1.6 K-Series fan control switch
Discussion
I daily an MG ZS with the 1.6 K-Series engine. Touch wood(!) it's never overheated in 6 months of my ownership and 5,000 miles covered (now on 45,600).
The problem is the fan never comes on, even in the extreme heat we had a week or two ago, but when driving around in stop start traffic the engine does seem to smell a touch hot, from the outside at least.
The temp gauge shows that the car gets up to temperature really quickly - although my friendly local tells me that when the gauge settles below the half way point (it's default position) the temperature reading is actually 90 degrees when measured with their equipment.
The garage were able to get the fan running momentarily today when bypassing the fan control switch - so think the problem may lie there, albeit they fear there may be a problem with the wiring as well as the fan did not stay on.
The garage however were unable to locate a new fan control switch today, and don't have a part number. Google throws up a few different possibilities.
Can the PH collective help? Is it the part same across the 1.4, 1.6 and 1.8 K-Series? Where might I find one? Confusingly, they mentioned both a fan control switch and sensor - is this the same thing?!
The problem is the fan never comes on, even in the extreme heat we had a week or two ago, but when driving around in stop start traffic the engine does seem to smell a touch hot, from the outside at least.
The temp gauge shows that the car gets up to temperature really quickly - although my friendly local tells me that when the gauge settles below the half way point (it's default position) the temperature reading is actually 90 degrees when measured with their equipment.
The garage were able to get the fan running momentarily today when bypassing the fan control switch - so think the problem may lie there, albeit they fear there may be a problem with the wiring as well as the fan did not stay on.
The garage however were unable to locate a new fan control switch today, and don't have a part number. Google throws up a few different possibilities.
Can the PH collective help? Is it the part same across the 1.4, 1.6 and 1.8 K-Series? Where might I find one? Confusingly, they mentioned both a fan control switch and sensor - is this the same thing?!
MG ZS seems to be a relatively new car ?
Unless China are really building them in an archaic manner, the chances of actually having the fans controlled by a separate switch, is very unlikely.
Most cars for the last couple of decades the ecu controls the fans based on the temperature sensor. Not a separate switch.
But if it is not overheating, there can't really be much of a problem
Unless China are really building them in an archaic manner, the chances of actually having the fans controlled by a separate switch, is very unlikely.
Most cars for the last couple of decades the ecu controls the fans based on the temperature sensor. Not a separate switch.
But if it is not overheating, there can't really be much of a problem
I'm pretty sure a MG Rover of that vintage will have an ECU controlled fan using the engine coolant temperature sensor rather than a thermoswitch screwed into the radiator. Worth starting with the relay and fuse for the cooling fan, both should be in the fuse box. If the fuse has blown, ensure the fan motor spins freely, bearings can dry up and cause the motor to seize or partialy seize with age.
Thank you for the replies.
I've spun the fan with my finger (car switched off!!!) and it does seem to spin freely, and I'll have a look at the fuses when I get the car home later.
I wonder if there's a bit of confusion being caused by the mechanic's choice of language? He'd originally said "sensor" then repeatedly said "switch" (I asked him again as I was taking a note).
The mechanic worked for the local MG Rover dealer back when these were new so, has changed lots of head gaskets on these units. I'm inclined to think this one has an upgraded head fitted as I - so far - have had no trouble.
The wee MG is due an MOT shortly and given that this chap will be doing the test I do understand why he doesn't want the car to be sitting idling, knowing that the fan won't kick in if things start to get hot....he said they'd be liable if it went 'pop'. When they were investigating today apparently the temp was climbing towards 100 degrees, but again I've never had it overheat on me and there's no visible sign of mayo on the oil cap or anything like that.
I've spun the fan with my finger (car switched off!!!) and it does seem to spin freely, and I'll have a look at the fuses when I get the car home later.
I wonder if there's a bit of confusion being caused by the mechanic's choice of language? He'd originally said "sensor" then repeatedly said "switch" (I asked him again as I was taking a note).
The mechanic worked for the local MG Rover dealer back when these were new so, has changed lots of head gaskets on these units. I'm inclined to think this one has an upgraded head fitted as I - so far - have had no trouble.
The wee MG is due an MOT shortly and given that this chap will be doing the test I do understand why he doesn't want the car to be sitting idling, knowing that the fan won't kick in if things start to get hot....he said they'd be liable if it went 'pop'. When they were investigating today apparently the temp was climbing towards 100 degrees, but again I've never had it overheat on me and there's no visible sign of mayo on the oil cap or anything like that.
K-series engines have 2 coolant temp sensors. One for the ECU & fan and one for the temp gauge.
Items 14, & 16 are the coolant sensors. It suggests item 16 is the ECU sensor, as item 14 says 'gauge' in the description.
https://rimmerbros.com/Item--i-GRID003186
Items 14, & 16 are the coolant sensors. It suggests item 16 is the ECU sensor, as item 14 says 'gauge' in the description.
https://rimmerbros.com/Item--i-GRID003186
MGSteve said:
K-series engines have 2 coolant temp sensors. One for the ECU & fan and one for the temp gauge.
Items 14, & 16 are the coolant sensors. It suggests item 16 is the ECU sensor, as item 14 says 'gauge' in the description.
https://rimmerbros.com/Item--i-GRID003186
That's massively helpful - thank you loads - that's hugely appreciated....!!!! Items 14, & 16 are the coolant sensors. It suggests item 16 is the ECU sensor, as item 14 says 'gauge' in the description.
https://rimmerbros.com/Item--i-GRID003186
That's quite normal
And the mechanic may be confused as to what a sensor is and a switch is. But they are distinctly different things.
However, often unplugging the ecu temperature sensor can default the ecu into a limp mode of sorts as it knows it is unplugged and this could very likely bring the fan on if it works.
Or at least offer you a chance to check if the relay is triggered, and if there is power going to the fan.
And the dash gauge is rarely accurate, best to get a scan tool and see what the ecu is actually reading in terms of temperature.
And the mechanic may be confused as to what a sensor is and a switch is. But they are distinctly different things.
However, often unplugging the ecu temperature sensor can default the ecu into a limp mode of sorts as it knows it is unplugged and this could very likely bring the fan on if it works.
Or at least offer you a chance to check if the relay is triggered, and if there is power going to the fan.
And the dash gauge is rarely accurate, best to get a scan tool and see what the ecu is actually reading in terms of temperature.
stevieturbo said:
That's quite normal
And the mechanic may be confused as to what a sensor is and a switch is. But they are distinctly different things.
However, often unplugging the ecu temperature sensor can default the ecu into a limp mode of sorts as it knows it is unplugged and this could very likely bring the fan on if it works.
Or at least offer you a chance to check if the relay is triggered, and if there is power going to the fan.
And the dash gauge is rarely accurate, best to get a scan tool and see what the ecu is actually reading in terms of temperature.
Interestingly enough, upon picking the car up tonight, I turned on the ignition without turning over the engine and the fan started spinning. Started the engine, fan spinning.And the mechanic may be confused as to what a sensor is and a switch is. But they are distinctly different things.
However, often unplugging the ecu temperature sensor can default the ecu into a limp mode of sorts as it knows it is unplugged and this could very likely bring the fan on if it works.
Or at least offer you a chance to check if the relay is triggered, and if there is power going to the fan.
And the dash gauge is rarely accurate, best to get a scan tool and see what the ecu is actually reading in terms of temperature.
I drove the car home - only about a mile or so - and the temperature gauge was, as expected, sitting where it does normally, just below halfway. I kept the engine running as the car sat on the drive and the fan is still spinning away. Connected to the ECU being in that limp mode of sorts, as you had posted above?
The quick heating is normal - one of the benefits of the K Series is hot heaters before leaving my road...!
YCB100420 does the gauge (blue plug) and MEK000030 does the ECU (inc fans - black plug).
Unplug the MEK000030 and see what happens - both sensors are on the coolant outlet elbow on the right-hand side of the engine when looking at it from the front.
I help run one of the more prominent MG Rover specialists (but don't believe I can say who) and these days we do sell a lot of both sensors - they're at an age where they do just give up.
YCB100420 does the gauge (blue plug) and MEK000030 does the ECU (inc fans - black plug).
Unplug the MEK000030 and see what happens - both sensors are on the coolant outlet elbow on the right-hand side of the engine when looking at it from the front.
I help run one of the more prominent MG Rover specialists (but don't believe I can say who) and these days we do sell a lot of both sensors - they're at an age where they do just give up.
As above, they are a common pair of sensors across all engines, one for the gauge, the other for the ECU . It’s not uncommon for the wiring to deteriorate and fracture internally on some of the connections, the temp sensors are one such area and the throttle position sensor is another, I have a bunch of those sensors kicking around, a sensible approach might be to swap the two wire sensor out and see how it fares. However, If the sensor is faulty I would expect you to experience other issues as the ECU will be seeing incorrect engine temperatures and may well be making adjustments to fuelling/timing etc. according to its calibration.
Dave
Dave
mattyprice4004 said:
The quick heating is normal - one of the benefits of the K Series is hot heaters before leaving my road...!
YCB100420 does the gauge (blue plug) and MEK000030 does the ECU (inc fans - black plug).
Unplug the MEK000030 and see what happens - both sensors are on the coolant outlet elbow on the right-hand side of the engine when looking at it from the front.
I help run one of the more prominent MG Rover specialists (but don't believe I can say who) and these days we do sell a lot of both sensors - they're at an age where they do just give up.
Thank you...!! I've seen genuine MG Rover and aftermarket items listed, like in the link posted by MG Steve. Do you think it's worth the extra few quid to go with genuine parts? These ones have lasted 19 years - so great service - but don't want to spend the extra if it wasn't required.YCB100420 does the gauge (blue plug) and MEK000030 does the ECU (inc fans - black plug).
Unplug the MEK000030 and see what happens - both sensors are on the coolant outlet elbow on the right-hand side of the engine when looking at it from the front.
I help run one of the more prominent MG Rover specialists (but don't believe I can say who) and these days we do sell a lot of both sensors - they're at an age where they do just give up.
DVandrews said:
As above, they are a common pair of sensors across all engines, one for the gauge, the other for the ECU . It’s not uncommon for the wiring to deteriorate and fracture internally on some of the connections, the temp sensors are one such area and the throttle position sensor is another, I have a bunch of those sensors kicking around, a sensible approach might be to swap the two wire sensor out and see how it fares. However, If the sensor is faulty I would expect you to experience other issues as the ECU will be seeing incorrect engine temperatures and may well be making adjustments to fuelling/timing etc. according to its calibration.
Dave
Thanks Dave - great stuff, appreciate your comment.Dave
Certainly no other issues as far as I can tell - 43mpg, so not over-fueling and she seems to run really sweetly.
Brodz said:
Interestingly enough, upon picking the car up tonight, I turned on the ignition without turning over the engine and the fan started spinning. Started the engine, fan spinning.
I drove the car home - only about a mile or so - and the temperature gauge was, as expected, sitting where it does normally, just below halfway. I kept the engine running as the car sat on the drive and the fan is still spinning away. Connected to the ECU being in that limp mode of sorts, as you had posted above?
So you are now saying there is a new "fault", in that the fan is now running all the time ? Whether it is an actual fault, or something someone has created ?I drove the car home - only about a mile or so - and the temperature gauge was, as expected, sitting where it does normally, just below halfway. I kept the engine running as the car sat on the drive and the fan is still spinning away. Connected to the ECU being in that limp mode of sorts, as you had posted above?
stevieturbo said:
So you are now saying there is a new "fault", in that the fan is now running all the time ? Whether it is an actual fault, or something someone has created ?
The mechanic took the sensor (now known to be MEK000030 - thanks guys!) out and bypassed it, after which he tells me the fan ran - but only for a few seconds.He then put everything back together as it was - so the sensor is back in place. Now the fan spins up when you turn the ignition key then spins continuously when the engine is actually started.
Presumably the fan should only kick in when the coolant gets to X degrees.
......I'm going to order sensors and replace them for good measure.
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