Abs traction control

[Phily123]

Hi just bought a q7 2008 went to pick up after brakes and pads fitted and abs and esp light keeps coming on while driving and sort of locking up .changed abs sensor and wheel barring seemed to be ok for 2 days then bang back to square one so just been to garage checked tyre pressure and passenger side both 6 psi lower inflated to same as drivers  side abs and traction light disappeared.....would this cause the lights