Fans not working

[Roy E6]

Help!! I've just refitted my rad, along with some new hoses. Filled and bled the system, but the fans are not coming on, Any ideas ? Thermostat is working fine, opening at 74 degrees. Otter switch is new and have checked fuses which are all ok. Dont really know what else to check. While i'm on the subject, what do i need to do to use the ecu to switch the fans on? (i have the omex 710 series ecu) Thanks in advance of any help.

Roy.

[Ant.]

Start by shorting the otter switch wires out with a piece of wire or a auto fuse and maybe get some one to listen for the relays clicking.

The 500's have two relays and two fuses for the fans. So make sure both fuses are ok, and maybe swap the relays.

As for driving the fans from an ECU, not sure about the Omex, but on the emerald you can simply feed the otter switch supply directly to the ECU and that will switch the relay(s) for you..

[Roy E6]

Ok, i have replaced the fuses, not that they were blown. New relays, not sure if they needed replacing,but what the hell. And still the fans do not work! try shorting them out at the otter switch and nothing. So that tells me that the fans are not getting any power, now i ain't got a clue. Anybody got any other ideas ??? Who would of thought changing the rad would of been this much grief!
Cheers in advance

Roy

[Peter66]

Hi Roy,

I am pretty sure it's an earth problem. Check the resistance between the earth fan and the chassis with a multimeter. High chance it's the earth at the bottom of the chassis in front of the rad.

Best,
Peter

[Colin RedGriff]

As Peter says I would check the earths, I had a very similar thing although it only affected one of the fans. Just run a temporary new earth from the connector on the fans to a clean earth point.

[Roy E6]

Ok chaps, will give it a go this afternoon and report back.
Cheers

Roy

ETA Yep dodgy earth, all working fine now. Thanks again

Edited by Roy E6 on Wednesday 10th June 17:26