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Mercedes 2002 Diesel Auto E class "Elegance" - Battery - misterbee

Where i live, the car is a bit exposed to the weather and when its freezing , it does start but i reckon if it was left for a longer term it may struggle.

I remeber driving the old Dodge postal vans and having to be towed /jumped started on freezing mornings.. My question/curiosity is , does the cold weather actually drain the diesel battery , for example , lets assume you left the car for a week or 2 in cold conditions but returned when it was above freezing perhaps , as an example, 1o degrees or so..Would the previous cold nights affect a physical drain on the diesel battery , or, would it start as you left it. , Brain.

Mercedes 2002 Diesel Auto E class "Elegance" - Battery - RT

The fully charged voltage of a battery drops as the temperature drops - and the engine is harder to crank as the oil is thicker - so a failing battery can be fine all summer and then let you down in the first cold spell.

My Vauxhalls had batteries that outlasted the cars, 14 years in one case, but my Subaru's Panasonic battery started failing during its 2nd winter.

Mercedes 2002 Diesel Auto E class "Elegance" - Battery - elekie&a/c doctor

The battery on these is inside the car,either under the back seat,or in the boot (depending on model),so there is some protection from extreme cold.If the correct battery is up to spec,then there should be no problems after leaving the car for any reasonable period.Make sure the terminals are kept clean and corrosion free and also that the top of the battery is kept clean and dry.It is possible to get voltage leakage across the top of the battery between the terminals.

Mercedes 2002 Diesel Auto E class "Elegance" - Battery - misterbee

Thankyou, yeah , youre spot on , its under the back seats...i think its about 8 years old,

Mercedes 2002 Diesel Auto E class "Elegance" - Battery - misterbee


Mercedes 2002 Diesel Auto E class "Elegance" - Battery - Cyd

NO, the cold does not, of itself, remove any of the energy stored in the battery. In physics, temperature is a measure of energy, so as the temperature drops, the chemical energy available to be converted to energy is reduced. That and the fact a very cold engine is much harder to crank and start provides a triple whammy which a poor battery simply might not be able to overcome.

Also note that as temperature drops a battery’s ability to be charged is reduced. The reduction is progressive below 5C and below -5C most batteries will not accept charge. Another reason batteries die suddenly in the winter even if they were fine in the summer)

I would recommend that everyone should test their battery and charging system once a year, before it starts getting cold.

Being in the boot, yours has some protection from the cold and receives some warmth from the cabin during driving. The main reason it’s there though is packaging space and shifting weight to the rear.

I show you how to test your battery and charging system here:


All you need is a multimeter and some basic knowledge.

Mercedes 2002 Diesel Auto E class "Elegance" - Battery - misterbee

Thankyou very much , that has answered the question, much appreciated, Brian.

Mercedes 2002 Diesel Auto E class "Elegance" - Battery - elekie&a/c doctor

At 8 years old,it is probably due for renewal.Find a garage that can carry out a conductance test.This will analyse the crank amps availabilty of the battery.This is the standard that all battery/car makers follow for testing.


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