rad fan not working

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There isn't an oil temperature switch on the puma. The oil sensor under the inlet manifold works on pressure not heat.
 
Methinks Pumanoob mistook old temperature sensor for oil temperature sensor
Methinks I do too much methinking though :roll:
 
Doh, I'm reading the posts on my phone, in the car (I'm not driving), but I thought sparkies post said he was checking the resistance on the oil temp sensor. I've just looked back and it sats "old" temp sensor not "oil" temp sensor!!! I really should have paid more attention in school!!

Sorry all for confusing the thread even more!!!
 
Lol, nobody told me the pic link hadnt worked!!! :oops:

Here is the coolant temp sensor and gauge sender pic.

TempSensordiagram-1.jpg


The resistor values are as follows for 1 wire sender sensor

0 degrees = 120 ohms
50 degrees = 25 ohms
100 degrees = 10 ohms

Those are a rough reading
The resistance values you got from yours are WAY off if it was the 2 wire sensor you tested!
 
Thanks PumaNoob!

It was the two wire sensor I tested. Albeit the old one I took out.

So you've posted the readings for the one wire... I'll do a comparison on mine.
Does the one wire sensor ground on the block?

Do you know what readings/resistance we should get on the two wire?

Is the picture you posted a Puma engine? That's quite interesting to look at. The 'gauge' sensor is lower than the one for the ECU. I have readings on the dash, so the coolant is obviously sloshing over that sensor. Maybe I have an airlock in this area? But, that would seem weird though because as far as I'm aware, the rad fan has never worked (since I've had the car at least). Surely I couldn't have had an air lock for almost 2 years..!?
 
That's it, the 1 wire grounds on the block.

I posted the 2 wire values earlier, but here they are again

0 degrees = around 1700 ohms
70degrees = around 460ohms.
100 degrees = around 200ohms.
So your readings from your 2 wire were way off the mark!
 
Sorry, I thought you posted them earlier, but I can't see them... :oops:

Yes, my readings are off a bit, but like I said, it was the old one! I'm going to pull the new, two wire one out of the car and see what that gives me. Do I need to be concious of which way round/polarity when I test them?

EDIT... found the values you posted earlier... :oops:
 
I just checked it at the polarity it's wired to the engine. But to be honest I don't know if polarity matters when checking the resistance. My values could be a little off, but not by much, let me know what you come up with.
 
Right guys need to get in on this one....

My fan does not come on yet the temp gauge never gets past the mid-point, put the aircon on and fan comes on (low speed) run a power wire direct to the fan and it comes on (obviously).

Is the Puma engine very efficient at cooling itself? if so I will leave it alone.

Wondering though to be on the safe side about wiring the fan to a switch on the dash to give me control should it be needed, or just hit the aircon button if temp goes up.

Slightly off topic (sorry) how much power does the aircon sap from the engine, if any?
 
I never have the rad fan come on unless im sitting in traffic for a long time on a hot day, so i would say the puma is quite efficient at keeping the engine cool. Did you try pulling the plug off the coolant temp sensor like i suggested? If the rad comes on, then youve probably not got a problem, its coming up to temperature and the thermostat is controlling it.
 
Weird one this....

I replaced the thermostat housing a few weeks ago as it was leaking.
Today I've drained water out and shoved in 3ltr of antifreeze.

While I was running the engine to get the air-locks out, the temp gauge was reading between 'A' & 'L' and the rad fan came on!

No idea whether it was a fluke or not... but going to keep an eye on it...
 
Got the engine temp hot enough to push the gauge past the 'L' and no fan on.. :evil:
 
I'm having the same problem! But my fan won't even come on when air con is on! Is that fuse? And if so is it fuse box under bonnet or drivers side? And bonnet ones... How are they numbered? Many thanks!
 
This issue was never resolved as the fault could not be traced.

The relays are in the fuse box under the bonnet.

I'm pretty sure someone has posted on here the details of the fuse layouts....
 
PumaNoob said:
Is your car driving ok, fuelling ok ect? It could be the coolant temp sensor not working. To check it, put the key in the ignition, turn to position 2, then unplug the coolant sensor plug (located under the coil pack in the water outlet). The fan should come on straight away. If it doesn't, it's wiring between the sensor and fan. If it does come on, then the sensor is gone and needs replacing.
having the same problem, this did not work as you described.
I had to start the engine and then unplug the plug. within seconds it came on and within a few more it kicked into high.
So I guess my sensor is gone as well.
 

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