Radiator Fans Draining Battery
11-27-2014, 05:50 PM
#1
Radiator Fans Draining Battery
Has anyone experienced this issue where both radiator fans will turn ON when the car is shut off and keep running until the battery is completely drained. The fans immediately switch off when the car is turned on and functional normally under driving conditions or when A/C is turned on. This just started happening all of a sudden.
11-28-2014, 04:15 AM
#3
^^^ I agree. RAD FAN 1 relay is the most logical cause. You can swap it with any same colored relay.
But don't use the other blue relay that is by the RAD FAN 1 relay. Go to the other box and use the HORN 2 or 3 relay. You don't want to risk putting a bad relay in the EGI position.
But don't use the other blue relay that is by the RAD FAN 1 relay. Go to the other box and use the HORN 2 or 3 relay. You don't want to risk putting a bad relay in the EGI position.
11-28-2014, 04:47 PM
#5
Just tried swapping RADFAN1 relay with another however it didn't stop the fans from coming on when the car is off. I tried swapping out RADFAN 2 and 3 relays too with no luck. I noticed that the fan's will stop only when both relays 2 and 3 are pulled out. When only relay 2 is pulled out I can hear the clicking in the relays to try to engage the fans but they don't actually come on.
This did start happening a couple days after I took the car into a car wash so I was also thinking there may be a relay shorted somewhere but I don't see any signs of water in any of the systems.
This did start happening a couple days after I took the car into a car wash so I was also thinking there may be a relay shorted somewhere but I don't see any signs of water in any of the systems.
11-28-2014, 05:54 PM
#6
Well well well... the RAD FAN 2 & 3 relays are for the high speed half of the fan motors.
RAD FAN 1 relay when energized, sends power to both radiator fans so they will run at low speed. For high speed, each fan motor has its own relay. These circuits for high speed are independent from each other, so I am somewhat surprised by what you discovered.
In normal operation, the ECU causes the relays to energize, pin 14 for low speed and pin 13 for high speed. The ignition switch sends 12 volts to the relay energizing coils when the key is in the ON position and the ECU turns them on as needed. When the ignition switch is turned off, there should not be 12 volts for the fan relays.
Since I don't know exactly what the cause of the problem could be, you will have to do some trial and error troubleshooting. Here are some things to try. Do these one at a time when the car is off and the fans are running, in any order you want.
1 - Remove fuse # 17 from the dashboard fuse panel. This is a 10 amp fuse in the middle column, 6th one from the bottom. The label calls it ENGINE CONTROL.
2 - Remove fuse D from the fuse block by the battery. The cover labels it RAD FAN 1.
3 - Remove fuse E from the fuse block by the battery. The cover labels it RAD FAN 2.
4 - Remove the connector from the a/c triple pressure switch. This is mounted next to the radiator on the drivers side, on top of a round silver tank.
5 - Unplug the fan motors one at a time. The plugs are on the plastic shroud that surrounds the fan blades.
If one of the fuses in tests makes the fans stop, you can use that as a way of shutting off the fans until we get this figured out. Of course you will have to put the fuse back in when you drive the car.
- - - - - - - - - - - - - - - - - - - -
RAD FAN 1 relay when energized, sends power to both radiator fans so they will run at low speed. For high speed, each fan motor has its own relay. These circuits for high speed are independent from each other, so I am somewhat surprised by what you discovered.
In normal operation, the ECU causes the relays to energize, pin 14 for low speed and pin 13 for high speed. The ignition switch sends 12 volts to the relay energizing coils when the key is in the ON position and the ECU turns them on as needed. When the ignition switch is turned off, there should not be 12 volts for the fan relays.
Since I don't know exactly what the cause of the problem could be, you will have to do some trial and error troubleshooting. Here are some things to try. Do these one at a time when the car is off and the fans are running, in any order you want.
1 - Remove fuse # 17 from the dashboard fuse panel. This is a 10 amp fuse in the middle column, 6th one from the bottom. The label calls it ENGINE CONTROL.
2 - Remove fuse D from the fuse block by the battery. The cover labels it RAD FAN 1.
3 - Remove fuse E from the fuse block by the battery. The cover labels it RAD FAN 2.
4 - Remove the connector from the a/c triple pressure switch. This is mounted next to the radiator on the drivers side, on top of a round silver tank.
5 - Unplug the fan motors one at a time. The plugs are on the plastic shroud that surrounds the fan blades.
If one of the fuses in tests makes the fans stop, you can use that as a way of shutting off the fans until we get this figured out. Of course you will have to put the fuse back in when you drive the car.
- - - - - - - - - - - - - - - - - - - -
Last edited by DennisMik; 11-30-2014 at 02:05 PM. Reason: Had fuse labels wrong in steps 2 & 3. Incorrectly called them C & D.
11-29-2014, 10:07 PM
#7
Thanks for that explanation - I had no idea how the fans are wired and the description helps understand how things are working in the system. I've resorted to option 3 - removing fuse D for RAD FAN 2 to stop the fans instead of disconnecting the battery each time. The fans stop immediately when the fuse is removed. Options 1, 2, and 4 did not stop the fans.
I drove the car quite a bit today and there are no CEL's of any kind. I will try resetting the ECU tomorrow to see if this helps to resolve the issue.
I drove the car quite a bit today and there are no CEL's of any kind. I will try resetting the ECU tomorrow to see if this helps to resolve the issue.
11-30-2014, 02:46 PM
#9
The fuse that you removed (fuse D in step 3) provides the power for the high speed half of the fan motors. So this definitely confirms that the problem is in the high speed circuit.
As far as driving with that fuse pulled out, you should be OK. The outside temps are lower and you probably are not using the a/c. Just keep an eye on your temperature gauge.
But as for what is causing this problem, I don't know. When the car is turned off, the relays should not be able to energize because the 12 volts for this comes from the ignition switch in the ON position. Secondly the 12 volts then has to go through fuse 17 (step 1 above). Removing this fuse had no effect.
So my first assumption is that the relays could not be energized. Yet the 12 volts from fuse E (step 3 above) is getting to the fan motors, which says the relays have energized and closed the connections inside the relay. One could assume that the connection contacts in the relay have fused together to allow this. But this can't be the case because when you start the car, the fans stop.
I am hard pressed to visualize how a single component could cause this. I can visualize a senario involving a bad relay combined with a bad fan motor, but that theory has serious flaws.
Do the fans seem to be running at full speed? And both and both at the same speed? I would really like you to do my step 5 above, unplug one fan at a time.
Another thing I would like you to try requires the car to have an automatic transmission. If it does, unplug the relay labeled ASCD that is in the same box with the RAD FAN relays. Then, unplug the RAD FAN 2 relay and plug in the ASCD relay. Then do this with RAD FAN 3.
Do you have a voltmeter and can do basic measuring? I am thinking there is some wiring problem and we will need to use a voltmeter for troubleshooting.
As far as driving with that fuse pulled out, you should be OK. The outside temps are lower and you probably are not using the a/c. Just keep an eye on your temperature gauge.
But as for what is causing this problem, I don't know. When the car is turned off, the relays should not be able to energize because the 12 volts for this comes from the ignition switch in the ON position. Secondly the 12 volts then has to go through fuse 17 (step 1 above). Removing this fuse had no effect.
So my first assumption is that the relays could not be energized. Yet the 12 volts from fuse E (step 3 above) is getting to the fan motors, which says the relays have energized and closed the connections inside the relay. One could assume that the connection contacts in the relay have fused together to allow this. But this can't be the case because when you start the car, the fans stop.
I am hard pressed to visualize how a single component could cause this. I can visualize a senario involving a bad relay combined with a bad fan motor, but that theory has serious flaws.
Do the fans seem to be running at full speed? And both and both at the same speed? I would really like you to do my step 5 above, unplug one fan at a time.
Another thing I would like you to try requires the car to have an automatic transmission. If it does, unplug the relay labeled ASCD that is in the same box with the RAD FAN relays. Then, unplug the RAD FAN 2 relay and plug in the ASCD relay. Then do this with RAD FAN 3.
Do you have a voltmeter and can do basic measuring? I am thinking there is some wiring problem and we will need to use a voltmeter for troubleshooting.
12-01-2014, 11:07 AM
#10
My attempt to reset the ECU didn't change the behavior.
Both fans are definitely running at low speed when the car is off and you are correct that they stop right when the car is started.
Just an update to the issue - When I popped back in fuse E (RAD FAN 2) this morning the fans did NOT come on. I started and stopped the car and they remained off. After the morning drive the fans decided to come on again when the car was switched off.
The car is an automatic so I will be able to try the ASCD tests in the upcoming days and report the results, I will also attempt step 5. Unfortunately I don't have a voltmeter to do measurements.
Both fans are definitely running at low speed when the car is off and you are correct that they stop right when the car is started.
Just an update to the issue - When I popped back in fuse E (RAD FAN 2) this morning the fans did NOT come on. I started and stopped the car and they remained off. After the morning drive the fans decided to come on again when the car was switched off.
The car is an automatic so I will be able to try the ASCD tests in the upcoming days and report the results, I will also attempt step 5. Unfortunately I don't have a voltmeter to do measurements.
Last edited by Chron!cRAGE; 12-01-2014 at 11:12 AM.
12-01-2014, 02:07 PM
#11
not by any means a good meter, but will work if you NEED it
12-13-2014, 03:39 PM
#13
I have been out of the country for the past little while so I haven't had the chance to further troubleshoot the issue.
I did however isolate the problem to be related to the fusebox on the drivers side. What I found was that if I pulled up slightly on the fusebox the fans would stop spinning (with all the fuses in). If i pushed down on the fusebox the fans would start spinning. I have reason to believe that there is water inside that is shorting the fuses as this started happening right after I went to the carwash. Just some observations I noticed without actually taking apart the panel itself to check.
I did however isolate the problem to be related to the fusebox on the drivers side. What I found was that if I pulled up slightly on the fusebox the fans would stop spinning (with all the fuses in). If i pushed down on the fusebox the fans would start spinning. I have reason to believe that there is water inside that is shorting the fuses as this started happening right after I went to the carwash. Just some observations I noticed without actually taking apart the panel itself to check.
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