11 replies to this topic

[kwacktastic]

Hi,

A minor fault has recently appeared on my '96 Cooper Mpi. After running normally for fifteen minutes or so, the cooling fan will switch and stay on. I'm assuming at this stage that the cause is likely to be the water temperature transducer which is fitted to the thermastat housing. I was just looking for a replacement on the Minispares website and found it to be part number GTR206. A related product is YMQ105690 which the text claims is a modified item to correct a known fault. Does anyone know what this known fault is and what is different about this connector compared to the standard offering? Specific reference is made to Rover Technical Bulettin 0043 - does anyone have a copy as I can't find one?

Any advice gratefully received. Many thanks,

Kwack

[miniman retford]

I had the same problem with mine a few months ago, I just took the connector off & cleaned the sender & connecting plug with electrical cleaner & had no problems since.

[kwacktastic]

Thanks for the advice - I don't think it'll take too much sorting out, I just wondered what issue the "tech item" related to. I'll give it a once-over once I've finished my week of nights!

Kwack

Edited by kwacktastic, 02 October 2008 - 09:37 AM.

[Elisha-The-Cooper]

lol i have this problem too, but mines comes on streight away

ill follow this advice too

x

[John H]

there is a known problem with the wiring to mpi fans causing them to run continuiously.

or should i say that its a common problem with the wiring

Edited by minimadmotorman, 02 October 2008 - 03:59 PM.

[kwacktastic]

Strange, I wasn't aware of a common problem with the cooling on MPi. Do you know specifically what about it was modified and why? As mine's a '96 model, it'll be one of the first made and I suspect it's the original part. Presumably, these cars were never the subject of a recall by Rover at the time.

My experience (albeit limited) is that it's actually quite a simple and reliable set-up. You can simulate the fan running all the time by pulling the connector off the transducer. The fan starts up immediately as the ECU puts the engine configuration into "safety first" mode. The likely cause of the problem in this situation would be open-circuit wiring (e.g. a break or loose connection), a faulty transducer or connector. Either way it shouldn't be too difficult to fix.

I'd be very interested in any further light that can be shed on this.

Thanks again,

Kwack

[John H]

i think that you hit the nail on the head with the open circuit situation from the temp sender.

from what i remember on my ex's 96 mpi the wiring to the cooling fan was quite stretched. i have heard of this wiring breaking down but it wouldnt cause the symptoms you are experiencing.

[taffy1967]

There really should have been a recall, there certainly was for the rear wheel bearings on the Twin-Points though.

This is the tech bulletin itself: -

Twin-Point/MPi Electric Fan Issue: -
http://matsone.csuea...ges/x8479bu.pdf

[kwacktastic]

Many thanks all - very much appreciated.

Kwack

[kwacktastic]

The problem is now solved and the cause was found to be the thermostat - it wasn't opening fully causing the block temperature to be too high.

This particular aspect of the MPi set-up is poorly designed in my opinion. The water temperature transducer is mounted in a sandwich plate between the head and the thermostat housing. This is fine all the time all the components are working as expected. If however the thermostat fails to open (as is prone to happen as they age) the block temperature will rise as it's not possible to divert water through the radiator to aid cooling. The sensor detects the high block temperature and turns the electric fan on. This of course has very little effect as there's no hot water being passed through the radiator! Why didn't they fit a seperate transducer to the bottom of the radiator? - then, if the radiator water gets too hot, the fan will operate and have a useful effect.

I guess my thermostat may have been "iffy" for a while as the fan would operate frequently when in stop-start traffic etc. Since the new 88C thermostat has been fitted, it hasn't operated once!

Anyhow, hope this is of use to anyone with cooling issues on an MPi.

Kwack.

Edited by kwacktastic, 09 October 2008 - 10:15 PM.

[taffy1967]

Glad it's sorted mate.

[fuji0010]

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