Offroad-Express

I am fitting a turbo timer on my patrol. It is a simple 12 volt analog type with four wires, red, yellow, blue and black.
Does anyone know which wire goes where? I guess the red is battery and probably yellow is acc with black being earth. whatnis blue for? And are my assumptions correct?
See photo for timer type and wire colours.




I have searched with Google and on ORE with little success, probably not using the correct words in the search to bring anything usable.

Thanks in advance

Cheers

Jase.

Red - Battery
Yellow - Ignition
Blue - Accessory
Black - earth

Thank you. I knew someone would know.