TM  10-3930-638-24&P 2-32.   HORN   AND   BACK-UP   ALARM   MAINTENANCE   (cont) b. Horn Switch. This task covers: a.  Removal d.  Testing b.  Cleaning e.   Installation/Replacement c. Inspect ion INITIAL  SETUP TOOLS EQUIPMENT CONDITION No. 1 Common Organiza- NSN  4910-00-754-0654 Paragraph Condition tional Maintenance Tool Kit Engine  off. Description MATERIALS   PARTS Cleaning Solvent P-D-680 Clean  cloths 2-33b Battery  ground  cable  disconnected. STEP LOCATION ITEM ACTION REMARKS REMOVAL 1 Steering  column a. Cover (1) and Remove Depress  and  rotate  counterclockwise  to and wheel button  (2) release  from  tabs  on  base  plate  (7) b.  Contact  cup  (3),  spring  Remove (4)  and  spring contact (5) c. Three tapping screws Remove (6) and base plate (7) d. Harness connector (8) Grasp  and  pull From column terminal (l I ) e. Grommet (9) Remove From  instrument  panel CLEANING WARNING Dry cleaning solvent (P-D-680), used to clean parts is toxic and flammable. Wear protective goggles and gloves and use only in a well ventilated area. Avoid contact with skin, eyes, and clothes and don’t breathe vapors. Do not use near open flame or excessive heat and don’t smoke when using it. Failure to do so could cause serious injury. If you become dizzy while using cleaning  solvent,  get  fresh  air  immediately,  and  get  medical attention. If contact with skin or clothes is made, flush with large amounts of water. If contact with eyes is made, wash eyes with water  immediately,  and  obtain  medical  aid  immediately. 2-177