2004 B6 Overheating / Fans not working issue
#1
05-06-2013, 05:01 PM
2004 B6 Overheating / Fans not working issue
So basically when i am in traffic or idle, my temperature gauge rises to 3/4 and My fans do not turn on, even when i put the a/c it blows hot air and the electric fan doesn't run either. Coolant doesn't seem to be missing and its on its proper level.
No codes on vag com except when I run a coolant fan output test nothing happens at all.
When I do start driving again my temperature returns to the midway point until I do idle for too long again.
How can I test my fans? to see if they work from a 12 v source or what could be the issue here.
thermostat seems be working fine.
in the fuse box next to my door it shows radiator as fuse 9 but theres no way any fuse can stay in as there is no contact on the back of this slot.
No codes on vag com except when I run a coolant fan output test nothing happens at all.
When I do start driving again my temperature returns to the midway point until I do idle for too long again.
How can I test my fans? to see if they work from a 12 v source or what could be the issue here.
thermostat seems be working fine.
in the fuse box next to my door it shows radiator as fuse 9 but theres no way any fuse can stay in as there is no contact on the back of this slot.
Last edited by jafferman; 05-06-2013 at 05:09 PM.
#4
05-06-2013, 06:54 PM
In the ecu box? There was two fuses on that a large 40amp and a 20 amp both were fine. Or is there another fuse I am missing outside the ecu box
#5
05-06-2013, 06:58 PM
How do I purge the system? Or force the fans to turn on
#6
05-06-2013, 11:25 PM
Fan Control Module
A/C will not work with out cooling fans. NO fans NO A/C.... Most likely the fan control module on the Radiator Support aka Lock Carrier. Common Failure on the B6s. I have done 2 this month.
#7
05-07-2013, 10:57 AM
Is there a way to test this? Or even the relays at all? on the output tests in vagcom for the cooling fan, I Do not hear any clicks or anything
#8
05-08-2013, 11:07 AM
So basically when i am in traffic or idle, my temperature gauge rises to 3/4 and My fans do not turn on, even when i put the a/c it blows hot air and the electric fan doesn't run either. Coolant doesn't seem to be missing and its on its proper level.
No codes on vag com except when I run a coolant fan output test nothing happens at all.
When I do start driving again my temperature returns to the midway point until I do idle for too long again.
How can I test my fans? to see if they work from a 12 v source or what could be the issue here.
thermostat seems be working fine.
in the fuse box next to my door it shows radiator as fuse 9 but theres no way any fuse can stay in as there is no contact on the back of this slot.
No codes on vag com except when I run a coolant fan output test nothing happens at all.
When I do start driving again my temperature returns to the midway point until I do idle for too long again.
How can I test my fans? to see if they work from a 12 v source or what could be the issue here.
thermostat seems be working fine.
in the fuse box next to my door it shows radiator as fuse 9 but theres no way any fuse can stay in as there is no contact on the back of this slot.
Faulty water pump, Restriction in Cooling System (plugged radiator or stuck closed thermostat) or inoperative cooling fans.
Easiest way to check the fans an see if they have a "12V Source" would be to put both climate control head temps. to LO and blower fan to MAX speed and see if fans turn on. The fans should kick on immediately after putting the HVAC system into A/C MAX. (Look down at the A/C Compressor Cluth to see if it engages/spins)
01 Engine Control Module Faults that would cause a Cooling Fan Issue would be a coolant temp sensor (G62) fault, or a Open Circuit/Short to Ground Fault for cooling fans (V1 or V2, ect) or even a Thermostat Fault on a B6. The ECU is checking fuses and relays all the time, if a fuse pops, then a OPEN CIRCUIT fault would be throw, check engine light would be on. If the G62 is faulty, the ECU would throw a CEL on, and if the T-stat is Faulty, the ECU would throw a CEL.
No Fans, and No faults found in 01, you would have a faulty Fan Control Module.
Now if the fans do turn on (with MAX AC), then I would put the climate control head back to lick 72 degrees and then let the vehicle run at idle. If the temp gauge on the cluster move past the middle marker, and the fans DO NOT kick in, I would be checking the G62 measuring value block in 01 Engine and then check G62 reading in 17 Instruments (cluster). If both readings are the same, I would perform a needle swipe test, to make sure the cluster needles are working properly. If Needles work correctly and G62 readings seem correct, then I would be looking for a water pump issue pr blockage in cooling system.
Good Luck
Last edited by 4ringking; 05-08-2013 at 11:14 AM.
#9
05-08-2013, 05:38 PM
#1 Vehicle overheats at idle. This would be cause by one of a few things:
Faulty water pump, Restriction in Cooling System (plugged radiator or stuck closed thermostat) or inoperative cooling fans.
Easiest way to check the fans an see if they have a "12V Source" would be to put both climate control head temps. to LO and blower fan to MAX speed and see if fans turn on. The fans should kick on immediately after putting the HVAC system into A/C MAX. (Look down at the A/C Compressor Cluth to see if it engages/spins)
01 Engine Control Module Faults that would cause a Cooling Fan Issue would be a coolant temp sensor (G62) fault, or a Open Circuit/Short to Ground Fault for cooling fans (V1 or V2, ect) or even a Thermostat Fault on a B6. The ECU is checking fuses and relays all the time, if a fuse pops, then a OPEN CIRCUIT fault would be throw, check engine light would be on. If the G62 is faulty, the ECU would throw a CEL on, and if the T-stat is Faulty, the ECU would throw a CEL.
No Fans, and No faults found in 01, you would have a faulty Fan Control Module.
Now if the fans do turn on (with MAX AC), then I would put the climate control head back to lick 72 degrees and then let the vehicle run at idle. If the temp gauge on the cluster move past the middle marker, and the fans DO NOT kick in, I would be checking the G62 measuring value block in 01 Engine and then check G62 reading in 17 Instruments (cluster). If both readings are the same, I would perform a needle swipe test, to make sure the cluster needles are working properly. If Needles work correctly and G62 readings seem correct, then I would be looking for a water pump issue pr blockage in cooling system.
Good Luck
Faulty water pump, Restriction in Cooling System (plugged radiator or stuck closed thermostat) or inoperative cooling fans.
Easiest way to check the fans an see if they have a "12V Source" would be to put both climate control head temps. to LO and blower fan to MAX speed and see if fans turn on. The fans should kick on immediately after putting the HVAC system into A/C MAX. (Look down at the A/C Compressor Cluth to see if it engages/spins)
01 Engine Control Module Faults that would cause a Cooling Fan Issue would be a coolant temp sensor (G62) fault, or a Open Circuit/Short to Ground Fault for cooling fans (V1 or V2, ect) or even a Thermostat Fault on a B6. The ECU is checking fuses and relays all the time, if a fuse pops, then a OPEN CIRCUIT fault would be throw, check engine light would be on. If the G62 is faulty, the ECU would throw a CEL on, and if the T-stat is Faulty, the ECU would throw a CEL.
No Fans, and No faults found in 01, you would have a faulty Fan Control Module.
Now if the fans do turn on (with MAX AC), then I would put the climate control head back to lick 72 degrees and then let the vehicle run at idle. If the temp gauge on the cluster move past the middle marker, and the fans DO NOT kick in, I would be checking the G62 measuring value block in 01 Engine and then check G62 reading in 17 Instruments (cluster). If both readings are the same, I would perform a needle swipe test, to make sure the cluster needles are working properly. If Needles work correctly and G62 readings seem correct, then I would be looking for a water pump issue pr blockage in cooling system.
Good Luck
When I put it to LO and fan speed max I hear air blowing but the cooling fan doesn't spin at all. Doesn't seem like it is getting 12V. I actually have not seen the rad fan go off either, but when I am in motion the engine doesnt overheat only on idle or in traffic.
Engine Control Module Faults, I have zero codes that show up or any indication. I ran an output test in Vagcom for cooling fans I do not hear anything not even clicking from any relays.
Do signs point to the Fan Control Module? Or because the output test doesn't make any of the relays click should I be focusing on that?
Thanks!
Last edited by jafferman; 05-08-2013 at 05:41 PM.