Scotty,
I have a 2017 golf Alltrack AWD. 6 speed ,87k-The battery started over heating and was spewing a stinky steam from the vents on the battery. I ran an alternator test with my innova 5512 scanner. Voltage was 14.7 I also used my manual load tester again I got a reading of 14.7 volts. I called VW dealer and spoke to service rep they said that 14.7 was normal. Could I have had a bad cells in the battery. I bought the car used 3 years ago and believe it was the second battery (a NAPA).
I replaced the battery and the voltage is still reading 14.7.
I took it for a short road test but probably not long enough to see if it will boil over. I will try that after I hear from you...
What do you think?
I said That if I ever wrote you I'd tell you that we have two VW's A 2017 Alltrack and a 2017 GTI (my wife's car) But we also have Two Reliable vehicles a 2015 Tundra and a 1991 Miata and yes the 1991 is more reliable then the Mexican Vw's...LOL
Have a great day!
Skidude.VT
Richmond Vermont.
14.7 volts sounds slightly high (usually 13.5 to 14.5 would be "normal") but I don't think another 2/10 of a volt would cause the battery to boil.
Rather than using the scan tool have you tried measuring the voltage directly at the battery terminals using a multimeter?
I drove it about 30 miles today with the new battery no problems.
I did attach a load tester directly to the terminals it read 14.7
I will try the multimeter tomorrow.
thanks for the reply