Fabia 1.2tdi start stop battery, coding?

[Lofty79]

So my start stop system isn't working, I get "engine must run" and then when the conditions are more suitable (warm engine etc) it just says "error stop start".

 

Everything else works fine and starting fine.

Just the stop start doesn't work. It did once in last week, but then doesn't again.

 

I've decided it's maybe time to replace the battery.

Going to go 70Ah AGM.

Will this battery need coding? Or will it function ok just fitted.

 

Any other suggestions as to why the stop start isn't working? Or am I heading in the right direction.

 

Cheers folks

[Ootohere]

Sorry no help,

   but seriously do you want it to work, mine is usually off because too cold, or the difference between the heat setting and outside temp is more than 16 degrees.

 

Today a year old car has sat below freezing for 3 days and refused to start 3 times, i put off the radio, went to DRLs, as there is no no lights, 

and luckily it fired.

Never had that for years. 

 

Stop / Start and stop start batteries are the spawn of the devil.

Now going to have to put jump leads in a 12 month old car with 17,000 miles so as never stuck in the hills.  Pith take.

[Lofty79]

I hate stop start.

However OCD makes me want to find the answer, so if there's a fault, I can fix it.......... Then disable it haha.

 

It's just the charging system is so complex that if the battery isn't playing ball, the ecu doesn't know how much charge the alternator needs supply it. 

This can cause burned out AGM battery or knackered altenator.

 

Not easy things to get to grips with these modern systems. Vcds coming back to me soon (leant it out) so will full system scan it.

Battery holds charge for long periods though and starts perfectly so not sure it'll be that bad.

 

Could also be remap interfering but it has stop started since Then.

 

My motto has always been "if it ain't broke, fix it until it is"

[delta925]

For stop / start the system has to know the nominal capacity of the battery so, in theory, it is never below a set capacity.

The problem is when in reality that capacity is lower than calculated. Add in suddenly colder weather, lights, heated rear window etc not to mention lights left on and the result is not enough actually in the battery for a startup.

 

When the battery is swapped the system has to be recoded with the new battery details.