Starting problem

[Zabarka]

Hello ,
I have a 2011 A class Mercedes.
I have never had any problems starting my car until now.
But the last few days, mainly first thing in the morning, but also other times, the car turns over but does not kick in,
After a few attempts, it does start.
Any suggestions, what is happening?
Thanks for your help.
Gus.

 

[mioba]

Whats the battery voltage before a start. Get a volt meter across it

 

[Zabarka]

Hello mioba ,
The battery is not very old, but I will take your advice and get it checked out.

 

[Misterdog]

Is yours petrol/diesel, does it have stop start ?
Is yours the 'old' A class like mine or the newer one.

 

[Zabarka]

My car was purchased from Mercedes on March 2012, the old version. Later in the year, it was changed to the newer version.
My car is a petrol model.
When you say stop start, do you mean the engine stops in a congestion then starts again ? If that is what you mean, it is what I have.

 

[Misterdog]

When you say stop start, do you mean the engine stops in a congestion then starts again ?

Indeed, this means that you have 2 batteries, one under the floor of the driver and one in the rear boot space (drivers side, side panel).

The designation for your vehicle is the same as mine W169, is yours an A160, A170, or A200 though ?

Do you know if either battery has been changed, though checking the voltage in the morning when cold, then after 30 seconds or so will tell whether the batteries are shot or the alternator is not charging properly.

A digital multimeter can be bought for £10 and there are plenty of tutorials on You Tube showing how simple this is to check. Or any garage can check.

The main battery on mine cost £ 120 with a 5 year warranty ( Varta) I assume yours is the same though we need to know the engine size.

Also your driving habits, do you only use it for short journeys, in which case the main battery which is used for starting may not get charged, especially if you leave the stop/start on ( always turn it off!!! until the problem is sorted ) .

 

[Zabarka]

Mine is a 160.
Well, this is all news to me.
Two batteries !!
How does one turn off the stop start?
I only do short journeys usually, unless we go on holiday, which obviously has not been possible during this time.
How long does one need to drive to charge the batteries?

 

[Misterdog]

How does one turn off the stop start?

The button labelled ECO which lights up green when the ignition is on (below heating controls) . Disable by pressing light goes out. you need to do this every time you turn on the ignition.

How long does one need to drive to charge the batteries?

Around 30 minutes. or longer do not have lights/radio/ aircon etc. on.

Get both battery voltages checked first, first thing when cold then with the engine running.

Both should measure 12.2 Volt minimum with engine off and 13/14 V with engine running ( alternator is providing charge).

 

[Zabarka]

Thanks Misterdog,
For the info.
The batteries were checked yesterday and appear to be charged.
I will take a trip down the M1 today and see if it makes a difference.
If not, I will book it into Mercedes and get them to figure it out.
Thanks for your advice.

 

[mioba]

Ideally you need to check the batteries first thing in the morning after a night of rest to see if they are holding charge before a start.

Although a trip down the M1 will give them some degree of charge, you need to figure out if they are holding charge.

But yes get it checked, could be you have a parasitic drain somewhere.

Good luck and do post back...assuming the problem is with the battery(ies) of course.