Chevrolet Repair: 1998 blazer flasher sound, gm passlock, keyless start

Question
i have a 1998 blazer flashing sound coming from a black box that is about 3"x4" and has a lot of wires going into. and now after moving it around now the truck is rough starting and doesn't stay running

Answer
Hi Bill....where is the box located...there are several differant ones in that truck...if after moving it truck runs rough..check the wires comming from it to be sure nothing is frayed and touching ground anywhere...also check the connection on it for corrosion...make sure connector is tight...does truck have alarm system, could box be for that...does truck have keyless start...could it be for that...if it is keyless start box or alarm is it factory installed or aftermarket...if alarm you may need to go to someone that installs them as they have a complicated wiring system into the GM passlock system in order to find out what may be wrong...hope this helps