Hoping to avoid other people wasting the time I have done on this. Basically my Freelander 1 (1999 1.8 petrol) arrived with a non-functioning coolant gauge - gauge needle not moving at all, but knew gauge itself was ok as it went to hot as soon as wire was grounded.
Someone had obviously been messing around with the gauge temp sensor before as the wire didn't have a plug on the end. The sensor that was in was the correct one YCB100420, though it was shot, reading way out from the RAVE manual specs - reading in the 10s of K ohms. For reference the correct readings on your meter are:
142.0 ohms Wide sector at cold
32.1 to 49.0 ohms 10 degrees below horizontal (engine normal operating temperature)
16.9 ohms Red sector at hot
Wiring diagram in RAVE shows it as a 1000 ohm variable resistor so a relatively high reading expected testing it from cold. You can see although there are two pins in the sensor they are connected together so you test between the sensor body and the pins.
Now the problems came when I tried ordering replacements. ERR2081 was showing as the correct replacement on ebay by various sellers so I ordered one. This is not the correct sensor although everyone seems to think it is!!!
It is a two pin sensor, does not earth through the body and the resistance value is way off - seems to be around 3000 ohms to 300 ohms.
Went to local independent parts place - was sold a WS1120 sensor. Again this sensor is not the correct part, it is a two pin sensor and resistance wildly off. Connector has a slight offset as well so won't plug in.
Ended up going to the local scrapyard and pulling a sensor off an old petrol rover 25. Just a warning - beware that a lot of people are selling these random sensors as compatibles - they aren't compatible with early freelanders! If you have two coolant sensors you must be very careful to check you are getting the right sensor as a lot of computer systems have decided that all K series coolant temp sensors are compatible which they are clearly not. If in doubt, go to the shop with your meter and test it there before you hand over the cash. Hope this saves someone ordering the wrong bits.
Someone had obviously been messing around with the gauge temp sensor before as the wire didn't have a plug on the end. The sensor that was in was the correct one YCB100420, though it was shot, reading way out from the RAVE manual specs - reading in the 10s of K ohms. For reference the correct readings on your meter are:
142.0 ohms Wide sector at cold
32.1 to 49.0 ohms 10 degrees below horizontal (engine normal operating temperature)
16.9 ohms Red sector at hot
Wiring diagram in RAVE shows it as a 1000 ohm variable resistor so a relatively high reading expected testing it from cold. You can see although there are two pins in the sensor they are connected together so you test between the sensor body and the pins.
Now the problems came when I tried ordering replacements. ERR2081 was showing as the correct replacement on ebay by various sellers so I ordered one. This is not the correct sensor although everyone seems to think it is!!!
It is a two pin sensor, does not earth through the body and the resistance value is way off - seems to be around 3000 ohms to 300 ohms.
Went to local independent parts place - was sold a WS1120 sensor. Again this sensor is not the correct part, it is a two pin sensor and resistance wildly off. Connector has a slight offset as well so won't plug in.
Ended up going to the local scrapyard and pulling a sensor off an old petrol rover 25. Just a warning - beware that a lot of people are selling these random sensors as compatibles - they aren't compatible with early freelanders! If you have two coolant sensors you must be very careful to check you are getting the right sensor as a lot of computer systems have decided that all K series coolant temp sensors are compatible which they are clearly not. If in doubt, go to the shop with your meter and test it there before you hand over the cash. Hope this saves someone ordering the wrong bits.
