fan control

[Redbox]

I'm looking for help, i would like to put a manual over ride on my fans so i can run them when doing low speed work,n i have found the 3 relays that control the fans but i need conecter pin numbers & locations for the ECU, the relays are earth switched & always powered.

So i was going to earth switch with releys so i can't turn on when key is out, i guess there will be 2 or 3 wires at the ecu.

any help would be great.

Thanks

[JK07]

Where are the 3 relays? Urs diesel or petrol and what year?

[Redbox]

there are 2 in relay box, K2 RUN RLY & K 11 RAD FAN LO RLY, the third is up next to the pas side head light (K175).

K11 gives low speed, K2 gives power to the coil of the third relay (K175).

K175 is the high power relay.

K2 & K11 are always powered up.

All are then earth switched by the ECM.

so i need ECU pin numbers so i can tap in, run to switch & earth switch throug a relay that is powered by the key, so it only works at on/run.

My jeep is a 2008 JKU Rubicon 3.8l v6 manual.

[MightyMouse]

Not that it will affect you but i'm not sure the relays are actually called K2,K11 and K175.

From looking at the wiring diagram and manual i think the "K" is a loom ID, but this could just be my reading of the diagram.

Also note the the fan in the factory wiring diagram is actually drawn as a two speed ( three wire ) motor... and in reality its not and doesn't have the internal emperature cutout as shown in the wiring diagram.

As you've probably figured out there is an extra Connector/resistor module attached to the fan shroud that creates the two speeds, on low the resistor is in circuit... on high bypassed. There IS a thermal "fuse" in this connector/resistor unit and its not at all reliable.

Also to note is the earlier connector/resistor units are different ( larger ) as they also contain a self resetting thermal circuit breaker, which seems to have been deleted in later models. The two different Resistor/connector modules are also NOT compatible as different pins are used..... why... who the hell knows ?

[Redbox]

thats good, i am down with that part of the system, it is the pin outs & wire colours in am chasing.

If i splice in to the pin at the ECM i can give earth with switch and i will have fan over ride.

i have founda few theads on this but they go no ware.

the outer option is to duplicate the whole system, this i see as point less

thanks

[MightyMouse]

High Speed Relay Control - TIPM Connector 3 ( Green ) Pin 2, Brown/Lt Blue wire, Active Low

[Redbox]

awsom, dont have the low speed pin aswell.

But this is a start.
Thanks