What was found
(CAN) DURING A FLT, PILOT REPORTED AILERON AUGMENTATION MODE SYS INOPERATIVE. A LEARJET GPWS/WINDSHEAR SYS INSTALL COMPLETED ON 09/30/94 REMOVED & A NEW TAWS 8000 SYS UPGRADE INSTALLED ON 05/29/04. FURTHER INVESTIGATION REVEALED THAT DURING GPWS/WINDSHIELD UPGRADE TO TAWS 8000, GPWS AUX BOX (E374) HAD BEEN REMOVED AS REQUIRED BY DRAWING WHILE REMAINING WIRES CAPPED & STOWED & DID NOT TAKE INTO CONSIDERATION USEFULNESS OF WIRES F23B22, TW89A22, F25B22, TW91A22 TO SPOILERON COMPUTER. A REQUEST FOR ENGINEERING SUPPORT WAS FORWARDED & A REVISED DRAWING 1003421 REV B PROVIDED TO CORRECT ORIGINAL DRAWING AND WIRE OVERSIGHT INCLUDING DATA APPROVAL DOCUMENTED ON 10/22/04.