Rep Power: 0

I have a 96 Civic LX. The other day I noticed it was running a little bit hot but not over heating. Today I changed the thermostat as preventive maintenance. After that the car wouldn't start but would click from the passenger-side glove box area. Along with the drive 4 indicator light would flash. The service engine soon light would flicker. i had a mechanic try to scan the vehicle with no communications all fuses are good. Battery connection's are really good, changed the main relay which is what is clicking with no luck it still clicks. Last but not least. I checked over all my work by the thermostat to make sure i didn't break anything. Mechanic says it probably is the computer. Any suggestions let me know.

I also checked the ignition switch, electrical connectors which all have power. NEED HELP ASAP!!!