which is empty. I dont even know what sub fan is. I know its not for the electric fan in front of the radiator, as there is another relay for "RAD FAN" and the fan works, the only other fan I can think of is the heater fan, and the heater works. so what is it?
Its good to have but not hyper critical Your TT auxillary fan has two stages (low and hi) which kick in at preset high temps when the engine needs some help cooling down. Apparently these are pretty high up the temp range so a well maintained cooling system shouldn't need the fan assistance all that often. Without the sub fan relay, your auxillary fan won't kick in at the interim lower setting but (hopefully) will, once reaching the higher temp b/c you have the main fan replay. The sub fan relay is a sensible addition to get next time you're at the wreckers/supercheap etc. Probly not a super urgent thing but one to put on the todo list. The fact that you've noticed it's absence and posted about says you're prolly a preventative maitenance sort of guy (which is good!!!) ...:thumbsup:
thanks for that, I assume the fact that its a green relay socket means that the relay required is the same as the other green ones in the relay box, so I will take one of them into the shop with me, next time I go. I knew about the two different fan cycles, low and high sort of thing, but didn't realise that two relays were required, and that the sub fan is the low settings. thanks again.
Yep Yep, as I understand it. They aren't cheap so don't discount the wrecker idea? As long as the pins fit and all markings are identical, one from another nissan (other makes too?) would work too...opens up the opportunity... Tech article here if you're interested. Your relay might have been removed if the system faulty. A conzult can help you simulate the required temps to check fan operation
Both relays are needed for the fan to go into high speed mode. Your correct in saying you won't have a fan at the lower temp but by only having one relay for the high temp setting the fan will only run at low speed. Cheers Andrew
Interesting Wouldn't it just operate AT the higher speed and not at 'lower' speed given the missing relay is the 'sub' one?
No because the fan needs two 12volt connections before..>> it will go into high speed mode. Two 12v connections means it needs both relays. A little experiment next time you have the front panel off. Disconnect the fan connector, you'll see 3 pins, 1 is earth the other 2 are for power. (sorry can't remember what ones are what, you'll need a multimeter). Connect an earth to the earth pin & ten connect 12v to either of the other pins (low speed) then connect 12v to both pins at the same time (high speed) Cheers Andrew
Good logic ... haven't seen this info b4 but makes sense ... thanks for the clarification :thumbsup: Good to everyone to know with summer coming up...
