What do you hear when you crank? I suspect the battery, one or both, is the issue. Even if they look charged, they may not be able to start the engine after the glow plugs.

Where are you? weather may be a factor, depending on how long the glow plugs are on.

M

 

Thanks for the quick reply Mark. It doesn't crank at all, the starter does not appear to be engaging.

I am in Reno, Nevada. It has been in the 50s F during the day and down in the 30s at night for the last month, I did not notice a drastic change in weather when this issue occurred.

I am definitely NOT very familiar with this vehicle yet, so I am hoping that it is something silly that I am simply overlooking. Hope springs eternal!

 

Gut feeling, it's the battery. Enough power to run the electronics, but not enough to crank the starter. I had the same thing happen in our old jetta. A deep discharge had killed the battery.

 

I am not sure about your V6 TDI Mark but the V10 has two huge (Group 49) batteries. One is mounted under the front seat and controls the accessories, the other is mounted under the spare tire and starts the engine.

But my engine doesn't click, the starter does not engage. Even after trickle charging both batteries overnight. I can replace them, but I'm not convinced shotgunning $500 worth of batteries at the Touareg is going to fix my problem of the starter not clicking/engaging when I turn the key.

 

Check and make sure you have correct batteries. The one under the front seat is a group 49, but the one in the trunk is an H-8. The rear one has a much higher cold cranking amps rating. See this thread:
http://www.clubtouareg.com/forums/f93/v10-battery-information-75728.html

Also, when my batteries are dead nothing happens when you turn the key. It won't go "GRRR, Grrr, grrr, ruh" and quit. Remember that turning the key doesn't crank the engine. It signals the computer that you wish to start the car, then the computer fires up the glow plugs and when they are ready it send power to the starter. I think that if the power coming in isn't high enough, the computer won't send power to the starter at all.

Also, beware of cheap batteries. I tried cheaping out with the WalMart batteries and they died within 2 years. I could have gotten a pro-rated value on them for new WalMart batteries but I instead opted to go with Interstate batteries and they are doing fine after about 14 months.

 

Thanks Dave. The batteries in my Touareg are definitely not factory and they are on the list to get replaced with something better (I am partial to Odyssey batteries) but that was not the issue in my specific case.

I cannot say exactly what the problem was because I did a few things to the Touareg before it started. I added some Diesel 911 to the fuel tank since we had freezing temperatures in Reno, I disconnected and reconnected (but did not replace) the fuses and relays under the driver seat, and I tripped and then reconnected the yellow battery circuit breaker under the seat. After that strange ritual the vehicle started for me and seems to be fine now, although I have lost some confidence in it. My history is with Toyotas and there are a lot of aspects of the Touareg that just don't make a lot of sense to me.

 

See if there is someone local with a VCDS who can do a full scan for you. Something may show up that doesn't trip a CEL.

Keep an eye on the batteries though. A TDI needs lots of juice to crank when it's cold.

 

Any updates on this? It would appear that my starter battery is getting weak. It wouldn't start the truck twice now, so I'm going to be pricing out Interstates.

Also, a question for the Touareg gurus: Phaetons have an emergency start function, where you turn the key to the left (twice?) then to the right, and it will start the engine using the accessory battery. Does the Touareg also do this?

 

Any updates on this? It would appear that my starter battery is getting weak. It wouldn't start the truck twice now, so I'm going to be pricing out Interstates.

Also, a question for the Touareg gurus: Phaetons have an emergency start function, where you turn the key to the left (twice?) then to the right, and it will start the engine using the accessory battery. Does the Touareg also do this?

Yep

regards
Drag

 

Thanks for the input, guys.

 

Hi, yesterday I swapped the rear battery for a new one. From what I know even if the front battery is weak the truck should start using the rear which is the one it seeks to draw juice from when cranking.

It didn't.

It would turn rather weakly (like there is not enough juice) then stop cranking altogether. I proceeded to the left turn ignition routine and the car started immediately.

Later I placed a friend with a voltmeter to check the draw from the rear battery when cranking with the button (keyless) - where it should draw from the rear - it didn't draw anything and didn't start. However the car started immediately with the key in the ignition and the left turn routine. It DID DRAW from the rear batter that time (which baffles me).

I'm confused.

Isn't the left turn ignition routine designed to draw power from the accessory battery (front)? Why did it draw from the rear?

Why does the car need the left turn ignition routine to start when the main starting battery, the rear, is new (and charged - it has GREEN indication and 12.8 V static charge)?

Could a dead, low charged front battery create these kinds of symptoms?

The car is a 2005 V10.

 

Funnily enough my 2004 v10 does exactly the same thing, it always starts with the left turn trick though which uses the rear battery


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Hi, like I mentioned in the post I thought that the left turn trick draws current from the FRONT not the rear battery which is the regular starting battery. However it seems like under certain conditions that's not true. I will have to replace the accessory/under the seat battery too to see if that changes anything.

 

Mine starts with the underseat battery, which is the accessory or consumers battery, however, if the battery is too low to turn over I turn left for 5 seconds then right as normal and the rear battery starts the car


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But this is my point: The car should FIRSTLY attempt to start by using the REAR battery which is the primary starting battery not the under the seat accessory battery. The left turn trick should be activated if the rear battery is dead not the opposite.

Moreover, how do you know which battery starts the car? Have you measured the rear or front battery while the car was cranking? You seem pretty confident that your car starts with the rear not the front when you do the trick, I'm asking how can you be so sure that this is the case - it shouldn't as far as I understand the SSP298 Touareg electrics pdf (see image)?

Cheers.

 

Yes I have the wiring diagram too, I had a lot of trouble with the batteries and had it at a Bosch battery main dealer trying to sort out why the front battery was going flat.... that's a whole other thread, but my car definitely tries the front battery first then the rear works only with the left turn trick..... the service staff tested it at length


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Ok, so I'm not alone this. I think I'm going to replace my under the seat battery which is now at least 4 years old (that's how long I've owned the car). Maybe it's the original (I have no idea whether the previous owner had ever changed it). I don't think I have some draining issues with my car, it's more likely that the age of the batteries play a role in this. Changed the rear now I'll do the front and see how it goes.