Please help, strange problems.

[Richiew1986]

Hi, I bought an Astra J a couple of weeks ago, since then a few problems have surfaced. It started after I removed the battery to replace the air bag and steering wheel. Code 16 came on, found that a bulb had blown so replaced that, code gone but still no brake lights. I then noticed that the brake lights would illuminate with the reverse light.

Today while driving I noticed that the brake lights are coming on but not when I press the pedal, seems to be in response to slowing down, then coming of when accelerating. maybe unrelated but my remote locking keyfob stopped working too.  I've never came across this problem before and think it's really strange, hope someone can help me shine some light on it. Really would appreciate some expertise on this, I'm going my wits end with it.

Looked on Opcom and there does seem to be some trouble codes. 

U0140-71 Lost communication with Body Control Module - Invalid data

C0277-06 Brake Pedal Position sensor circuit- Low voltage/open

C0277-4B Brake Pedal Position sensor circuit- Calibration not learned

C0890-003 Control module voltage reference output 3 circuit - undervoltage