Temperature sensor/sender

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cst_tsc
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Temperature sensor/sender

Post by cst_tsc » Thu Nov 26, 2020 7:22 pm

Planning on testing and/or changing my temperature sensor (2pin) on 2.5l ‘96 diesel, as fans run all the time, down on power and struggles to start. Any tips or tricks? Assume if I change it I will lose coolant.....but how much?

THANKS
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g8dhe
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Re: Temperature sensor/sender

Post by g8dhe » Thu Nov 26, 2020 10:36 pm

Your aware that if the Air Con is turned on that also turns on the fan.
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Bob
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Re: Temperature sensor/sender

Post by Bob » Fri Nov 27, 2020 12:16 am

Hi. :)

Don't forget you will need to bleed the system if the coolant level drops below the header tank. :wink:
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Re: Temperature sensor/sender

Post by rita » Fri Nov 27, 2020 11:54 am

cst_tsc wrote: Thu Nov 26, 2020 7:22 pm Planning on testing and/or changing my temperature sensor (2pin) on 2.5l ‘96 diesel, as fans run all the time, down on power and struggles to start. Any tips or tricks? Assume if I change it I will lose coolant.....but how much?

THANKS
Your best bet is to change it when the engine is cold and no pressure in the system, dont remove the caps. Remove the old one and put your finger in the hole ,remove finger and fit the new sensor. If you haven't tried you could remove wiring from old sensor and connect to new sensor before fitting.to make sure that this is your problem.
cst_tsc
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Re: Temperature sensor/sender

Post by cst_tsc » Fri Nov 27, 2020 11:46 pm

Thanks all. Was aware of AC driving the fans and this off.

Fans cone as soon as ignition is switched on and van won’t go into top gear/ lockout? when driving, and issues arose at the same time. From reading, temp sensor could be the culprit, and like the idea of plugging in the new one before I remove the old.

Anything else that could cause my symptoms, that I should check?

Thanks again
rev
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Re: Temperature sensor/sender

Post by rev » Sat Nov 28, 2020 3:29 pm

Update us Sir if it thus solve also the problem of not shifting gears...I also has the same problems.. Thanks
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Re: Temperature sensor/sender

Post by Bob » Sat Nov 28, 2020 4:58 pm

Hi

This thread might help:

viewtopic.php?f=3&t=77451&hilit=Gearbox

Otherwise the 'search' box, top left, is useful. :wink:
rev
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Re: Temperature sensor/sender

Post by rev » Mon Nov 30, 2020 4:54 am

Thank you Sir Bob... :) :)
cst_tsc
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Re: Temperature sensor/sender

Post by cst_tsc » Tue Dec 01, 2020 8:33 pm

rita wrote: Fri Nov 27, 2020 11:54 am
cst_tsc wrote: Thu Nov 26, 2020 7:22 pm Planning on testing and/or changing my temperature sensor (2pin) on 2.5l ‘96 diesel, as fans run all the time, down on power and struggles to start. Any tips or tricks? Assume if I change it I will lose coolant.....but how much?

THANKS
Your best bet is to change it when the engine is cold and no pressure in the system, dont remove the caps. Remove the old one and put your finger in the hole ,remove finger and fit the new sensor. If you haven't tried you could remove wiring from old sensor and connect to new sensor before fitting.to make sure that this is your problem.
Just tried connecting the wiring to the new sensor without removing the old, and no change. The rad fan and scavenger fan both come on immediately when the ignition is turned on - so not the sensor? What else could it be? Both fans run continuously, which is not normal. Have tried the search bar, and no help there.......any other ideas greatly appreciated.
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Re: Temperature sensor/sender

Post by Bob » Tue Dec 01, 2020 8:42 pm

I'm guessing the new sensor was earthed? :wink:
cst_tsc
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Re: Temperature sensor/sender

Post by cst_tsc » Tue Dec 01, 2020 9:14 pm

It was plugged into existing wiring loom - does it need an additional earth?
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Re: Temperature sensor/sender

Post by g8dhe » Tue Dec 01, 2020 9:17 pm

No the engine sensor is two wire and is insulated from earth.
The sensor for the display on the dashboard is a single wire, and an earthed body but that doesn't control the fans.
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Re: Temperature sensor/sender

Post by Bob » Tue Dec 01, 2020 9:37 pm

g8dhe wrote: Tue Dec 01, 2020 9:17 pm No the engine sensor is two wire and is insulated from earth.
The sensor for the display on the dashboard is a single wire, and an earthed body but that doesn't control the fans.


Thanks. :wink:
cst_tsc
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Re: Temperature sensor/sender

Post by cst_tsc » Tue Dec 01, 2020 11:28 pm

So connecting an earth is not necessary? And connecting the new sensor, even With the old one remaining in the engine, but disconnected means it is not a faulty sensor? So if not the sensor, what is causing the fans to run all the time?
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Re: Temperature sensor/sender

Post by g8dhe » Wed Dec 02, 2020 9:47 am

The engine sensor uses two wires only. There is no earth connection required.
As to your problem it really needs more detailed investigation to find out what is happening just using a multi-meter to check the voltages around the sensor would be a good start but, given that your also having gearbox problems there might be a common problem or not.
Geoff
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