Ford C-MAX 2.0 TDCI Ghia - C-Max Flat Battery

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Mon 27 Feb 2012 22:22
Ford C-MAX 2.0 TDCI Ghia - C-Max Flat Battery - LeeRossOnWye

I have had a persistent problem with the battery on my C-Max going flat after about 1 week when not usyed. The car has been to the ford dealer a few times but they have not been able to find anything wrong. We have had a new battery fitted but this made no difference. I have checked the drain on the battery and found it to not go below about 300mA, removing fuses one at a time it looks like removing the fuse for the electronic parking brake reduces the current to a reasonable level.

Does the parking brake always cause this much current or should it turn off after the brake has been applied?

Could the issue be a calibration problem with the brake?

Is there a relay which should disconect power to the circuit after it is applied?

Are there any other areas I should be looking at which could cause the battery to be drained?

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Tue 28 Feb 2012 08:14
Ford C-MAX 2.0 TDCI Ghia - C-Max Flat Battery - elekie&a/c doctor

How low is a reasonable level?Drain needs to be less than 100mA after min 30 mins stand time.Unfortunately the fuse system on modern cars can be confusing as a particular circuit may be protected by more than one fuse.So removing the h/brake fuse may be also cutting the power to a different consumer .hth

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Tue 28 Feb 2012 18:35
Ford C-MAX 2.0 TDCI Ghia - C-Max Flat Battery - LeeRossOnWye

Left the car for about 1 hour as the current dropped until it stabalised at about 300mA after about 20 minutes.

How can I find out what other circuits may be effected by removing the EPB fuse?

The car is a 55 plate, is there no way for the Ford dealer to work out what is causing the drain?

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