Hello,

after improving my audio sistem with an amplifier + sub, I realised that my Focus 1.8 TDCI (2007) has a big current draw at inicial cold start up (winter, low temperatures).

Checking voltages, I detected that my car has a big current draw the first two minutes....or three
minutes (aprox) when I start it up now in winter (ver low temperatures). Just for
curiosity, I would like to know what kind of System causes this current drain.
I think it could be something about engine heating.

Thank you. :D

could be the front heated windscreen? how are you checking the voltages? the one in the test mode is not 100% accurate

could be the front heated windscreen? how are you checking the voltages? the one in the test mode is not 100% accurate

Hello. What test mode?

I first noticed that with a little battery tester (the little one with three leds on the cigarette plug), that it is a voltimeter with three leds.

After that, I checked it with a digital multimeter, and realized that I have to rev the engine (alternator) to rise the voltage in this first minutes. After this mode ends.....voltage become ok, cutting at 14.2 V aprox. even at idle speed....(sorry for my written English).

Front heated windscreen? like the rear one? I think I don't have one like this.....Do you mean with cooper lines like the rear one?

Regards.

My guess would be the Glow Plugs that aid starting? Will operate for longer when cold.

Some cars have an electric PTC heater that will use a large current for a time http://www.fordownersclub.com/forums/topic/47782-retrofitting-ptc-heater-to-mk2/

My guess would be the Glow Plugs that aid starting? Will operate for longer when cold.

Some cars have an electric PTC heater that will use a large current for a time http://www.fordownersclub.com/forums/topic/47782-retrofitting-ptc-heater-to-mk2/

Thanks. I thought about the Glow Plugs too.....maybe they work some time after start, with less current than in "first Ignition mode"...

And thank you for the electric PTC heater information

My ST engine has a heater circuit built into the engine oil breather/recirc unit. Never knew it even had one till it went short circuit, blew the fuse and brought on the engine light.

It's there to help warm up the oil quicker I'm told, that'd be an obvious cause of extra current drain on start-up if other models use a similar system. Same with glow plugs, and also some electrical items can take a few minutes to initialise etc on start-up but this is more likely on the next generation of Focus with more complex electrical toys. I'd say the car puts some power into the HVAC/AC system as well when you first switch on.