Need HELP ASAP! OverHeating!

[BlkWidow]

I running short on time to fix my problem, I just replaced my radiator that started leaking today. When I run the car any length of time my fan does not come on at all(it should cycle on and off to cool the radiator like I have seen it do), if I turn my blower motor on in the car the the fan on the radiator starts cycling the normal it does. But the moment I turn the fan off in the car it goes back to not working again, so I think I have a bad sensor. Have I got the right answer, if anyone can point me to the part# and location on the car would really help. wilson

P.S. I have to go to my son's football game, anybody think it would be a problem to use it this way with the fan?

[Metallic36]

Thermostat, by chance? http://www.fixya.com/cars/t1144411-2001_mazda_protege_cooling_fan_or

My link wouldn't work, but I found a fan relay on onlinemazdaparts.com for $14.43

[BlkWidow]

Thermostat, by chance?
should have also stated that it's also new.

[slavrenz]

I running short on time to fix my problem, I just replaced my radiator that started leaking today. When I run the car any length of time my fan does not come on at all(it should cycle on and off to cool the radiator like I have seen it do), if I turn my blower motor on in the car the the fan on the radiator starts cycling the normal it does. But the moment I turn the fan off in the car it goes back to not working again, so I think I have a bad sensor. Have I got the right answer, if anyone can point me to the part# and location on the car would really help. wilson

P.S. I have to go to my son's football game, anybody think it would be a problem to use it this way with the fan?

Did this only start happening after you replaced the radiator? I'm thinking you may have a bad coolant temp sensor. Also, just turn your fan controls on in the car so you don't overheat.

[BlkWidow]

Did this only start happening after you replaced the radiator? I'm thinking you may have a bad coolant temp sensor. Also, just turn your fan controls on in the car so you don't overheat.No, I think it happen before and that's what killed the radiator.

[Thefriar]

What does your temp guage read on the dash right when you first hop in in the morning? Cause the Coolant temp sensor is the PCM input that should be cycling your fan on and off.



the fan will always come on with a/c because you are putting extra load on the engine by running the compressor, and the fan helps airflow across the condensor for better a/c efficiency

[slavrenz]

No, I think it happen before and that's what killed the radiator.

What is your temp needle at when you are driving around? If it never reaches the red, you're not overheating. More likely corrosion in your cooling system plugged up your radiator, but I still think you might have a bad coolant temp sensor.

[slavrenz]

What does your temp guage read on the dash right when you first hop in in the morning? Cause the Coolant temp sensor is the PCM input that should be cycling your fan on and off.



the fan will always come on with a/c because you are putting extra load on the engine by running the compressor, and the fan helps airflow across the condensor for better a/c efficiency

To the OP - please clarify. Does the fan on the driver's side of your engine compartment ever engage? Or is it just the A/C fan (on the passenger side) that turns on. If the regular fan never turns on, I'd be checking for a blown fuse, or a burnt out fan motor.

[boostdprotegelx]

did you put the t stat in backwards?

[BlkWidow]

My driver's side fan never turns on if I leave the inside blower off, if I turn the inside blower on then the fan will turn on and off to cool the radiator down. I did not put the stat in backwards, dash temp gauage shows reading when the car is hot.

[BlkWidow]

The coolant sensor is not tied into turning the fan on, is their a timed relay for the fan. I need to know what turns the fan on the driver's side on, I have replaced a radiator, thermostat is new(installed the right way and working) and know that the coolant sensor is only for dispaly. If I turn the interior blower to low my driver's side fan will cycle on and off with no problems, I turn the interior blower to off the fan will never cycle on. I have check all fuse, the fan does work so what am I missing or need to check?

[DeanSweet]

When you replaced the radiator? is there an additional plug on the side of the radiator that's not plugged in? I had the same problem after replacing the radiator in my isuzu and it was the simple fact I didn't plug that sensor in? could be worth a look?

[BlkWidow]

When you replaced the radiator? is there an additional plug on the side of the radiator that's not plugged in? I had the same problem after replacing the radiator in my isuzu and it was the simple fact I didn't plug that sensor in? could be worth a look?Their are no extra or missing plugs, it's relay or short in the HVAC controls.

[slavrenz]

The coolant sensor is not tied into turning the fan on, is their a timed relay for the fan. I need to know what turns the fan on the driver's side on, I have replaced a radiator, thermostat is new(installed the right way and working) and know that the coolant sensor is only for dispaly. If I turn the interior blower to low my driver's side fan will cycle on and off with no problems, I turn the interior blower to off the fan will never cycle on. I have check all fuse, the fan does work so what am I missing or need to check?

This is incorrect. The engine coolant temperature sensor is an integral part of your engine management system - it affects everything from your a/f ratio to the display on your dashboard. If you've got a wacky temp sensor that's telling your car that the coolant is cold, it's not going to turn the fan on unless forced to (i.e., by you turning on the blower).

[BlkWidow]

The sensor is new and its still doing the same thing

[BlkWidow]

anyone know?

[shane02pro5]

Try running direct power and ground to the fan to see if it comes on at all. Should only come on normally above 205. I have had a faulty thermostat before straight out of the box. Also if the entire system wasn't flushed there may be some new blockage...doesn't take much at all. A flush will also clean the sensor if its just some build up.

[BlkWidow]

Try running direct power and ground to the fan to see if it comes on at all. Should only come on normally above 205. I have had a faulty thermostat before straight out of the box. Also if the entire system wasn't flushed there may be some new blockage...doesn't take much at all. A flush will also clean the sensor if its just some build up.
I have done all that, and it still will not cycle right.

[shane02pro5]

cel?

[BlkWidow]

cel?
Their is no cel, I took the car for a nice long drive. Turns out that the car is running good, could it be the reflashed msp ecu has a different fan cycle then my MP5.

[Thefriar]

The coolant sensor is not tied into turning the fan on, is their a timed relay for the fan. I need to know what turns the fan on the driver's side on, I have replaced a radiator, thermostat is new(installed the right way and working) and know that the coolant sensor is only for dispaly. If I turn the interior blower to low my driver's side fan will cycle on and off with no problems, I turn the interior blower to off the fan will never cycle on. I have check all fuse, the fan does work so what am I missing or need to check?


oh yes it is but thats all done inside the pcm man. You wont see that in a wiring diag.
to tell you but its all done with pcm logic when the pcm sees a certain temp it kicks the fan on to cool it down, then when its cool enough the fan kicks off


again what i ask is what does the dash guage read? (with key on engine off after cold soak)

[Thefriar]

The coolant sensor is not tied into turning the fan on, is their a timed relay for the fan. I need to know what turns the fan on the driver's side on, I have replaced a radiator, thermostat is new(installed the right way and working) and know that the coolant sensor is only for dispaly. If I turn the interior blower to low my driver's side fan will cycle on and off with no problems, I turn the interior blower to off the fan will never cycle on. I have check all fuse, the fan does work so what am I missing or need to check?



it is def not only for display my man


but, your fan turns on with just the blower in vent or heat?
That fan should not kick on until you actually turn the a/c on not just the blower.

[Thefriar]

I have done all that, and it still will not cycle right.

wont cycle right but does it at least turn on??????

[Thefriar]

The sensor is new and its still doing the same thing


yes, its new, but who's to say that you dont have a circuitry problem?????????

have you checked the circuits integrity??? if not i'd recommend doing a volt drop on the coolant sensors circuits power and return(also known as pcm ground)
any more than .5V and the manufacturer see's that as high resistance and thats probably gonna cause poor readings too

[Thefriar]

if you want some help with how this system actually operates, (and some insight on the pcm's role in all of this) give me a jingle @ 505-412-3508

[br289165]

Maybe I missed something in these posts but I don't recall seeing anybody mentioning to look at the most obvious thing first, before ordering sensors, relays and changing thermostats, whatever. Are you certain the sensor is only for display? if you have air in the system , the coolant wont get hot enough at the sensor, just in the block and the fan wont come on . You say it works with the "blower" on, do you mean on the AC and defrost settings the fans work? Did you bleed the system fully? Usually both fans should work with the AC button in.




The coolant sensor is not tied into turning the fan on, is their a timed relay for the fan. I need to know what turns the fan on the driver's side on, I have replaced a radiator, thermostat is new(installed the right way and working) and know that the coolant sensor is only for dispaly. If I turn the interior blower to low my driver's side fan will cycle on and off with no problems, I turn the interior blower to off the fan will never cycle on. I have check all fuse, the fan does work so what am I missing or need to check?

[Thefriar]

Maybe I missed something in these posts but I don't recall seeing anybody mentioning to look at the most obvious thing first, before ordering sensors, relays and changing thermostats, whatever. Are you certain the sensor is only for display? if you have air in the system , the coolant wont get hot enough at the sensor, just in the block and the fan wont come on . You say it works with the "blower" on, do you mean on the AC and defrost settings the fans work? Did you bleed the system fully? Usually both fans should work with the AC button in.


excellent call on the air pocket!!!!
also if there is an air pocket under the thermostat, it WILL NOT open

but the second fan should not kick on until you turn on A/C (and that means actually engaging the A/C compressor by hitting the a/c button, not just the blower motor on vent or defrost)

[br289165]

I believe the compressor engages on the defrost setting when u turn the blower knob even without pressing the AC button..


excellent call on the air pocket!!!!
also if there is an air pocket under the thermostat, it WILL NOT open

but the second fan should not kick on until you turn on A/C (and that means actually engaging the A/C compressor by hitting the a/c button, not just the blower motor on vent or defrost)