172 sticks at 1500rpm with immobiliser light one??

[midge]

test drove a 172 earlier and it kept cutting out at very low speeds and at low rev's, and it also 3 times just stopped doing anything at all but the rev's would stick it about 1500 with the immobiliser light on? turning it off and restarting sorted it out..

Whats the problem?

 

[Jay Payne]

Check all the fuses and earths, had strange immobiliser light problems on one of mine before