stabilitrak

Hi. Wondering if anyone can help please. I'd the stabilitrak error come up with ABS & ESP lights come on some weeks ago. Garage replaced a coil (plastic was brittle and cracked) and then another bit which it fit into as that wasn't in good shape when they replaced the coil. The error message...

Can anyone tell me why I am getting this indication on the display: Service, StabiliTrak on, together with the engine yellow lamp and the traction control lamp both on the instrument cluster? I can't see anything for this ere StabiliTrak anywhere in the manual. Either way, it is effecting the...