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Old 23rd May 2020, 11:30   #1
skellum
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Default ZT 120 fan on early.

Started our ZT 120 today just to swap cars around on the drive (TF needs attention) and noticed the main radiator fan came on very quickly. Car was still cold, temperature needle barely moved from stop. Fan stopped as soon as engine turned off.
Some reading suggests this might be a problem with the coolant temperature sensor- if it isn't delivering a signal the car 'plays safe' and turns on the fan.
This will sound really sad, but where is the sensor located??
Or, anything else might need checked?
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Old 23rd May 2020, 12:21   #2
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Started our ZT 120 today just to swap cars around on the drive (TF needs attention) and noticed the main radiator fan came on very quickly. Car was still cold, temperature needle barely moved from stop. Fan stopped as soon as engine turned off.
Some reading suggests this might be a problem with the coolant temperature sensor- if it isn't delivering a signal the car 'plays safe' and turns on the fan.
This will sound really sad, but where is the sensor located??
Or, anything else might need checked?
If the temperature sensor is disconnected, the MEMS3 sees a default temperature of iirc minus 140 degrees C, and the fan runs continuously.

The sensor is screwed into the top hose coolant outlet elbow on the right hand side of the cylinder head.

Brian
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Old 23rd May 2020, 12:57   #3
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Thanks Brian.
Will have a look when lashing rain stops- we have a weather warning on for today!
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Old 23rd May 2020, 13:13   #4
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Started our ZT 120 today ... and noticed the main radiator fan came on very quickly.
Colin; I was going to suggest that you checked that air conditioning wasn't selected but then I noticed that you live in Stornoway.

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Old 23rd May 2020, 14:41   #5
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Aha- if aircon is selected the fan will come on? Didn't realise, so will have to go check. Our boy was driving the car yesterday, so he might have turned it on. That would be the easiest fix I've ever come across.

As for living in Stornoway, we have just had a spell of fabulous weather. Glorious sun, weeks of driving the TF top down every single day. I got so used to it I even forgot to close her one night and she sat with the roof down overnight. Ordinarily a disaster, got off with it. We even had a couple of wildfires after the moor got too dry.
Last 48 hours though it's business as usual. Driving rain and high winds. Made it home yesterday afternoon before the coastguard closed the causeway. With high tide and high wind together the sea sometimes breaks over the road, and brings the beach with it. Makes for interesting driving conditions.
Cheers,
Colin
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Old 23rd May 2020, 15:41   #6
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I have a Rover 45 with Aircon & that if left on, switches the fan on as soon as the ignition switch is turned.
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Old 23rd May 2020, 16:51   #7
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Thanks, RoverP480.
Hoping this is all that's wrong, but our lad is off to the girlfriends with the car.
I'll be lucky to see it again this weekend
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Old 23rd May 2020, 17:39   #8
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As for living in Stornoway, we have just had a spell of fabulous weather. Glorious sun, weeks of driving the TF top down every single day.
There's no C-19 lockdown then?


TC
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Old 23rd May 2020, 17:52   #9
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There's no C-19 lockdown then?


TC
Going to the shops to buy a pint of milk per day seems perfectly acceptable to me TC

Brian
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Old 24th May 2020, 06:30   #10
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Good Morning T Cut. Yes indeed we have lockdown. I work in NHS at a fairly senior level. Sometimes I can work from home, but have a clinical role which means more days than not I'm in the clinic. While the ZT was being recommissioned the only car at my disposal was the TF.
When I drive her the top is down, no matter what the weather. Only thing that stops me is when the roof is actually frozen, quite uncommon here. The island climate is moderated by the sea temperature, so extremes either way are rare. Perfect place to have a convertible.
Cheers, Colin
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