my car is a 2010 6R 1.2 TSI CBZB MT with 225.000km on the IC.
Recently I've been monitoring charge voltage output with OBD11/VCDS and with a multimeter connected on the battery's terminals and on the cigarette's lighter port.
I'm not sure if the values I'm reading are absolutely fine or the anticipation of a component's failure (alternator or voltage regulator), but here they are:
- As soon as engine is started and cold, voltage is 14,1-14,3V. The colder ambient temperature is and the higher starting charge voltage is.
After around 10mins, it drops at 13,8-13,9V.
After 30mins / 1 hour of city traffic, it drops at 13,5-13,7V.
At this point, if I turn on cabin's fan to max speed, ac compressor and rear window's defroster, voltage drops at 13,2-13,4V.
Last sunday I checked and cleaned all the battery terminals positive and negative wires and the engine-chassis ground wires. After that, at first it looked like charge voltage raised more in the 14V area with warm engine and accessories turned ON. But after a few days, I noticed the situation got back down the same valures I wrote above.
What do you think?
Is there something else I should check?
I write the long-coding of my BCM, just in case any of you want to check if there is a bit incorrectly coded which might negatively affect charge voltage output:
3CB02BB808210000003800003D2B9CD00040670F60020000200000000000
If everything look absolutely fine and you think there's no problem to investigate, here comes the second answer.
Is there a way to increase charge voltage output?
I'd like to increase it of an amount of 0,4-0,5V in all conditions.
I've been thinking if it would be possible to swap my voltage regulator (06F 903 803 B) with another one with an higher voltage set-point, but I'm not sure if there is one compatible with my alternator (03F 903 023 D).
For example, I found on ETKA a voltage regulator from big engines installed on Polo and A1 (part n. 07K 903 803), it looks aesthetically identical to mine, but how can I know if it has an higher voltage set-point and if it's plug&play?
06F 903 803 B:

07K 903 803:

If someone knows more about this, any help would very much appreciated.
