6 replies to this topic

[Mini_Magic]

I'm finding recently that the eletric fan on my MPi will sometimes come on really soon, much before the engine temperature has reached optimum level. The fan will turn off shorty after the engine has been turned off, just as it did before after a long jorney. The engine still appears to warm up as normal and just as quickly gets up to temperature. The fan just comes on when the engine doesn't actually need the additional cooling.

[tomsbluemini]

sounds like fan cut off switch... mine does it too, i'm just waiting till I can be bothered to change it...

little brown thing just by the thermostat...

just under £15... about 20 seconds work

Tom

[elvisthepizzaman]

I was under the impression that the ecu did all the fan turning on and off based on what the brown temperature sensor was reading. Try giving the brown connector a good cleaning with some electrical contact cleaning solution (spray can) before replacing it and if the connectors are pitted use some fine sand paper. I find that it is the only connector that gets dirt in it due to its mounting position. Without a coolant temp, the ecu runs the fans all the time to protect the engine. its part of the safe mode or limp home setup coded into the ecu in the event a sensor goes out it can compensate for that particular one.

[Mini_Magic]

Ah it may be because I disconneted that sensor to get to the subframe tower bolt (long story). I'll try giving it a clean now.

EDIT: Well I unplugged it, gave it a good blow and plugged it back in.

Will see how it goes on the drive into work tomorrow.

Edited by Mini_Magic, 10 February 2008 - 08:06 PM.

[redhotmini]

I was under the impression that the ecu did all the fan turning on and off based on what the brown temperature sensor was reading. Try giving the brown connector a good cleaning with some electrical contact cleaning solution (spray can) before replacing it and if the connectors are pitted use some fine sand paper. I find that it is the only connector that gets dirt in it due to its mounting position. Without a coolant temp, the ecu runs the fans all the time to protect the engine. its part of the safe mode or limp home setup coded into the ecu in the event a sensor goes out it can compensate for that particular one.

the fan on mine has never worked - changed everything like the sensor, relay, fuse, etc. Got the fan rigged to a seperate switch, which is the only way it works. probably something buggered inside the ecu, i havent had it checked properly yet.

[Mini_Magic]

Well the fan didn't kick in this morning, but to be honest I wasn't really paying attention!

I'll see what happens on the drive home.

EDIT: The fan didn't turn on at all driving home, either it's working properly now or it's not working at all!

Edited by Mini_Magic, 11 February 2008 - 07:14 PM.

[nev_payne]

I solved this problem with a coolant flush through, new thermostat, and a new temp sender... fan since then only came on in still traffic after 10 minutes or so instead of say... 30 seconds.