Smart Charge Cars

[Rob Gaskin]

I was reading the other day about Smart Charging cars, not Smart Chargers but apparently modern cars have the charging rate controlled by the ECU and not the Alternator.

I admit to not realising that. The problem was as usual that the article didn't give enough detail so it was confusing.

Anyway besides not fully understanding the reason for this it also stated that you should never 'Jump' start a modern car because the ECU can be damaged. I wasn't sure whether that meant the Charging car or Accepting car should not be the Smart type.

I have 'Jumped' my lads Pug 306 from my 370Z so is this a No No? Got away with it though.

[nissanabuser]

Never heard of thi, diode pack in altenator controls flow and amount of current I thought, have to look into this now

[johnymd]

What if the whole car is Smart? not just the charging. I've jump started my Smart.

Anywaym, back to the point. It makes sence to use the ecu because you can controller ther perameters better and taylor the charging for all conditions. Be very interested to find out as I always dismiss the coments about it damageing the car.

[Rob Gaskin]

Originally Posted by johnymd

Be very interested to find out as I always dismiss the comments about it damaging the car.

And me

Seems modern charging systems take into consideration ambient temp and load on the engine to increase charging efficiency, reduce fuel consumption and increase engine power during acceleration.

[moggy240]

some modern cars can only be jump started from certain points in the engine bay otherwise you can damage the ECU

[johnymd]

Interesting moggy. I wondered why they put the battery points in the engine bay.

[tel240z]

If you have to jump start a vehicle the vehicle with the flat battery should have the head lamps switched on before the leads are connected, this is to reduce the surge and spike of current to the cars electrical components ie ECU,s

smart charging systems are where the alternator has the abillity to charge at extremely high currents first thing in the morning after starting, the system also moniters engine temperature so that a cold battery can take the high charge rate without overheating a common mistake is to fit a standard lead acid battery to cars equipped with smart charge that cant put up with 80 amps thrown at it every day, this is why silver calcium batterys are used for smart charge systems

And again if you have to use your car for jump starting a vehicle connect the leads before starting and once connected leave to run to charge the flat vehicles battery for 10 mins then switch off before starting the other vehicle

[Rob Gaskin]

Originally Posted by tel240z

If you have to jump start a vehicle the vehicle with the flat battery should have the head lamps switched on before the leads are connected, this is to reduce the surge and spike of current to the cars electrical components ie ECU,s

smart charging systems are where the alternator has the abillity to charge at extremely high currents first thing in the morning after starting, the system also moniters engine temperature so that a cold battery can take the high charge rate without overheating a common mistake is to fit a standard lead acid battery to cars equipped with smart charge that cant put up with 80 amps thrown at it every day, this is why silver calcium batterys are used for smart charge systems

And again if you have to use your car for jump starting a vehicle connect the leads before starting and once connected leave to run to charge the flat vehicles battery for 10 mins then switch off before starting the other vehicle

Excellent info.

[tel240z]

Some info for all you BMW owners, dont get one unless your rich

Had a 3 year old 1 series in the workshop today that kept showing low battery charge mesage on the dashboard (ie the battery is getting flat not meaning its not charging)
Now this is where it gets interesting, normally just order a new battery either lead acid silver calcium or gell (AGM) power up the vehicle and fit, job done, hang on a minute didn't i read that some of these stop start equipped cars need the battery programming to the car

long story short aftermarket battery £180 genuine BMW £260 Bmw dealer only programming £60

Reason being the cars ecu constantly moniters the battery condition and even remembers how much charge it can take at any given temperature and what condition the battery is in, so a battery that has limited capacity will only be given charge stored by the ecu, so fitting a nice new absorbsion glass matt (AGM) battery without telling the car can couse all sorts of expensive problems (watch out kwik fit euro and the tyre exhaust battery centres)

So i sent the customer to the local BMW dealer he wasn't amused at £320

Just out of warranty

[Rob Gaskin]

It's getting ridiculous, running modern cars will not be affordable to the person who usually buys a 5 year old car (like my kids).

Bought a battery yesterday actually for Lee's 4 Motion 2002 Golf. Bosch 60Ah (S4 075) £57. I thought that was ok, in fact cheaper than I expected.