Dear friends:

My battery charger has a 100 Ampere jump start feature. In the past, whenever I wanted to jump-start my gasoline cars using this capability of my battery charger, I just connected the + and -
cables from the battery charger to the discharged battery's electrodes WITHOUT disconnecting the battery cables from the battery's electrodes. However, Haynes manual for 240D says that I have to completely remove the battery cables from the battery's electrodes first and then connect the cables from a battery charger to the battery cables in order to jump-start a car using a battery charger. Otherwise, it will cause damage to a car's electrical system.

So which is the best and safest way to jump-start a car using a battery charger's jump-start capability?

For a diesel car with glow plugs (e.g. a 240D), will jump-starting a car using a battery charger (with 100 A jump-start capability) cause damage to the glow plugs' inner heating elements?

Thanks in advance for your help.

Eric

Eric,

I think Haynes is full of crap. I doubt if 100 amps would start a Diesel. If the charger is connected to the car cables and not eh battery, the only thing you would be protecting would be the battery.

I would be worried how high the voltage is that is being applied the car's electrical system by the charger. You might measure it. If the voltage is too high, you could possibly damage the GP and other electrical accessories in the car.

P E H