TM 5-5420-226-20-1 DETAILED TROUBLESHOOTING PROCEDURE SUPPORT SYSTEM -  VEHICLE LIGHTING Symptom-6 1 (Continued) .-P Check    front    accessory harness (CKT   22)   at  bulkhead 1 disconnect for   electrical power. Second Technician (Operator’s Station) l   Set   MASTER BATTERY switch OFF. First Technician (Rear Grille Doors) l   Reconnect rear    accessory harness connector (GKT 22) to   le~    taillight assembly. First and    Second Technicians (Rear Grille Doors) l   Install    transmission shroud (page 9-6). First Technician (Commander’s Station) . l   Displace front accessory harness connector from bulkhead disconnect (page 10-269). l   Connect red   probe    of   meter to   contact B  (CKT 22)   of front accessory harness connector and    black probe to ground. Second Technician (Operator’s Station) l   Set   MASTER BATTERY switch ON. l   Press   and    hold    brake   pedal. First Technician (Commander’s Station) l   Check   if  meter   indicates 18  to   30  volts    dc   while    brake pedal is   pressed. / Does    meter indicate 18  to   30   volts    dc? w BULKHEAD DISCONNECTS (ON   RIGHT BULKHEAD) FOR   CLARITY QUADRANT ASSEMBLIES NOT   SHOWN I l    Inspect rear   accessory harness for   bent/broken connector contacts or   loose CKT   22   wire   at   rear   of connectors. l   Repair    connectors if  defective (page 10-298). l   If  connectors are   not defective, notify support maintenance of   a  defective rear   accessory harness. l   Install    front    accessory harness connector at bulkhead disconnect (page 10-270). TA1073OO . — 4-611