Ignition on 12v power in Engine bay

cidylong · Post by **cidylong** » 16 Jun 2020, 02:43

Hi. Sir/Madam

My car: 1995 850SE station wagon.

My ECU not get proper temperature value from my temp sensor, it always shows about 70°C event a brand new sensor installed, so ECU never send coolant fan "on" signal to coolant fan controller 1398845.

I'm trying to create a new fan controller logic system by using Davies Craig 0401 mechanical thermatic switch plus a 40A relay to control my coolant fan.

My problem is: I can't find +12V power supply in Engine bay under ignition on position to set up a fan controller to let the coolant only works on key on. As result, I have to use the batter +12V instead, this will make the coolant fan drain out battery some time.

Any one have any idea, please advise!

Post by **erikv11** » 16 Jun 2020, 11:37

You can use the yellow accessory connector under the dash. I haven't done it myself but there are a couple grommets in the firewall you can use to pass a wire from there to the engine bay.

cidylong · Post by **cidylong** » 17 Jun 2020, 01:59

The ignition +12v found in my fuse board, number 4.

Tested, works fine.

Post by **erikv11** » 17 Jun 2020, 07:53

There are definitely fuse box options, good thinking. Glad you got that part sorted.