Fan constantly on

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Kernowel
Junior Bongonaut
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Joined: Fri Oct 06, 2023 5:20 pm
Location: Mullion Cornwall

Fan constantly on

Post by Kernowel » Sat Aug 02, 2025 1:05 pm

Hi I have an AFT diesel and 'The Fan' has recently started coming on as soon as I turn the ignition on - and it is constantly on. I note that Doone memberlist.php?mode=viewprofile&u=57 said earlier " If the auxiliary fan (scavenger fan) is running all the time, then the temperature sensor by the handbrake is disconnected.
Excuse my stupidity but which one is the aux fan and which one is the primary fan and is it possible that one is missing??

Yes, I am that thick when it comes to Bongo auto engineering #-o

Cheers!
Hosk
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g8dhe
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Location: Worthing, West Sussex.

Re: Fan constantly on

Post by g8dhe » Sat Aug 02, 2025 1:16 pm

There are actually three sets of fans The pair behind the radiator for cooling the engine coolant and aircon radiator (these will be running if the Aircon is turned on all the time), then there is a scavenger fan down directly in front of the engine itself, this operates from the sensor under the handbrake and should only normally come on when static or slow moving and the engine compartment heats up. Then the fan in the aircon system under the bonnet simply for blowing air thru the front of the van (actually there is also a fourth for the rear aircon as well!).
Geoff
2001 Aero V6, AFT, full side conversion.
Kernowel
Junior Bongonaut
Posts: 17
Joined: Fri Oct 06, 2023 5:20 pm
Location: Mullion Cornwall

Re: Fan constantly on

Post by Kernowel » Sat Aug 02, 2025 1:26 pm

Thanks Geoff !
Kernowel
Junior Bongonaut
Posts: 17
Joined: Fri Oct 06, 2023 5:20 pm
Location: Mullion Cornwall

Re: Fan constantly on

Post by Kernowel » Sun Aug 03, 2025 11:55 am

Can anyone tell me which connector, if any, is the one for the scavenger fan? Cheers!
20250803_113549.jpg
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g8dhe
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Re: Fan constantly on

Post by g8dhe » Sun Aug 03, 2025 12:06 pm

Its the one on the right, black circular, it projects down into the engine housing to monitor the engine housing temperature, this then feeds the ECU which turns the fan ON/Off as required.
Geoff
2001 Aero V6, AFT, full side conversion.
Kernowel
Junior Bongonaut
Posts: 17
Joined: Fri Oct 06, 2023 5:20 pm
Location: Mullion Cornwall

Re: Fan constantly on

Post by Kernowel » Sun Aug 03, 2025 3:08 pm

Cheers!
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