Quick question about fan and ECT sensor/switch

[kento16us]

I plan to change the water pump while changing the timing belt. Since I'm going to stick with Toyota's expensive red coolant, I plan on changing the ECT sensor and the Fan sensor/switch (the one on the bottom of the radiator).

Is the Fan sensor/switch the same sensor as the ECT? So I just purchase 2 ECT sensors? Most of the auto sites don't mention or have a switch/sensor for the fan listed. I found the stock part number and the OEM price is close to $80.

Anyone know?

[bronzemaxell]

ECT sensor is the one feeding engine ECU, not the gauge on dash

coolant temp sensor at the bottom of radiator is for the guage on dash.

[JohnGD]

Is there a reason you want to replace the ECT sensor and the fan switch? They can be changed later. And no, they are different. One is a resistor telling the ECU the coolant temperature. The other is just a switch that turns on/off based on coolant temperature. Make sure you get the right ones on rockauto.com.

However, if you do the pump and timing belt, I'd recommend a complete job:

an earlier list from rockauto.com:
GATES TCK199 (kit of timing belt with two pulleys and instruction)
$84.79
GATES Part # K030295 PS belt $4.32
GATES Part # K050435 Alt/AC $12.12
FEL-PRO TCS45641 Cam seal $4.11
FEL-PRO TCS45920 Crank seal $6.04
BCA Part # 221820 Oil pump seal $2.71
AISIN (Toyota #16110-79185) water pump $58.79
FEL-PRO VS50304R valve cover gasket set $13.94

www.gates.com
www.ngksparkplugs.com
www.akebonobrakes.com

Originally Posted by kento16us

I plan to change the water pump while changing the timing belt. Since I'm going to stick with Toyota's expensive red coolant, I plan on changing the ECT sensor and the Fan sensor/switch (the one on the bottom of the radiator).

Is the Fan sensor/switch the same sensor as the ECT? So I just purchase 2 ECT sensors? Most of the auto sites don't mention or have a switch/sensor for the fan listed. I found the stock part number and the OEM price is close to $80.

Anyone know?

[kento16us]

I know the differences between the ECT sensor and the fan switch. The main problem was finding the right switch for the fan, as well as the sender for the gauge (unless that goes off one of the two). Since im going with the 30 dollar red toyota coolant, I prefer not having to change these parts down the road when I can get them for around $30 or less. Due to having to drain the coolant to change these parts (especially the one at the bottom of the radiator).

Since the car has close to 100k, its better to do it now then have to deal with it later. I believe I have found both parts through rockauto and other sites as well.

Also plan to change the parts as JohnGD listed.

[JohnGD]

Understood. You may also want to double check using O'Reilly, Beck Arnley, Delco, and Autozone's online catalog.

I'm not as certain what some of those remarks on rockauto.com's list mean, and I'm not sure what setup you have.

All the best!

www.beckarnley.com
http://www.acdelco.com/parts/index.jsp

Originally Posted by kento16us

Since im going with the 30 dollar red toyota coolant, I prefer not having to change these parts down the road when I can get them for around $30 or less. Due to having to drain the coolant to change these parts (especially the one at the bottom of the radiator).

[sintox]

Hi JohnGD,
Your answer made sense to me:
"One is a resistor telling the ECU the coolant temperature. The other (bottom right of radiator) is just a switch that turns on/off based on coolant temperature."
I believe the resistor-one name is Coolant Temperature Sensor CTS.

Now I have a question: Which one controls the gauge-needle on the dash ? (CTS or something else, but certainly not the one at the bottom of Radiator because a resistor is needed for the needle).

[stuckTaco]

You guys have it all wrong. The one on the radiator is for the fan. It kicks the fan on at certain temp. The one on the head/housing is for the needle. Unplug the one on the radiator and jump it with a paper clip, your fan should kick on.

[sintox]

Yeah, I think that's correct.

I'm going to change that fan-switch sometime in the future and keep the CTS (the other coolant temp. sensor).

By the way, anyone bought a rad-fan-switch and know a place with cheap shipping to Canada ?

Thank you.

Originally Posted by stuckTaco

You guys have it all wrong. The one on the radiator is for the fan. It kicks the fan on at certain temp. The one on the head/housing is for the needle. Unplug the one on the radiator and jump it with a paper clip, your fan should kick on.

[JohnGD]

The coolant temperature "sender" is a one-wire deal (the temperature sensor is a two-wire deal). Should be on the inlet housing on the driver side of the engine.

Temperature sender (to the gauge):
AIRTEX Part # 1T1166 $14.55USD + shipping
http://www.rockauto.com/catalog/moreinfo.php?pk=942445

Originally Posted by sintox

Hi JohnGD,
Now I have a question: Which one controls the gauge-needle on the dash ? (CTS or something else, but certainly not the one at the bottom of Radiator because a resistor is needed for the needle).

[sintox]

Ok Thank John.

So there are 3 different deals, if I understand you:
1) Fan-Switch (bottom of rad). I know this one.
2) Cooland Temp. sensor (near top of engine). I also know this one, it has a green connector inside).
and,
3) Temperature "sender" (inlet housing on the driver side).

Originally Posted by JohnGD

The coolant temperature "sender" is a one-wire deal (the temperature sensor is a two-wire deal). Should be on the inlet housing on the driver side of the engine.

Temperature sender (to the gauge):
AIRTEX Part # 1T1166 $14.55USD + shipping
http://www.rockauto.com/catalog/moreinfo.php?pk=942445

[stuckTaco]

I have yet to see a bad temp sensor. All it does create more resistance based on temp (heat) and grounding it out to the car body/chassis. Unless your the gauge is fubar where the needle reads really low or super high. I be more worried with the fan switch sensor instead.