Problems with midpipe

[allrounda88]

As above
removed my old cat and replaced it with my megan racing midpipe
now my problem
after replacing it starting the engine and the ,,heat,, light comes on and goes off
so it switches on off on off
I also removed the cable from the air pump which I don\'t need anymore now
guys do you have answer for me what it could be?
maybe it is my oem ecu that can not handle that there is no cat?
the boost is normal under 1 bar

[philiwily]

The heat sensor that goes into the cat at the back sounds broken, get the 2 wires from the sensor and join them together.

Phil