All, I have an 04 V8 with 127,000 miles and have been having some issues with it as of recently. I changed a low beam bulb a week ago and upon finished I started the Treg and it wouldn't fully turn over. After a few tries it finally would but after that night it has to have a boost otherwise it will not turn over on its own. Also, the fans run at full speed and sound exactly like a jet engine and will stay running for 15-30 minutes after the engine is shut off even if I just start it then kill it instead of driving it. Replaced the fuel pump relay as I read on a thread referring to another vehicle this fixed the issue but it wasn't just the relay. Any ideas? I need it running ASAP so I can return to work.
04 4.2L won't start after headlight bulb change
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My first thought is that your battery sounds suspect. If it is over five years old I would replace it. BUT first...
I would measure the battery for static draw with the motor off and the fans off (pointless with them running). This will tell you if you have a big battery drain. I wonder if while working under the hood you inadvertently grounded something...might be fan circuit related given what you are experiencing.
Dead battery's generally result in some odd symptoms on these, but I have not read of fans running being one. That said fans running (for even 30 minutes) shouldn't drain the battery...that is why I suspect it might need replacement.
Lastly starting any car with a dead battery and then turning it off doesn't do you any favors as the battery will be even more flat.
I would measure the battery for static draw with the motor off and the fans off (pointless with them running). This will tell you if you have a big battery drain. I wonder if while working under the hood you inadvertently grounded something...might be fan circuit related given what you are experiencing.
Dead battery's generally result in some odd symptoms on these, but I have not read of fans running being one. That said fans running (for even 30 minutes) shouldn't drain the battery...that is why I suspect it might need replacement.
Lastly starting any car with a dead battery and then turning it off doesn't do you any favors as the battery will be even more flat.
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Well if it needs a jump to get started (if that is the boost you are referring to) than yes. I need to brush up on my Volts, Amps, and so forth, but I do know a battery can read good on volts (width of a door), but not have enough current (amps?) to turn over (only one foot of water coming through the door versus a five foot flood). Very intangible for me, but I have read this...
While it might need a new battery (due to needing a jump to get started) this might not solve your fan running problem, which is the fear I have with just throwing a new battery in it. In other words the real issue might be showing you that you also need a battery.
While it might need a new battery (due to needing a jump to get started) this might not solve your fan running problem, which is the fear I have with just throwing a new battery in it. In other words the real issue might be showing you that you also need a battery.
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I would search and read a good DIY on Touareg battery replacement here, as it isn't as easy as putting a new battery in older cars.
The parasitic draw test is a little complex, but here is a video with step by step process.
Note the Touareg doesn't shut off right away when you leave it...it has to go to sleep. if you decide to do this don't be near your key and leave your doors open until the truck shuts down (turns lights and dash off). Then don't open anything during the test as it will fry your multimeter.
It might be easier to replace the battery if older than 5 years (because it would need it anyways). Then see what happens.
Given that your fans are running when they shouldn't I would also look for any damage in the areas you worked under the hood. If nothing is apparent and the battery is replaced and the problem still persists then, you would need to start looking at components within this circuit to determine what is grounding.
Hope this helps.
The parasitic draw test is a little complex, but here is a video with step by step process.
Note the Touareg doesn't shut off right away when you leave it...it has to go to sleep. if you decide to do this don't be near your key and leave your doors open until the truck shuts down (turns lights and dash off). Then don't open anything during the test as it will fry your multimeter.
It might be easier to replace the battery if older than 5 years (because it would need it anyways). Then see what happens.
Given that your fans are running when they shouldn't I would also look for any damage in the areas you worked under the hood. If nothing is apparent and the battery is replaced and the problem still persists then, you would need to start looking at components within this circuit to determine what is grounding.
Hope this helps.
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old battery by the sound of it and your fans running is not helping.
14 volts when ??? When the engine is running ? This would then be the alternator pumping the battery. What is the battery gauge saying when you switch to aux but before you crank for ignition. This is what you need to know.
Back to the fans. Running for 20-30 mins after switch of is not normal you have a short somewhere in the system. The fans running full is a signal that something else is not working properly but what im not sure as it could be several things. Whats your coolant and oil temp telling you at full warm up .... is this normal ??
14 volts when ??? When the engine is running ? This would then be the alternator pumping the battery. What is the battery gauge saying when you switch to aux but before you crank for ignition. This is what you need to know.
Back to the fans. Running for 20-30 mins after switch of is not normal you have a short somewhere in the system. The fans running full is a signal that something else is not working properly but what im not sure as it could be several things. Whats your coolant and oil temp telling you at full warm up .... is this normal ??
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Re the fans - your coolant sensors - there are two one at the back of the engine and one at the bottom of the coolant radiator are faulty - mostly probably it is the one at the back of the engine - you can identify it via dealer computer. Cost $35 for the part and not that hard to replace.
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Fans running on after you have turned the car off is a not uncommon fault reported on here and as per DVMIS above is likely to be one of two coolant sensors being duff.
If your battery is more than 5 years old then replace it. Here's the how-to:
Changing the T1, T2 AND T3 battery, including both in the V10 - myTreg forums
If your battery is more than 5 years old then replace it. Here's the how-to:
Changing the T1, T2 AND T3 battery, including both in the V10 - myTreg forums
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So in summary: 1) Address if you have a battery issue, 2) Check coolant sensors, 3) If Coolant sensors are ok test thermostat in water pump.
Keep us posted what you find out and good luck.
Keep us posted what you find out and good luck.
If the thermostat was stuck closed you would see it on your coolant temperature indicator on your Dash, and the Treg should throw a error message in the MFI. If it was stuck open I would think the fans would not run at all. I'm going to guess it is one of your Engine Coolant sensors that is gone bad, typically its the one at the back of the engine. Same thing happening to me in my '04 V8. In my case the fans sounded as loud as a small Cessna taking off.
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