Car Alarms: Alarm Install/Gas Light, toyota celica, fuel light

Question
I own a 2005 Toyota Celica GT. Yesterday, I had installed an Autopage RF-220 alarm, by a supposedly professional shop here in town. After picking up my car, I noticed that my fuel light was on, even though I had just filled up. Now the light won't go off. Nothing has been done except for the alarm. It wasn't on when I dropped off the car, and was on when I picked it up. The shop is claiming no responsibility for it, even though they were the only ones to touch it. Is this an easy fix, what is causing this problem?

Answer
They caused the problem. May have a wire comnnected
to an improper wire or circuit, tripping the
light in the instrument cluster.

They either should disconect wires, 1 at a time to
determine which is the inadvertant trigger and
diode isolate this connection, or
contact Toyota, have them do it, and give the
bill to the installer, through your lawyers office,
or you can sue they're insurance company for the
damages directly.

Hot potato I know, but they caused this issue.
They need to stand up and cop to it.

Let me know what they say.

ALARMTEK