2 probe coolant level sensor ?

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matt brighton
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2 probe coolant level sensor ?

Post by matt brighton »

Hi

How does this work ?

Having replaced my diesel with a petrol engine....

I now have a new expansion tank which has the 2 pin probes that sit in the water, and a redundant LED yellow glow plug light on the instrument panel.

Im thinking.... if I put the live feed with in line yellow LED to one of the probes and and connect the other to earth - does a drop in coolant level below the probes make the circuit - and light up the led ?

I will get a battery, wires and glass of water out later today to tinker - just wondering if anyone knows if this how the probes work to activate a buzzer or warning light ?, or do they go through a micro relay to activate a warning signal.

Thanks

matt

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slowcoach
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Re: 2 probe coolant level sensor ?

Post by slowcoach »

Pretty sure the coolant below the level breaks the circuit, The coolant is conductive to some degree.
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itchyfeet
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Re: 2 probe coolant level sensor ?

Post by itchyfeet »

there is a 'relay' no 43 in position 3 that detects the change in resistance and with some wizardry it brings the high temp light on the dash without raising the gauge, low resistance pulses I think.

I say 'relay' because is isn't a relay but looks like one
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itchyfeet
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Re: 2 probe coolant level sensor ?

Post by itchyfeet »

matt brighton wrote:
Having replaced my diesel with a petrol engine....

excellent choice :ok
1988 DG WBX LPG Tin Top
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matt brighton
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Re: 2 probe coolant level sensor ?

Post by matt brighton »

itchyfeet wrote:there is a 'relay' no 43 in position 3 that detects the change in resistance and with some wizardry it brings the high temp light on the dash without raising the gauge, low resistance pulses I think.

I say 'relay' because is isn't a relay but looks like one

Thanks for the reply - I see how it works now

- I Buggered my temp gauge when deleting the constant red led blinking by shaving off the centre pick up on the back of temp guage :oops: ...

So.... Im getting some aftermarket gauges for oil pressure/ battery voltage / and water temp -

Would like to use the yellow diesel glow plug led as a low coolant warning - so I guess I will have to identify a sensitive solenoid that will ground the live to that, when the probe breaks the circuit.

Thanks again

Matt

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