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Can someone please help, im not that great at electrical problems. I have an 04 TL, 120k mile, auto. i just noticed that my radiator fan will not run unless the ac is running, however the car temp does not go above the right edge of the 2 bottom squiggly lines on the temp Guage inside the car no matter how long i drive or let it sit idle but it seems like the engine is really hot when i pop the hood. In other words it doesn't even reach mid way on the gauge. I have tried switching the relays around in the box under the hood but that did not help. I felt the houses coming from the radiator and the top one is really hot but the bottom one was no where near hot, maybe a bad thermostat? But would a bad thermostat keep the fan from running? The fans do not run at all when i cut the car of like some peoples cars do. Any help would greatly be appreciated.
If your heater works, the radiator is full of fluid, the fans run with the A/C, the hoses get hot, and the temp gauge is normal...then more than likely things are just fine. Engines get hot. Engine bays get hot.
If you are driving the car, good chance the fans will never come on. With forward movement comes fresh air through the radiator. Let the car idle for 20-30 minutes...the fans will kick on.....or you'll overheat.
If your heater works, the radiator is full of fluid, the fans run with the A/C, the hoses get hot, and the temp gauge is normal...then more than likely things are just fine. Engines get hot. Engine bays get hot.
If you are driving the car, good chance the fans will never come on. With forward movement comes fresh air through the radiator. Let the car idle for 20-30 minutes...the fans will kick on.....or you'll overheat.
I'll try the idle in the driveway and see what happens. I live in Va and it's 94 degrees outside right now, not that that's screaming bloody hot but it's not 30 degrees here. I remember last year always hearing the fans (when the a.c. was running) cycle on and off. Its not doing tjat this time.
BTY- the service manual says the radiator fan is on the drivers side, but I've seen quite a few other post saying it's on the passenger side. Do you know which is which?
In my previous car - accord, i had the same sympthoms. In the summer, in traffic jams, when engine temperature was raising i had to turn on the ac to cool it down. The thermoswitch was dead. It was not expensive and easy to DIY.
In my previous car - accord, i had the same sympthoms. In the summer, in traffic jams, when engine temperature was raising i had to turn on the ac to cool it down. The thermoswitch was dead. It was not expensive and easy to DIY.
Thanks for the help mariusz439, if I can get the part from the local O'Reilly's today I'll give it a shot. Can't hurt anything.
BTY- the service manual says the radiator fan is on the drivers side, but I've seen quite a few other post saying it's on the passenger side. Do you know which is which?
I have no idea which is which...I have never actually looked at my fans. I look at my engine bay about twice a year...to clean it, refill washer fluid, and to check the battery.
Ok, I know this might be a DUMB question but I haven't found anything on it that is definitive. The switch I'm referring to is located near the thermostat. It has a wire harness (2 wires) connected to it. The question is does this have anything to do with the radiator fan cutting on? Everything I read says it measures water temp, sends that info to the computer along with the air flow, gas and that is used to adjust the idle such as on colds days. If it doesn't, where is the switch that turns the radiator fan on?
Hmm, so youre saying there's a fan that's turning on when you turn on the ac, but isn't correlated to engine temp. Mystery for the ages
park your car, let it sit there for a couple minutes and your cooling fan should kick on. I don't recall ever hearing my fan after I shut the car off.
Also, get a skunk 2 radiator cap. keeps the engine a bit cooler. Can't hurt.
Hmm, so youre saying there's a fan that's turning on when you turn on the ac, but isn't correlated to engine temp. Mystery for the ages
park your car, let it sit there for a couple minutes and your cooling fan should kick on. I don't recall ever hearing my fan after I shut the car off.
Also, get a skunk 2 radiator cap. keeps the engine a bit cooler. Can't hurt.
All I know is neither fan cuts on when the car is showing midway on the temp gage inside the car, even if i let it sit and idle or tev the engine. But even if the engine is cold and I cut the a.c. on, both fans cut on. I've never heard my fan run after I cut my car is off, that's what some other owners have said in their posts that I've read trying to figure this out. Thanks for the reply.
Passenger side fan is the AC fan, driver side is radiator. I'd let the car idle for a good 45minutes before I'd say your radiator fan isn't working. I remember when I thought my radiator fan was working as well, but I had to let the car warm up to temp before it came on; took a good 45min.
Ok, so I ran the car at 65mph for about 25 min. Temp gage showing midrange, I had the keys in the ignition but nothing on. I disconnected the thermo switch and the radiator fan came on full speed. When I started the car, the ac fan cut on and the radiator fan kept running. I reconnected the temp switch and cut the car off. The radiator fan is still running. Any ideas on this?
PS: Thanks to all that have tried to help me on this.
Yeah, the engine coolant temp sensor is mounted in the water passage in back of the thermostat. It is definitely involved in the radiator fans. These images are from the 2004 FSM. Not sure what year yours is.
Here's the schematic. In extremely high coolant temperature conditions(Above 206°F (97°C)), the ECM/PCM provides ground to the coils of the A/C condenser fan relay,the radiator fan relay, and the fan control relay,energizing them. Battery voltage is supplied to the A/C condenser fan motor and radiator fan motor through their respective energized relays, which activates the motors at high speed.
Thank you Adobeman. I do have an 04 with 115k or so mikes in it. For some reason recently, the radiator fan quit working. I know this because I've owned the car for 7 or so years and know how it used to work. When I cut the a.c. on both fans cut in at high speed. When I cut the a.c. off, both fans cut off. I tried the relays and they are good, I even replaced the fan control relay that is in a separate box on the side of the fuse/relay box under the hood and that did not fix it. Today, I disconnected the wire harness to the temp sensor and the radiator fan cut on at high speed, and the keys were NOT in the ignition. I've never heard the fan run with the car off before. Any ideas?
Thank you Adobeman. I do have an 04 with 115k or so mikes in it. For some reason recently, the radiator fan quit working. I know this because I've owned the car for 7 or so years and know how it used to work. When I cut the a.c. on both fans cut in at high speed. When I cut the a.c. off, both fans cut off. I tried the relays and they are good, I even replaced the fan control relay that is in a separate box on the side of the fuse/relay box under the hood and that did not fix it. Today, I disconnected the wire harness to the temp sensor and the radiator fan cut on at high speed, and the keys were NOT in the ignition. I've never heard the fan run with the car off before. Any ideas?
its could a fail safe mechanism when the temp sensor is disconnected; the fan cuts on bc it cannot gauge a temperature reading so it turns on to prevent overheating. You got a manual?
Well at least you know for sure its not the fan motor or the relays.
its could a fail safe mechanism when the temp sensor is disconnected; the fan cuts on bc it cannot gauge a temperature reading so it turns on to prevent overheating. You got a manual?
Well at least you know for sure its not the fan motor or the relays.
Hi Duronn, not sure if your talking about the transmission or an instruction manual, not trying to be funny, i need all the help I can get amd appreciate your input. I have an automatic and i downloaded the service manual. The SM does not talk about the fan running with the harness unplugged and the car off. You just might be right about failsafe though and it's a cheap and easy replacement so I'll try it and let everyone know if it fixed it. Thanks for the help.
I meant "service manual." What does the service manual say about testing the engine coolant temperature sensor? There has to be a way to test the sensor if it's malfunctioning.
Passenger side fan is the AC fan, driver side is radiator.
To note, on my '05, both fans appear to be "radiator" fans. This thread perked my interest in checking a few things out, so I replaced my radiator cap and coolant tank cap just in case....and let the car idle in the garage. From inside the car and even in the garage, I cannot hear my fans at all. Only if I had the hood open and was looking could I tell my fans were on. Both fans on mine cycle on and off together. I had driven to the dealership to pick up coolant and power steering fluid and then back home which is about 9 miles round trip, then it sat idling in the garage for about 6-7 minutes before I finally noticed the fans on. They could have come on sooner since I couldn't actually hear them and may not have been looking when they cycled.
To note, on my '05, both fans appear to be "radiator" fans. This thread perked my interest in checking a few things out, so I replaced my radiator cap and coolant tank cap just in case....and let the car idle in the garage. From inside the car and even in the garage, I cannot hear my fans at all. Only if I had the hood open and was looking could I tell my fans were on. Both fans on mine cycle on and off together. I had driven to the dealership to pick up coolant and power steering fluid and then back home which is about 9 miles round trip, then it sat idling in the garage for about 6-7 minutes before I finally noticed the fans on. They could have come on sooner since I couldn't actually hear them and may not have been looking when they cycled.
Hey Jackass, did you by chance have your a.c. on? From all my research and the help of people like you from Azine, the passenger fan is the ac fan and should only come on when running the ac or if the car is running really hot.
BYW: I believe I have a bad temp sensor and a new OEM one will arrive today and I'm going to change it out. Will update after the install to let everyone know if that fixed my issue.
Hey Jackass, did you by chance have your a.c. on? From all my research and the help of people like you from Azine, the passenger fan is the ac fan and should only come on when running the ac or if the car is running really hot.
Negative on the A/C being on. It was in the 50s here yesterday morning so no need for heat or A/C.
Hey Jackass, did you by chance have your a.c. on? From all my research and the help of people like you from Azine, the passenger fan is the ac fan and should only come on when running the ac or if the car is running really hot.
BYW: I believe I have a bad temp sensor and a new OEM one will arrive today and I'm going to change it out. Will update after the install to let everyone know if that fixed my issue.
Update: After install of the new temp sensor and it's a no go. Same problem occurring. Maybe I'll try in the electrical postings, it's got to be something electrical unless in the unlikely event I got a bad new sensor, which I doubt. Thanks for all your help Aziners.
Hi Aziners, I have an 04 Tl with approx. 115k miles on it, automatic. The problem I'm having is that the radiator fan is not cutting on when the cars inside temp gage is reading in the middle. Ive let it sit and idle, rev'd the engine etc. And it doesn't cut on. I've checked the relay, replaced the temp sensor near the thermostat under the hood and nada, nothing. However the fan does run when I turn the a.c. on so I know the motor is good. Any ideas would be greatly appreciated.
I meant "service manual." What does the service manual say about testing the engine coolant temperature sensor? There has to be a way to test the sensor if it's malfunctioning.
I just went ahead and replaced the temp switch, but it's still doing the same thing. It didn't fix the problem.
Yeah, the engine coolant temp sensor is mounted in the water passage in back of the thermostat. It is definitely involved in the radiator fans. These images are from the 2004 FSM. Not sure what year yours is.
Here's the schematic. In extremely high coolant temperature conditions(Above 206°F (97°C)), the ECM/PCM provides ground to the coils of the A/C condenser fan relay,the radiator fan relay, and the fan control relay,energizing them. Battery voltage is supplied to the A/C condenser fan motor and radiator fan motor through their respective energized relays, which activates the motors at high speed.
Adobeman, can you tell me where the ECM/PCM is located, I replaced the temp sensor and it's still doing the same thing, radiator fan is not cutting on unless I cut the a.c. on. Thank you.
You have started at least three threads now for the same issue. As you chase down issues, it makes it waaaaay easier for others to help if all of the history is in one place. Something is broken, you need it fixed...that can easily stay in the Problems and Fixes forum.
And yes...I am a Jackass. Welcome to the forums. If I make you feel unwelcomed...you will be in for a treat eventually. I may be a smartass...but rarely am I actually rude and unwelcoming. There is a lot of help on the forums...just be patient and helpful and others will eventually be long to provide further guidance.
Jackass has a point. It's terribly difficult to follow multiple threads on a single problem. As such I'm merging them all into one so everyone has all the info in one place to better assist you.
Jackass has a point. It's terribly difficult to follow multiple threads on a single problem. As such I'm merging them all into one so everyone has all the info in one place to better assist you.
Well like he said, being a smartass isn't a good way to be towards fairly new people. Unless of course you don't want many people visiting. I appreciate you compiling them into one post. Just for my info in the future, if I have what I believe is a mechanical problem but could also very well be an electrical problem, what would be the best thread to put it it? Thank you thoiboi.
Last edited by fulla; 05-04-2017 at 07:49 PM.
Reason: Editorial
Well like he said, being a smartass isn't a good way to be towards fairly new people. Unless of course you don't want many people visiting. I appreciate you compiling them into one post. Just for my info in the future, if I have what I believe is a mechanical problem but could also very well be an electrical problem, what would be the best thread to put it it? Thank you thoiboi.
Here's my take on it - When you are new anywhere you will form first impressions of others. Before being too quick to judge a bad initial experience with someone take a look at past actions. Here that's simple to do. Take look at their profile and go the the part where you can see their past posts. Look at some and only then form your opinion. Is that a perfect world? Nope. Will it help you calibrate your opinions and expectations? Yes. It's all part of learning to fish instead of being given a fish. We hand out LOTS OF FISH willingly to those that we can tell are attempting to learn to fish. I think you are trying.
With respect to where to post - To me you are stating you have a problem with a fan. Whether its root is electrical or mechanical or both you still have a problem with a fan. So to me that's one single issue in "Problems & Fixes." Let the discussion go where it may with respect to sensors, relays, wires and fans. No need to break those out into separate threads. A "broken radio" example might end up in either Bluetooth, Electronics & Navigation OR Problems and Fixes but as long as it's a single post don't sweat it. It will get seen, people will help and mods will move it if they think it needs to be.
Here's my take on it - When you are new anywhere you will form first impressions of others. Before being too quick to judge a bad initial experience with someone take a look at past actions. Here that's simple to do. Take look at their profile and go the the part where you can see their past posts. Look at some and only then form your opinion. Is that a perfect world? Nope. Will it help you calibrate your opinions and expectations? Yes. It's all part of learning to fish instead of being given a fish. We hand out LOTS OF FISH willingly to those that we can tell are attempting to learn to fish. I think you are trying.
With respect to where to post - To me you are stating you have a problem with a fan. Whether its root is electrical or mechanical or both you still have a problem with a fan. So to me that's one single issue in "Problems & Fixes." Let the discussion go where it may with respect to sensors, relays, wires and fans. No need to break those out into separate threads. A "broken radio" example might end up in either Bluetooth, Electronics & Navigation OR Problems and Fixes but as long as it's a single post don't sweat it. It will get seen, people will help and mods will move it if they think it needs to be.
+2
A problem is a problem is a problem. And don't sweat too much about where you put it. The mods will rearrange as needed anyway ; this subsection is the best place for your issue though.
I decided to change the thermostat, any ideas wht this rubbery type thing is on the engine side of the thermostat? My upper rad hose was hot after driving and my bottom hose is cold, thats why i changed the thermostat.
And this is inside the thermostat housing on the engine, any idea what that blackish tho g is in the Hope? Is it supposed to be there? Thanks for everyone's help.
I "think" that is the gasket that is supposed to be sitting on the top lip of the button that is sticking down???
So in theory your thermostat was stuck open? So your engine temps never quite got up to full temp maybe?
damn spell check ain't working well in my above post. Sorry about that. I wish that was the case. I replaced my thermo and it's doing the same thing. Fan doesn't cut on, temp gage is in the middle and the top rad hose is hot and the bottom one is cool. Do you know which hose supplies the engine with cool water?
PS: I JUST checked the original thermo with the rubbery stuff on it and it opened fine.
I also didn't see any water movement in the radiator as if the water pump wasn't pushing water, but that could be due to the thermo not opening. My car NEVER acted like this before. I guess at this point I'm going to drive it till something happens.
You have started at least three threads now for the same issue. As you chase down issues, it makes it waaaaay easier for others to help if all of the history is in one place. Something is broken, you need it fixed...that can easily stay in the Problems and Fixes forum.
And yes...I am a Jackass. Welcome to the forums. If I make you feel unwelcomed...you will be in for a treat eventually. I may be a smartass...but rarely am I actually rude and unwelcoming. There is a lot of help on the forums...just be patient and helpful and others will eventually be long to provide further guidance.
Hey Jackass, I just wanted to publicly apologize for being rude. That's really not who or how i am and if I offended you I'm sorry. My car issues have me frazzled right now and I really do appreciate all the help I can get. Thanks and sorry again.
And thanks also to theoboi for piling all my post together.
I "think" that is the gasket that is supposed to be sitting on the top lip of the button that is sticking down???
yeah, something about it doesn't look all that alarming. The edges on it seem to be "man made" rather than random garbage. But there's really no easy way to tell without happening to find other pictures (unlikely) or someone else who definitely knows joining in. Looking at the parts diagram doesn't help either since that part of the water passage has no real exploded view.
Originally Posted by Jackass
So in theory your thermostat was stuck open? So your engine temps never quite got up to full temp maybe?
Could be. T-stat needs to be changed either way. Bat car should still come up to temp eventually on a hot day.
And there's that green/yellow coolant.... Yeah I know there are silicate free brands but the OE blue stuff is just so easy and a "known good" item. When you re-fill you may want to fully drain and use Honda/Acura premix. Since you're doing all this work....
EDIT - Wow lot's happened while I was typing. Never mind most of it I guess
Last edited by Adobeman; 05-05-2017 at 03:18 PM.
Reason: Became obsolete
that arbitrary piece of melted rubber definitely shouldn't be there.. you should get a new thermostat Maybe a piece of gasket somewhere in the cooling system warped/melted/ and got stuck in there causing the thermostat to stay open.
And you're very welcome Sometimes our emotions get the best of us! :gheyhug:
that arbitrary piece of melted rubber definitely shouldn't be there.. you should get a new thermostat Maybe a piece of gasket somewhere in the cooling system warped/melted/ and got stuck in there causing the thermostat to stay open.
And you're very welcome Sometimes our emotions get the best of us! :gheyhug:
Lucky for me I guess i have a guy that works for me and he came by today to take a look and worse news, he believes the water pump is bad due to not seeing any water movement in the radiator and the bottom hose is not getting hot at all. He used to be the service manager at a local Acura dealer so I trust him. He's also a great employee. He works on cars on the side and said he would do the labor for the water pump, timing belt, tensioner pulley and motor mount for 400.00. What do you all think?
04-29-2017, 11:56 AM
; this subsection is the best place for your issue though.
