TM 9-2320-209-20-3-1 7-53. AIR HORN AND SOLENOID REMOVAL AND REPLACEMENT. TOOLS: 7/16-inch wrench (2) 9/16-inch wrench 5/8-inch wrench 11/16-inch wrench SUPPLIES: None PERSONNEL: One EQUIPMENT CONDITION: Truck parked, engine off, handbrake set. a. Preliminary Procedures. (1) Open hood and right side panel. Refer to TM 9-2320-209-10. (2) Vent air system pressure. Refer to Part 2, para 13-20. (3) Disconnect battery ground cable. Refer to para 7-58. b. Removal. FRAME 1 NOTE Tag electrical connectors (1) before taking them off, to make sure they are put back in the right place. 1. Take two electrical connectors (1) off horn solenoid (2). 2. Using 5/8-inch wrench, unscrew coupling nut (3) and pull air tube (4) away from elbow (5). 3. Using 9/16-inch wrench, unscrew and take off elbow (5). GO TO FRAME 2 7-197