Craig245T]

Thanks for all the replies, very much appreciated.
I agree the stop start causes extra wear and tear and the batteries aren't cheap. I can live without it but it just annoys me when something that should work doesn't. It's the way I'm wired up
Also makes me wonder what else is failing that's preventing the system working.

 

[OneForTheRoad]

Was type of battery was fitted ,. Wet acid or AGM , gel type . What type is meant to be fitted ?

 

[Gnasher141]

Mine too seems to have a mind of its own, most of the time it doesn’t work, then when it decides to work, I turn it off - not reliable enough!

 

[rf065]

When I bought the car the system didn't work but if I charged the vehicle battery the system would work for a day then switch off as the battery voltage tailed off. Charging the 18 month old battery has no effect, this is why I'm convinced the battery is not the issue.

It might still be the battery, have you measured the voltage? I've found the stop/start on these systems require 12.6v too work as designed, I've had a couple of cars with 12.2v and 12.4v where the stop/start never worked, put in a new battery and they started working again. Worth checking how many volts your battery has when fully charged.

 

[Craig245T]

Was type of battery was fitted ,. Wet acid or AGM , gel type . What type is meant to be fitted ?

AGM Varta I think. It was replaced by Mercedes Glasgow under the approved used warranty weeks after I bought the car.

 

[rf065]

AGM Varta I think. It was replaced by Mercedes Glasgow under the approved used warranty weeks after I bought the car.

Mercedes Glasgow, probably took a battery out of another car.

 

[Craig245T]

Mercedes Glasgow, probably took a battery out of another car.

I had actually thought about that when they replaced it. It's got 06.21 stamped into the top of the negative terminal which looks factory but you never know. I'll check the resting voltage tomorrow. I shouldn't assume the battery is OK I suppose.

 

[OneForTheRoad]

I had actually thought about that when they replaced it. It's got 06.21 stamped into the top of the negative terminal which looks factory but you never know. I'll check the resting voltage tomorrow. I shouldn't assume the battery is OK I suppose.

Give it 24 hours on a smart charger AGM mode . It should work the stop start tbh.

 

[Rubyred]

I second One For The Roads reply. My C200 is used very little and it takes ages for the S/S to function as the battery is not 100% charged. I now use a battery conditioner when car is stood unused and the S/S works first time when I use the car. But as others have said, I turn it off anyway.

 

[simon1963]

Mines the same, it’s never worked since I bought it 6 weeks ago. It’s been on star and no faults found. I had it on a tender for 4 days and still didn’t work. It’s going in to the dealer I bought it from for a new battery. I also am not bothered about it working but wanted it picked up and sorted under the warranty. Battery is five years old so hopefully that is the cause.

 

[OneForTheRoad]

Mines the same, it’s never worked since I bought it 6 weeks ago. It’s been on star and no faults found. I had it on a tender for 4 days and still didn’t work. It’s going in to the dealer I bought it from for a new battery. I also am not bothered about it working but wanted it picked up and sorted under the warranty. Battery is five years old so hopefully that is the cause.

Most likely. Mine died at around that age also. There are some however that last 10 to 12 years . We must just be unlucky. ?