Coolant temp sensor

Hi, I have a Freelander 1.8 T reg. Last year I had the head gasket replaced and it all been fine since. Only problem was the fan never comes on.
After looking into the loom area I found that all sorts had been done down there and I think someone had wired the fan to come on continuously and then someone else did the opposite.
I took it to an auto electrician and he has sorted it out but has asked me to try and get hold of a new temp sensor but with a single contact on it. He has mentioned the Mini part.
Has anyone come across this before, he says it will then work fine. He has showed me the fans running when he touches the wire to earth, but he has said to look for this single switch.
Does anyone a part number and where I can get one from?

One of the petrol heads should be able to confirm but I thought the correct ETC sensor for the fans should have 2 wires/contacts.

I don't know what he's is trying to do but if you rewire it with a single wire switch from a temperature gauge won't the fans stay on?

I think the frelander fans are controlled by the temperature sensor which switches them on and off at certain temperatures. Can't you get it wired as it origonally was ?

He says there is an issue with the ECU, so to bypass it and let the sensor control the off/on of the fan requries it to be single pole switch.

If you go that route you will need to select the sensor/switch you use carefully to get the cut-in temperature correct. :scratching_chin:
The normal set-up uses the sensor to feed the ECU and the ECU drives the fans via a relay.
I would fit a relay to switch the earth to the fan otherwise the new switch won't last long!
Maybe you will need your auto-electrician to take another look at how he has rewired it for you and fit a relay? :doh:

free willy said:

He says there is an issue with the ECU, so to bypass it and let the sensor control the off/on of the fan requries it to be single pole switch.

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But single wire temp sensors don't switch on and off they have variable resistance??

Years ago Kenlowe sold switches that went under a hose fitting to switch on thier electric fans. It was adjustable to set the temp. for different cars.

Try this link
www.scparts.co.uk/index/lang-2/lkz-...tm?PHPSESSID=88b81d38e342f196215177394b4846fb

What year is T-reg?

the sensor controls ignition timing and fan relay, what's the issue with the ECU

Not sure if these make sense as they are Rover part nos.

MEK100060 (should be dizzy cap engine)

MEK100170 later type

MG figures are fans on at 106 oC, off at 96 oC, should be same for LR


When the autospark touches the connector to earth, all he is doing is lowering the resistance to zero. Disconnecting the muti-pin on the sensor has the same result, whereby the fans come on.

Thanks for replies guys, but does anyone know of a single switch that'll fit in there?
T reg is 1997

Just to update. I found a switch that comes on at 87 and now i have cut it into the top hose and connected wires to it that the auto spark put there for me to use. fans will now come on when they should which is fine.
problem now is i have no temp gauge, its at zero all the time, he says it can't be done???
can anyone tell me how to wire the temp gauge back to its original position? that all that needs doing now to make it half decent again.

free willy said:

Just to update. I found a switch that comes on at 87 and now i have cut it into the top hose and connected wires to it that the auto spark put there for me to use. fans will now come on when they should which is fine.
problem now is i have no temp gauge, its at zero all the time, he says it can't be done???
can anyone tell me how to wire the temp gauge back to its original position? that all that needs doing now to make it half decent again.

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The K series petrol engine has 2 temperature sensors, one for the ECU which in turn controls the fan the other for the car temperature gauge so if this is used correctly you should have a working gauge.

Hi FreeWilly - glad you got your fans sorted.
Sorting the gauge may be a bit harder - see extract below from Rave system description -
Engine Coolant Temperature Gauge
The coolant temperature gauge indicates the temperature of the engine coolant. When the engine reaches normal
operating temperature, the gauge rests at the mid-point of the temperature scale.
If the engine coolant temperature becomes too high, the pointer will rise to the red segment of the scale to warn of an
engine cooling fault. At this position the engine coolant temperature is too high and continued operation could result
in engine damage; the vehicle should be stopped as soon as possible.
The engine coolant temperature gauge is driven by a CAN message from the ECM. The ECM derives the engine
coolant temperature from an engine coolant temperature (ECT) sensor. Refer to the applicable Engine Management
System section for ECT location and description.
+ENGINE MANAGEMENT SYSTEM - MEMS, DESCRIPTION AND OPERATION, Description.
+ENGINE MANAGEMENT SYSTEM - SIEMENS (ALL EXCEPT NAS), DESCRIPTION AND OPERATION,
Description.
+ENGINE MANAGEMENT SYSTEM - EDC, DESCRIPTION AND OPERATION, Description.
+ENGINE MANAGEMENT SYSTEM – SIEMENS (NAS), DESCRIPTION AND OPERATION, Description.
The temperature gauge is fitted with a return magnet causing the gauge to return to zero when the ignition is switched
off. The coolant temperature gauge is only operative when the ignition switch is in position II or when diagnostics are
selected.
When the engine is hot, the gauge will display normal temperature until the engine has been running for more than
15 seconds. This prevents the gauge moving to the red sector of the gauge if the ignition is turned off and then on
after a journey. If the engine is not started, the coolant pump will not circulate coolant and local hot spots occur in the
engine and give an incorrect temperature reading. The 15 second delay allows for the engine to be started and coolant
circulated, allowing the gauge to display the true average temperature.
Coolant Temperature Gauge Needle
Position
Engine Coolant Temperature °C
Cold 40 (104)
Normal 75 - 115(167 - 239)
Hot (Red zone) 120 (248)
The gauge is driven by the CAN bus (digital) signal from the ECU using the signals from the sensor you removed?
Best of luck mate

thanks for the good news, i will most probably leave it as is then.
how much work is it to replace the ECU which is supposed to be faulty and at what cost?

free willy said:

Thanks for replies guys, but does anyone know of a single switch that'll fit in there?
T reg is 1997

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I don't think so.... P. is 1997.... T is 1999. I have been looking for a 300 Tdi and want it to be one of the last they built 1998 R or S. You can check it out on the DVLA web which allows you to check if a vehicle is taxed or nor not. Try typing in DVLA REPORT UNTAXED VEHICLE... Just have to type in the reg number and make of the vehicle. It then tells you the year of manufacture and the date of first registration and also date the tax expires and date the M.O.T expires. You can use the registration numbers from photos in a Land Rover magazine. Try it.

LifetimeLandy said:

I don't think so.... P. is 1997.... T is 1999. I have been looking for a 300 Tdi and want it to be one of the last they built 1998 R or S. You can check it out on the DVLA web which allows you to check if a vehicle is taxed or nor not. Try typing in DVLA REPORT UNTAXED VEHICLE... Just have to type in the reg number and make of the vehicle. It then tells you the year of manufacture and the date of first registration and also date the tax expires and date the M.O.T expires. You can use the registration numbers from photos in a Land Rover magazine. Try it.

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Golly, Don't you think he's sorted it out in the last 4 years?

Thread started : 1st-November-2010

lenny1234 said:

Golly, Don't you think he's sorted it out in the last 4 years?

Thread started : 1st-November-2010

Click to expand...

Doh... had not noticed date of thread. lol. no excuse for being caught like that again. Cheers Lenny.