I have an 06 Jetta TDI Wagon (BEW), and after 6 months of storage, the battery was fried. After the new battery was installed, the battery symbol came up on the dash. I replaced the voltage regulator on the alternator, however the battery symbol on the dash stays lit. During an E-test I had the mechanic test the alternator and battery, and he said everything was working great. I've been driving it for a week now and I agree, the battery is holding a charge and alternator is working fine, except for the battery dash light.... and the fact that after exactly 10 minutes the ESP light comes on and the car starts driving/shifting rough (I assume this is limp mode?). If I turn the car off and back on, I get another 10 minutes of smooth driving. One note about the battery symbol on the dash, it is not full brightness. When I put the key in and turn it, the battery symbol appears dimly lit compared to the other symbols on the dash. When I start the car, it remains dimly lit. As I said, I've got a new battery, new voltage regulator in there. The code I get is 17911 - load signal from alternator terminal (P1503 implausible signal), and the snapshot shows the load signal at 0%. I've checked the wiring harness to the alternator based on suggestions from other forum posts, but it appears to be intact. When I read the voltage at the 2 plug harness at the alternator, it reads 14V on the wire that heads back to the dash (the wire that controls the alternator sits at 6-12V variable) I think this means that the wires are intact. One more test I did was to hack the connector and plug the alternator exciter wire in so the alternator was running, and read the voltage on the second pin coming off the alternator - it read 0V. Does this mean something in the alternator is fried, or is it supposed to be 0V So basically my next step is to try to replace the entire alternator, but I thought I'd check in first to see if somebody has any other tests I can run at the alternator 2 pin harness to further rule out a electrical issue (break or short somewhere between alternator and ECU) before I spend the cash on an alternator that may not be the solution!