Driver Side Radiator Fan Contantly On
07-05-2015, 06:31 PM
#1
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Driver Side Radiator Fan Contantly On
I am new here to the forums and have looked for this problem but nothing I have done so far has worked.
Here is what happened. I had my friend flush my AC lines, ran vacuum test, and look for any leaks, then replace with new Freon. Car was working great on the drive home with nice cold air. When I got home and turned the car off I noticed that the driver side radiator fan was still running on what sounded to be low speed. I have never noticed this before. I let it set for about 10 minutes and it was still running with car off. I pulled the fuse for that radiator fan (RAD FAN 1) and it turned off and I figured I would check it in the morning. When I came out the next morning and put the fuse back in, that same fan immediately started up again (the car was off and hadn't been ran for over 12 hours). I checked relays by swapping them and even putting a new one that I had laying around in and it still continues to start right away. I then replaced the ETCS since it was cheap and easy to do and still no fix. The radiator fluid level is good and fairly new (changed it about 5 months ago) and i cannot see any other fuses that may be bad. At this point I am stuck and would love any input.
Thanks in advance.
Here is what happened. I had my friend flush my AC lines, ran vacuum test, and look for any leaks, then replace with new Freon. Car was working great on the drive home with nice cold air. When I got home and turned the car off I noticed that the driver side radiator fan was still running on what sounded to be low speed. I have never noticed this before. I let it set for about 10 minutes and it was still running with car off. I pulled the fuse for that radiator fan (RAD FAN 1) and it turned off and I figured I would check it in the morning. When I came out the next morning and put the fuse back in, that same fan immediately started up again (the car was off and hadn't been ran for over 12 hours). I checked relays by swapping them and even putting a new one that I had laying around in and it still continues to start right away. I then replaced the ETCS since it was cheap and easy to do and still no fix. The radiator fluid level is good and fairly new (changed it about 5 months ago) and i cannot see any other fuses that may be bad. At this point I am stuck and would love any input.
Thanks in advance.
07-06-2015, 01:15 PM
#2
This is interesting. RAD FAN 1 relay provides power to both fans for low speed. So for only one fan to be running implies that the contacts inside the relay for the one fan are fused together. But then you said you swapped the relay, so fused contacts don't seem likely.
Unless the wire to the fan that runs has been shorted to a 12 volt wire, the RAD FAN 1 relay would have to be energized. That would mean that both fans would be running. UNLESS - do you know for certain that the other fan is good. Could it be dead?
Then there is the possibility that the fan that is running is running on high speed, not low speed. Each fan has its own relay for high speed. RAD FAN 2 runs the fan on the driver's side at high speed and RAD FAN 3 runs the fan on the passenger side. When the car is turned off, pull out RAD FAN 2 and see what happens, then RAD FAN 3.
You pulled out the fuse labeled RAD FAN 1. This fuse powers both sides of the one radiator cooling fan, the one on the driver's side. The power goes through RAD FAN 1 relay for the low speed side and through RAD FAN 2 relay for the high speed side.
RAD FAN 1, 2 and 3 relays are all the same relay, so you can switch them around any way you want. But pull out RAD FAN 2 relay and see if this stops the fan.
Unless the wire to the fan that runs has been shorted to a 12 volt wire, the RAD FAN 1 relay would have to be energized. That would mean that both fans would be running. UNLESS - do you know for certain that the other fan is good. Could it be dead?
Then there is the possibility that the fan that is running is running on high speed, not low speed. Each fan has its own relay for high speed. RAD FAN 2 runs the fan on the driver's side at high speed and RAD FAN 3 runs the fan on the passenger side. When the car is turned off, pull out RAD FAN 2 and see what happens, then RAD FAN 3.
You pulled out the fuse labeled RAD FAN 1. This fuse powers both sides of the one radiator cooling fan, the one on the driver's side. The power goes through RAD FAN 1 relay for the low speed side and through RAD FAN 2 relay for the high speed side.
RAD FAN 1, 2 and 3 relays are all the same relay, so you can switch them around any way you want. But pull out RAD FAN 2 relay and see if this stops the fan.
07-06-2015, 04:36 PM
#3
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This is interesting. RAD FAN 1 relay provides power to both fans for low speed. So for only one fan to be running implies that the contacts inside the relay for the one fan are fused together. But then you said you swapped the relay, so fused contacts don't seem likely.
Unless the wire to the fan that runs has been shorted to a 12 volt wire, the RAD FAN 1 relay would have to be energized. That would mean that both fans would be running. UNLESS - do you know for certain that the other fan is good. Could it be dead?
Then there is the possibility that the fan that is running is running on high speed, not low speed. Each fan has its own relay for high speed. RAD FAN 2 runs the fan on the driver's side at high speed and RAD FAN 3 runs the fan on the passenger side. When the car is turned off, pull out RAD FAN 2 and see what happens, then RAD FAN 3.
You pulled out the fuse labeled RAD FAN 1. This fuse powers both sides of the one radiator cooling fan, the one on the driver's side. The power goes through RAD FAN 1 relay for the low speed side and through RAD FAN 2 relay for the high speed side.
RAD FAN 1, 2 and 3 relays are all the same relay, so you can switch them around any way you want. But pull out RAD FAN 2 relay and see if this stops the fan.
Unless the wire to the fan that runs has been shorted to a 12 volt wire, the RAD FAN 1 relay would have to be energized. That would mean that both fans would be running. UNLESS - do you know for certain that the other fan is good. Could it be dead?
Then there is the possibility that the fan that is running is running on high speed, not low speed. Each fan has its own relay for high speed. RAD FAN 2 runs the fan on the driver's side at high speed and RAD FAN 3 runs the fan on the passenger side. When the car is turned off, pull out RAD FAN 2 and see what happens, then RAD FAN 3.
You pulled out the fuse labeled RAD FAN 1. This fuse powers both sides of the one radiator cooling fan, the one on the driver's side. The power goes through RAD FAN 1 relay for the low speed side and through RAD FAN 2 relay for the high speed side.
RAD FAN 1, 2 and 3 relays are all the same relay, so you can switch them around any way you want. But pull out RAD FAN 2 relay and see if this stops the fan.
Thanks for the reply. I verified that both fans do work as when i turned on the AC both sides were spinning. Here is what I have tried
1. I removed the relay labeled RAD FAN 2 and left all others in place. When I put the fuse (FAD FAN 1) back into its spot the driver side fan started up again.
2. I removed both RAD FAN 1 and RAD FAN 2 relays. then i replaced the fuse for RAD FAN 1. When I went to connect the relay back into RAD FAN 1 the driver side fan spun up again. Leaving RAD FAN 1 relay empty I tried plugging into RAD FAN 2 and again the fan spun up.
At this point I think it has to be a wiring issue. I just find it odd the this happened after we serviced AC
07-06-2015, 05:08 PM
#4
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Interesting development. I just decided to replace all the original relays and when i put the fuse FAD FAN 1 back into its home the fans DIDN'T spin. Now I am really confused. I will take it for a drive and post back it it happens again.
07-06-2015, 07:54 PM
#5
When the work was done on the a/c, was anything done to the liquid tank or the refrigerant pressure switch? These things are almost right under the relay box and maybe something hit the connections on the bottom of the relay box and bent some of them.
Removing the RAD FAN 1 & 2 relays and then having the fan run when either relay is plugged in, it just too weird for a normal component failure. It has to be a wiring problem and the underside of the relay box is the most logical location. I don't think that replacing the relays really solved the problem except for the fact that wiggling the relays socket around could have "realigned" the pins underneath.
Removing the RAD FAN 1 & 2 relays and then having the fan run when either relay is plugged in, it just too weird for a normal component failure. It has to be a wiring problem and the underside of the relay box is the most logical location. I don't think that replacing the relays really solved the problem except for the fact that wiggling the relays socket around could have "realigned" the pins underneath.
07-08-2015, 09:43 AM
#6
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Thanks for all your help. I am assuming that it was a misaligned pin. No work was done to the tank or switch. the only thing that we did was hook the car up to a bosch A/C service machine.
I thought that everything was fixed and running correctly but now I have a question regarding the passenger side fan. First for clarification is the driver side fan for the A/C and the passenger for the engine coolant? I know that the condenser and radiator are parallel so it would seem that they affect both the same. The only reason I ask this is because when I start the car with no A/C on and the car is cooled down, no fans are running, which is fine. When I turn on the A/C the driver side fan comes on and the passenger stays off (same if the A/C is blowing low or max speed). I have not had any problems with the car overheating but I have stopped multiple times while driving and looked to see if the passenger side fan was on and it has not been. Is this die to the fact that the engine hasn't reached high enough temperature for the passenger fan to kick on? I will say that the driving has been in town and not for more than about 30 minutes.
I thought that everything was fixed and running correctly but now I have a question regarding the passenger side fan. First for clarification is the driver side fan for the A/C and the passenger for the engine coolant? I know that the condenser and radiator are parallel so it would seem that they affect both the same. The only reason I ask this is because when I start the car with no A/C on and the car is cooled down, no fans are running, which is fine. When I turn on the A/C the driver side fan comes on and the passenger stays off (same if the A/C is blowing low or max speed). I have not had any problems with the car overheating but I have stopped multiple times while driving and looked to see if the passenger side fan was on and it has not been. Is this die to the fact that the engine hasn't reached high enough temperature for the passenger fan to kick on? I will say that the driving has been in town and not for more than about 30 minutes.
Last edited by Brakendone; 07-08-2015 at 09:45 AM.
07-09-2015, 10:45 AM
#8
You have a dead passenger side fan. Whenever a fan is supposed to run, both fans run whether you are talking low speed or high speed. The system is not designed to run only one fan.
When starting the car with a cold engine and no a/c on, the fans will not run. When the engine coolant reaches 203º F, the the fans will run at low speed. When the fans cool the engine coolant to below 190º F, then the fans will turn off. If the coolant temperature gets up the 212º F, then the fans will run at high speed.
When you turn on the a/c, the fans will run at low speed. A/c requires the cooling fans for the condenser coil that is mounted in front of the radiator. The a/c system needs this and the temperature of the engine plays absolutely no part in this. If needed by the engine (coolant temperature at 212º F), the fans will run at high speed.
As I said above, you have a dead fan on the passenger side. Check the RAD FAN 2 fuse and see if it is blown. If it is, you can try another fuse, but I think it will probably blow instantly. A check you can do to the fan motor is the see if you can wiggle the fan blade. There should be no wiggle. Not even a little. You can compare it to the working fan, which I'm sure is getting a good workout now a days.
You can replace individual fans if you want. A lot of people get the complete fan assembly that includes both fans and the plastic shroud they mount in. Which ever way you want to do it.
When starting the car with a cold engine and no a/c on, the fans will not run. When the engine coolant reaches 203º F, the the fans will run at low speed. When the fans cool the engine coolant to below 190º F, then the fans will turn off. If the coolant temperature gets up the 212º F, then the fans will run at high speed.
When you turn on the a/c, the fans will run at low speed. A/c requires the cooling fans for the condenser coil that is mounted in front of the radiator. The a/c system needs this and the temperature of the engine plays absolutely no part in this. If needed by the engine (coolant temperature at 212º F), the fans will run at high speed.
As I said above, you have a dead fan on the passenger side. Check the RAD FAN 2 fuse and see if it is blown. If it is, you can try another fuse, but I think it will probably blow instantly. A check you can do to the fan motor is the see if you can wiggle the fan blade. There should be no wiggle. Not even a little. You can compare it to the working fan, which I'm sure is getting a good workout now a days.
You can replace individual fans if you want. A lot of people get the complete fan assembly that includes both fans and the plastic shroud they mount in. Which ever way you want to do it.
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