Direct Power Supply To The Radiator Fan.

[DUMINDU]

hi dear all.

i got a tercel EL40 car. when i bought the the power supply has been given directly to the radiator fan, so that when ever i turn on the car the radiator fan starts to work. the heat indicator also rise not mre than 5 degrees roughly. can you please help me in this?

[Miyuru Daminda]

Directly connecting power supply to radiator fan is the cheap and bad solution for thermostat or relay failure of cooling system. When u do this engine will cool more than required and will not reach the correct operating temperature. Running a engine with low temperature will reduce the fuel efficiency and increase engine wear. so better to fix it as soon as possible.

I don't think it will cost much.

[GuruG]

Directly connecting power supply to radiator fan is the cheap and bad solution for thermostat or relay failure of cooling system. When u do this engine will cool more than required and will not reach the correct operating temperature. Running a engine with low temperature will reduce the fuel efficiency and increase engine wear. so better to fix it as soon as possible.

I don't think it will cost much.

Not only that it will kill the fan motor. Fix it ASAP, as this is not a long term solution and can end up costly.

[tharindu6]

i have a similar question...my A/C fan starts whenever i switch on the A/C...

as far as i know that is not the correct way..will it harm my engine

[Ruslan]

i have a similar question...my A/C fan starts whenever i switch on the A/C...

as far as i know that is not the correct way..will it harm my engine

Guess the A/C fan (think you mean the Condenser fan here) works when the A/C compressor start to work. both A/C compressor and Condenser fan should turn itself off when the thermostat in Evaporator coil reach its temperature. (Something similar to House Air conditioners)

Edited February 14, 2009 by Ruslan

[harshansenadhir]

i have a similar question...my A/C fan starts whenever i switch on the A/C...

as far as i know that is not the correct way..will it harm my engine

Normal, however there are some systems where the A/C condenser fan & Radiator fan has multiple speeds. Depend on the parameters such as A/C gas temp, A/C gas pressure, Coolant temp and pressure they can cut into a high speed mode ... and some UAE versions even has another 3rd speed to reduce the pressure in A/C system.

[miniace]

Providing straight power supply through ACC select is a widespread following to solve many costly component replacements, if not makes technicians and users verve trouble-free.

The biggest drawback is the prolonged time period to attain the specific range of ideal working temperature. In a tropical country like SL where the average ambient temperature is high and (mainly) use mineral lubrications and fuel of high Sulpher percentage, reaching the mentioned favorable temperature ranges do happen within minutes even with contionus operating cooling fans.

I deny its harmless but its not a prime crime. A faulty thermostat or a relay could spoil the engine to a greater extent.

MINIACE

[Ripper]

Providing straight power supply through ACC select is a widespread following to solve many costly component replacements, if not makes technicians and users verve trouble-free.

The biggest drawback is the prolonged time period to attain the specific range of ideal working temperature. In a tropical country like SL where the average ambient temperature is high and (mainly) use mineral lubrications and fuel of high Sulpher percentage, reaching the mentioned favorable temperature ranges do happen within minutes even with contionus operating cooling fans.

I deny its harmless but its not a prime crime. A faulty thermostat or a relay could spoil the engine to a greater extent.

MINIACE

was thinking on the same lines and never fixed mine but now the fan has got quite loud due to constant running so i'm sure the bugger will die on me pretty soon....

[VVTi]

was thinking on the same lines and never fixed mine but now the fan has got quite loud due to constant running so i'm sure the bugger will die on me pretty soon....

WD40! Solves all your problems.

[Ripper]

WD40! Solves all your problems.

yep...heard that from HellRazor too

but in this case...wd40 will make it go away "temporarily" is my guess

[harshansenadhir]

was thinking on the same lines and never fixed mine but now the fan has got quite loud due to constant running so i'm sure the bugger will die on me pretty soon....

in a more scientific view there are more issues can be triggered due to this, so when the same problem happened in my Lancer CX, this is what I've done to correct it. DIY stuff

1. checked the thermostat with a 5W bulb attached to it and noticed at a certain temperature it lits up. so thermostat sends the signal ( you can further check the thermostat by removing it and place it in a water jug and heat the water using a heater and a temp gauge. then you can notice at which temperature it sends the signal and is up to the manufacturer standard.)

2. Sourced the relay for the fan and checked with the same bulb whether the relay coil supply gets the signal. check Passed.

3. Checked the relay. failed

4. Further short circuited the (+) to the fan and from battery(+) pins of the relay socket (pin no 30 and 87 to be exact). Fan started cut in. check passed.

Replaced the relay and now runs on intervals and temp gauge stays right at the middle.

Drawbacks of running it constantly are not only the wear 'n tear of the fan

1. not reaching the working temperature or taking so long to reach it, fuel efficiency + high wear 'n tare.

2. high draw out of the battery current than usual

3. Point 2. will result in additional power lose of the engine, based on the references it may be as high as 10bhp depending on the amperage of the fan

(of the 406 when both fans engage in high speed mode I clearly feel a load on the engine, and in night there's a slight sudden flicker of the head lights. I don't' think the system can afford to run them continuously)

Edited February 16, 2009 by harshansenadhir

[Ripper]

in a more scientific view there are more issues can be triggered due to this, so when the same problem happened in my Lancer CX, this is what I've done to correct it. DIY stuff

1. checked the thermostat with a 5W bulb attached to it and noticed at a certain temperature it lits up. so thermostat sends the signal ( you can further check the thermostat by removing it and place it in a water jug and heat the water using a heater and a temp gauge. then you can notice at which temperature it sends the signal and is up to the manufacturer standard.)

2. Sourced the relay for the fan and checked with the same bulb whether the relay coil supply gets the signal. check Passed.

3. Checked the relay. failed

4. Further short circuited the (+) to the fan and from battery(+) pins of the relay socket (pin no 30 and 87 to be exact). Fan started cut in. check passed.

Replaced the relay and now runs on intervals and temp gauge stays right at the middle.

Drawbacks of running it constantly are not only the wear 'n tear of the fan

1. not reaching the working temperature or taking so long to reach it, fuel efficiency + high wear 'n tare.

2. high draw out of the battery current than usual

3. Point 2. will result in additional power lose of the engine, based on the references it may be as high as 10bhp depending on the amperage of the fan

(of the 406 when both fans engage in high speed mode I clearly feel a load on the engine, and in night there's a slight sudden flicker of the head lights. I don't' think the system can afford to run them continuously)

hey thanks mate...

looks like i got myself another weekend project

suppose these "thermostats" are easy to source for a toyota corolla

[harshansenadhir]

hey thanks mate...

looks like i got myself another weekend project

suppose these "thermostats" are easy to source for a toyota corolla

pretty easy to my knowledge and cheap too ..

[tharindu6]

will it help me?? i mean " replacing the thermostat"

Cuz even my fan is too loud ...

[harshansenadhir]

will it help me?? i mean " replacing the thermostat"

Cuz even my fan is too loud ...

fan could be too loud to due to improper fixing of the fan or due to worn out motor itself.

[Miyuru Daminda]

Does new EFI car's radiator fan controlled by thermostat switch or car computer

[harshansenadhir]

Does new EFI car's radiator fan controlled by thermostat switch or car computer

some of them directly controlled by the thermostat, but there are much complex ones. However in the systems I know of, it's not the car computer, it's the fan control unit. EFI Fuel calculator, or Engine Control Unit aka car computer mainly looks after the fuel and the ignition part of it. Difference between the fan control unit and ordinary relay is that Fan control unit operate fans depend on multiple parameters such as water temp, external temp, A/C gas temp etc..

Edited February 17, 2009 by harshansenadhir

[Mean Green z28]

When I used to drag race more often, I installed a little wiring harness/switch (got it from a friend who bought it off some vendor) that piggy-backed on the fan wiring harness. What it would do is let me turn on the fans while the car was turned off and cooling down in the pit lanes. It would also let me turn on one or both of the fans even if the temp wasn't high enough to turn the fans on (by the PCM). If the switch was turned off, it'll work just like the factory wanted using the temp switch. Those fan motors are pretty simple/rugged and rarely burn out, so it isn't such a bad thing.