Only one fan working. What to check

[KenInOntario]

Only one of my cooling fans is working. The one that kicks in at 94c is working ok, but the one at 92c never kicks in or starts.

What should I check first?

[KenInOntario]

Looks like both work but at the wrong temperature.

The 2nd one does come on, but only around 100 according to the POD display.

The beeping scares the st out of me lol!!

So, I guess it could be the POD sensor? IS it the same that sets off the fans?

[NCE 61]

There are two temperature sensors one under throttle body No2 which give the dash display temperature the other under throttle body No 5 which goes to the engine ECU and controls the cooling fans:-



Quiet often the display sensor reads higher than the ECU one which regarded as the more accurate one. To check the ECU value you will need the diagnostic software and lead.

[gacksen]

KenInOntario said:

Only one of my cooling fans is working. The one that kicks in at 94c is working ok, but the one at 92c never kicks in or starts.

What should I check first?

did you check that the fan connectors at the front are not corroded ?

[KenInOntario]

Not yet,

Both fans actually spin and work, just seems at too high a temperature. I have ordered new sensors, as I also noticed some drop in engine power sometimes when driving, which I read is also a symptom of a failing sensor.

I will change the sensors when I do the bonnet mod.

[dvs_dave]

As others have said, likely a bad Pod sensor or corrosion on the connector which is separate from the ECU sensor. The ECU sensor is what drives the fan control. You can check the fan control function by pulling the connector on the ECU sensor. As a failsafe, both fans should come on immediately. It'll be worth cleaning the connectors up on both sensors as corrosion on them will affect resistance which will lead to false readings.

Whilst you're there, you definitely need to check the electrical connectors on the fans. They're not waterproof connectors and they do corrode and stop working. Pulling the plugs, cleaning up the connectors inside and sealing them up with a bit of silicon is a good preventative maintenance step.

[natben]

Only one fan coming on would maybe point me to the fan connectors below the fan, they do get corroded. Take it apart and clean the connections.

[KenInOntario]

Stupid question, which is cylinder 2 and 5? From the front of the car is 6 or 1?

[gruffalo]

Front is one.

[KenInOntario]

Problem found. The dash sensor shows 10 - 13c difference to the ECU sensor.

I connected my PC to the ECU and the fans work correctly when I see the temp on the ECO Software readout