What was found
REPORTED THAT THE WING ICE LIGHT C/B SWITCH TRIPS AFTER BEING IN (ON) POSITION FOR 3-4 MINUTES. TROUBLESHOOTING REVEALED THAT A 3 AMP C/B HAD BEEN INSTALLED IN A 7 AMP CIRCUIT AT POSITION 33CB15. INSPECTING THE OTHER C/B SWITCHES REVEALED THAT POSITION 33CB6, 33CB11 AND 33CB32 WERE ALL WRONG AMPERAGE C/B. THE C/B WERE REMOVED AND REPLACED IN THEIR CORRECT RESPECTIVE CIRCUITS AND THE SYSTEMS OPERATIONAL CHECKED. RESEARCH OF RECORDS REVEALED NO WORK HAD BEEN ACCOMPLISHED ON THE AFFECTED CIRCUITS AT ANY TIME SINCE THE AIRCRAFT WAS NEW. LEADING TO THE CONCLUSION THAT THE C/B WERE INCORRECTLY INSTALLED DURING PRODUCTION. MFG TECHNICAL SUPPORT WAS NOTIFIED AND IS CONDUCTING AND INVESTIGATION AT THIS TIME.