[JoeFromPA]

All,

I don't have an owner's manual and haven't been able to find this information online/via search.

I have an 07 TDI. Both batteries are ~2 year old top-end DEKA models and the vehicle has done several very long trips recently (i.e. over 100 miles straight highway).

During my first week or two of ownership, the voltage meter on the highway would pretty much stay spot on 14v and MAYBE dip to ~13.8 volts (if the gauge is linearly accurate).

A number of times it's run at 13.5v at highway cruising. Turning off/on additional draws doesn't seem to impact it. For example, running the front seat heaters are full blast doesn't impact it.

Just wondering what normal levels are for highway cruising.

 

[Singh]

Should be on 14

Run a scan and check if there are any low voltage drops recorded in the counter.
I am still running original batteries(both) in my 06 v10, expecting to change early next year- 8 yrs of service should be more than enough

 

[Niner]

13.7 or less is considered topped off and float charging. Immediately after a start up, 14.3 to 14.6 would be considered normal, or if heavy current draw devices are on, such as heated seats, heated defroster, heated mirrors, and head lights.

 

[JoeFromPA]

Gotcha. So a variation of .5 volts while driving (13.5-14.5 while actually running) is really nothing to be concerned about.

 

[Niner]

Gotcha. So a variation of .5 volts while driving (13.5-14.5 while actually running) is really nothing to be concerned about.

In the normal range, yes.