There's a problem in the emissions system. You'll have to get it properly diagnosed in order to repair it.
The shift light on a Vauxhall Corsa is a light that indicates whether or not you're driving in low gear. It is typically located right on the dash.
Red
A spanner
Under The Steering Wheel
Turn light switch clockwise
check your door contact
May depend on model, especially if an early model. My Corsa has two.
1 reverse light and 1 tail light
easier to buy a complete new light mate
You can turn on and off the inside light by pulling in/out the switch for the front lights.
One of your Cat Convertors has a problem
whats mean dtc P1700 on zafira Z18XE.thanks