Have a 2.2 Townace with newly fitted 3CT engine. There was a clicking noise coming from under the dashboard, located it to a plug of some kind, and noticed that when I unplugged it a fan noise (not the viscous fan)stopped, together with the clicking (which I could feel as the plug vibrating). The mechanic who put the new engine in says it is the thermostat/controller which is screwed into a place near where the radiator filler neck is. There is a connector attached to this thermostat, which again by unplugging stops the fan. So the problem seems to be that the fan is coming on nearly all the time (particularly in the first 5 mins after starting the engine). What I would like to find is what the part number of the thermostat (or controller if that is what it is called) because he was not able to find this out from Toyota - they faxed through something completely different. Thanks.

- (#5611) Bill Jones, 24 Sep 02

The fan that appears to stop when you unplug this connector, where is it, do you mean the heater fan under the dash infront ofthe pssennger? or do you mean the main electric fans on the horizontal radiator/air con condenser. If it is the interior fan, then I also ask if you have climate control on your car (numbers on the temp control & 'auto' on the fan controller) if it is climate control then it could be controlling the interior fan in a funny way now we have colder weather. Let me know some more info as above & I'll try to help you further. Regards Rob.

- (#5612) Rob Drinkwater, 24 Sep 02

If the fans are on at full speed, he's got the two sensors on the filler neck reversed (and your aircon isn't working...
(I presume you've a 4x4 auto)

- (#5613) david miller, 24 Sep 02

OK. This fan comes on as soon as the key turns the electrics on (before ignition). It isn't the heater/blower fan, and the air con works fine. From reading Ace answers I deduced that it was the horizontal fans over the radiator (although I couldn't actually see them). My previous 3CT engine was completely wrecked, so I bought another one and had it fitted. The sensor screws into one of 2 holes on a box at the base of the filler neck, the one nearest the filler neck, the other hole being blanked off. Removing the connector to the sensor stops the fans. When the engine was changed the mechanic commented that the sensor seemed a bit discoloured and could have been damaged by the original overheating problem. However I have to say (touch wood) that I am now not losing a drop of water and have had no heating problems
so perhaps better the fan is on all the time than never on at all, although his comment was there was a danger of the fan motor burning out.
My car is a 93 Townace auto 4x4 with a 3CT engine.

- (#5655) Bill Jones, 25 Sep 02

That's odd, 4x4 autos normally have two sensors- one (112c, normally closed) to disable the aircon at high temps, the other (105c, normally open) turns the fans on at full speed before that. Perhaps the wrong sensor has been fitted? They are marked on the flats of the hex with a code and a temperature.

- (#5656) david miller, 25 Sep 02

Sure it's not the fans that have been wired wrong way round so they are permanently on. It sounds suspiciously like the problem I had after my head rebuild.

- (#5657) Ian Dunse, 25 Sep 02

The thermostat has 2 markings
an N in a circle on one flat, and 103 on another flat. On top there is a 1/4 inch spade tag which the connector plugs on to.Does this help narrow down a part number ? Is there any way I can test it in situ ? Or alternatively how can I test whether the fan is wired the wrong way round ?
Thanks.

- (#5658) Bill Jones, 25 Sep 02

When I placed the +ve meter lead to the spade tag, and the -ve end to a nearby chassis point, got a reading of about 3 Ohms (ie nearly a short) and no voltage. When I then switched on the electrics so this fan came on, the resistance measured increased to about 700 Ohms (the meter stopped making the noise detecting a short)and there was a voltage of around 0.6 volt.
Does this help ??

- (#5659) Bill Jones, 25 Sep 02

sounds like a duff switch. 3ohms is too high for a good contact, and 103c sounds right for the N/O switch.
the only test would be to remove it and heat it while checking continuity. I'll bet it doesn't change.
Part numbers I can't really help with as my cd only goes up to the 92 facelift, but it'll be either 89428-28050 or 28060. Can't tell which is which. You might get the dealer to order both, and buy the correct one...

- (#5660) david miller, 25 Sep 02

I've been a bit slow but the local Toyota dealer looked up the part (given the chassis and model numbers)which was 88620-28030, cost is £32.39 + VAT but is unfortunately not a stock item. Are there any equivalent alternatives which might be available in the UK ?

- (#5769) Bill Jones, 9 Oct 02

Nearest I've ever got, and I've fitted one in my own to cool things down a bit, is the Lucas SNB794 item (or equivalent), originally for Daihatsu Charade Diesel. Fitment is interchangeable, but the switching point is 100-95c rather than the toyota items 103- 98c or so. It's about £18 I think.

- (#5770) david miller, 9 Oct 02

Have a 1988 Townace Master Ace Surf 2.0DT. My interior fan heater packed up, when I had it on few weeks ago. Had it on full blast on a hot day with the air con switched on but whilst it was running it just stopped & now the fan does not work at all, which we need for the internal heat blowers. Have checked all the fuses to the right of and beneath the glove box and they look OK. What could it be? Are there any other fuses or relays etc.. that I need to check ? Please help we are very cold

- (#5809) Joe Vinci, 10 Oct 02

circuit breakers in the same general area. stick a pin in the 'ole to reset.

- (#5810) david miller, 10 Oct 02

Have a 1988 Townace Master Ace Surf 2.0DT. My interior fan heater packed up, when I had it on few weeks ago. Had it on full blast on a hot day with the air con switched on but whilst it was running it just stopped & now the fan does not work at all, which we need for the internal heat blowers. Have checked all the fuses to the right of and beneath the glove box and they look OK. What could it be? Are there any other fuses or relays etc.. that I need to check ? Please help we are very cold

- (#5811) Joe Vinci, 10 Oct 02