How did they tell it was not bad? I bet it probably is, if the puter is flagging the code. I'm not sure how to turn off the light. You "might" be able to reset it by unhooking the battery for a few seconds and reconnecting, but not sure on that model. But it will probably trip again. I'd try to find the real problem, so the light doesn't come on. I'm curious why they think it's not the cat, if the puter flagged it as bad. If you don't want to get a cat, I'd just ignore the light, or stick some tape over it...MK