I family bought this car used about a month ago and didn't realize all of the electrical issues it had. Basically, the parking system light is on, low tire pressure is on, and the traction control light is on. Then every now and then while at a stop sign or stop light (when idling) the car will start beeping and the brake light will flash and then the ABS light will also come on. The ABS light sometimes comes on before the brake light, but when the brake light comes on the speedometer stops working and the fuel gauge will start moving back and forth.

I took it to the VW dealership and they said that it was the ABS module that needed replaced. However, I read the manual from front to back and it said that if the ABS module had any issues whatsoever, the ESP light would be on too. Another reason I doubt their diagnosis is that the ABS light isn't constantly on. Another mechanic suggested the ground wiring could be the issue.

Any thoughts on the problem?