Overheating (Update Post 35, please help!)

[bildo]

Coolant Temperature Sensor

It's generally the resistors that go, you can buy a nime box LINK ECP will sell good parts.

If I was to buy new fans, would the resistors get replaced? Am I taking a gamble forking out for them or would you generally assume it would fix the problem? Pretty bored of messing about with it now, he's going to need it til Monday to do this alone so I'll have to get the bus to work in the meantime which is hardly fun!

 

[LEE69]

Resistors are built into the fans.
All the symptoms point to the resistors, how you go about fixing it is down to you, the nime box is the cheapest way.

 

[chris c]

Are you sure its getting hot and its not just a faulty sensor? Odd that you're now getting cold readings as well. Ask the guy in the garage if he's considered the sensor. You can get the actual water temp through the climate control panel which uses a different sensor. Theres a guide on how to do that on here somewhere

 

[LEE69]

How to read the climate control

http://lee69.co.uk/Car stuff/Leon/codes.txt

 

[bildo]

Are you sure its getting hot and its not just a faulty sensor? Odd that you're now getting cold readings as well. Ask the guy in the garage if he's considered the sensor. You can get the actual water temp through the climate control panel which uses a different sensor. Theres a guide on how to do that on here somewhere

Well the fact that it was reaching those temps without the fans even considering kicking in and the air con being on without either of the fans bothering to turn whatsoever I will assume it's not down to a sensor.

Would I be wrong here? I'm not dismissing your advice at all, I fully welcome it, just wondering if those symptoms match.

Lee, thanks a lot for the guide I'll pass it on.

Cheers guys!

 

[mty12345]

re:fan check

Just looked up your fan issue in the seat workshop manual, and this is how to test if it's the fans themselves(unlikely in my opinion) the wiring to the fans, or some other part of the cooling system at fault(maybe thermostat or the fan switch sensor that the following connector attaches too etc)...... I've added my own bits in (CAPS) to try and clarify stuff for you.....
(CHECK ALL FUSES AND RELAYS FOR THE FANS ARE OK FIRST, BUT I TAKE IT THEY MUST OF CHECKED THOSE FOR YOU ALREADY)
Cooling system components: removing and installing
Radiator fans: checking

Checking process

‒ → Remove 3 pin connector from radiator fan thermoswitch(THIS IS ON THE BACK OF YOUR RADIATOR AT THE BOTTOM CORNER, ON THE PASSENGER SIDE).

‒ Switch on ignition.

(THIS IS IMPORTANT BUT HARD TO DESCRIBE, SO BARE WITH ME THE 3 PINS ARE AS FOLLOWS,HOLD THE CONNECTOR FACING YOU SO YOUR LOOKING AT THE PINS......ONE SIDE OF THE TRIANGLE CONNECTOR HAS A FLAT PROTRUDING BIT......., THIS NEEDS TO BE ON THE RIGHT HAND UPPER SIDE OF THE TRIANGLE (2'O'CLOCK)AS YOU LOOK AT IT)......(WITH IT IN THIS POSITON..PIN 1: IS THE TOP ONE, PIN 2: IS THE BOTTOM RIGHT, PIN 3: IS THE BOTTOM LEFT)

‒ Bridge contacts -1- and -2- of the connector terminal using AN auxiliary cable (ANY PIECE OF HOUSEHOLD WIRE WITH SOME PLASTIC INSULUTION AND TWO STRIPPED ENDS WILL DO). Radiator fans should begin to run at speed 1.

‒ Bridge contacts -2- and -3- of the connector terminal using auxiliary cable again
. Radiator fans should begin to run at speed 2.

If fans do not run at 1st or 2nd speeds:

Check wiring to fans:

If no wiring fault is detected:

‒ Replace radiator fans !
(I THINK YOUR FANS WILL PROBABLY RUN MYSELF, IF THEY DO, AND IT WAS MY CAR, THE 1ST THING I WOULD DO IS CHANGE THE THEROMSTAT, WHEN THEY START TO FAIL THEY WILL RANDOMLY STICK CLOSED, WHICH WILL STOP YOUR FANS TURNING ON BECAUSE ALTHOUGH THE COOLING SYSTEM IS OVERHEATING, ITS DOING SO BECAUSE THE WATER IS BYPASSING YOUR RADIATOR. THIS WILL MEAN THAT THE WATER IN YOUR RADIATOR IS STILL COLD AND THE FANS WON'T SWITCH ON BECAUSE THEY MEASURE THE TEMP IN THE RADIATOR WATER!!! NOT THE ENGINE WATER!!!![EVEN THOUGH THE ENGINE IS STEAMING ETC) wOULD ALSO EXPLAIN WHY IT WAS STAYING COLD (60C) THAT ONE TIME BECAUSE SOMETIMES THEY WILL RANDOMLY STICK OPEN TOO, THIS WILL MEAN WATER GOING THROUGH THE RADIATOR BEFORE THE ENGINE HAS HEATED UP CAUSING IT THEY STAY AT AROUND THE 60C MARK

THEMOSTAT WILL BE ABOUT £5-£10 QUID FROM YOUR LOCAL HALFORDS ETC AND IS EASY ENOUGH(1HOURS LABOUR) TO CHANGE FOR ANY GARAGE.
HOPE ALL THAT HELPS YOU OUT, GD LUCK

 

[bildo]

Just looked up your fan issue in the seat workshop manual, and this is how to test if it's the fans themselves(unlikely in my opinion) the wiring to the fans, or some other part of the cooling system at fault(maybe thermostat or the fan switch sensor that the following connector attaches too etc)...... I've added my own bits in (CAPS) to try and clarify stuff for you.....
(CHECK ALL FUSES AND RELAYS FOR THE FANS ARE OK FIRST, BUT I TAKE IT THEY MUST OF CHECKED THOSE FOR YOU ALREADY)
Cooling system components: removing and installing
Radiator fans: checking

Checking process

‒ → Remove 3 pin connector from radiator fan thermoswitch(THIS IS ON THE BACK OF YOUR RADIATOR AT THE BOTTOM CORNER, ON THE PASSENGER SIDE).

‒ Switch on ignition.

(THIS IS IMPORTANT BUT HARD TO DESCRIBE, SO BARE WITH ME THE 3 PINS ARE AS FOLLOWS,HOLD THE CONNECTOR FACING YOU SO YOUR LOOKING AT THE PINS......ONE SIDE OF THE TRIANGLE CONNECTOR HAS A FLAT PROTRUDING BIT......., THIS NEEDS TO BE ON THE RIGHT HAND UPPER SIDE OF THE TRIANGLE (2'O'CLOCK)AS YOU LOOK AT IT)......(WITH IT IN THIS POSITON..PIN 1: IS THE TOP ONE, PIN 2: IS THE BOTTOM RIGHT, PIN 3: IS THE BOTTOM LEFT)

‒ Bridge contacts -1- and -2- of the connector terminal using AN auxiliary cable (ANY PIECE OF HOUSEHOLD WIRE WITH SOME PLASTIC INSULUTION AND TWO STRIPPED ENDS WILL DO). Radiator fans should begin to run at speed 1.

‒ Bridge contacts -2- and -3- of the connector terminal using auxiliary cable again
. Radiator fans should begin to run at speed 2.

If fans do not run at 1st or 2nd speeds:

Check wiring to fans:

If no wiring fault is detected:

‒ Replace radiator fans !
(I THINK YOUR FANS WILL PROBABLY RUN MYSELF, IF THEY DO, AND IT WAS MY CAR, THE 1ST THING I WOULD DO IS CHANGE THE THEROMSTAT, WHEN THEY START TO FAIL THEY WILL RANDOMLY STICK CLOSED, WHICH WILL STOP YOUR FANS TURNING ON BECAUSE ALTHOUGH THE COOLING SYSTEM IS OVERHEATING, ITS DOING SO BECAUSE THE WATER IS BYPASSING YOUR RADIATOR. THIS WILL MEAN THAT THE WATER IN YOUR RADIATOR IS STILL COLD AND THE FANS WON'T SWITCH ON BECAUSE THEY MEASURE THE TEMP IN THE RADIATOR WATER!!! NOT THE ENGINE WATER!!!![EVEN THOUGH THE ENGINE IS STEAMING ETC) wOULD ALSO EXPLAIN WHY IT WAS STAYING COLD (60C) THAT ONE TIME BECAUSE SOMETIMES THEY WILL RANDOMLY STICK OPEN TOO, THIS WILL MEAN WATER GOING THROUGH THE RADIATOR BEFORE THE ENGINE HAS HEATED UP CAUSING IT THEY STAY AT AROUND THE 60C MARK

THEMOSTAT WILL BE ABOUT £5-£10 QUID FROM YOUR LOCAL HALFORDS ETC AND IS EASY ENOUGH(1HOURS LABOUR) TO CHANGE FOR ANY GARAGE.
HOPE ALL THAT HELPS YOU OUT, GD LUCK

Great help, and nice and newbie friendly for me, thanks!

I have forwarded this onto the garage to double check he has definitely checked all this before proceeding.

I really appreciate your time and effort, top man

 

[chris c]

keep us posted mate. Hope it gets sorted soon and I'd be interested in the outcome. Something tells me it's not as simple as we all think as I would have thought any mechanic worth his salt would have checked these things. Hope it is though

 

[mty12345]

re:fan check

No worries mate, you're welcome. Let us know what it turns out to be, hopefully nothing serious

 

[RabReith89]

Hi mate have u had any luck? Am having the exact same problem and
Issues with my cupra r

Thanks Rab