TM 9-2320-363-20-1 Table    3-1. Troubleshooting (Cont) Malfunction Test   or   Inspection Corrective    Action ELECTRICAL    SYSTEM   (CONT) Ether   Quick-Start Circuit    (Cont) Step    7. Disconnect ground    lead    from   ether    solenoid. Check    for   continuity    between ground    lead    and   ground. . If    continuity    is   indicated, replace ether   solenoid    (pages    4-65, 4-70). If   no   continuity   is   indicated,    repair   ground    lead    (page 3-2). Air   Dryer   Heater   Circuit 1. AIR DRYER HEATER NOT OPERATING. Step 1. Check reservoir heater/power take-off 15A   fuse. Step    2. Remove lead    18 . If   defective, replace 15A   fuse    (page    4-204). reservoir heater/power take-off 15A   fuse.    Check    for   +12 VDC at fuse    connector. . If   +12 VDC is   present, go   to   step   3.    If   no   voltage is   present, repair lead    18    to ignition run power    bus   (page    3-2). Step    3. Disconnect lead    94    from   air   dryer    drain   valve    heater. Check    for   +12 VDC at lead   94. . If   +12 VDC is   present, go   to   step   4.    If   no    voltage is present, repair lead 94 (page 3-2). Step 4. Disconnect ground lead from air dryer    drain   valve    heater. Check for continuity    between lead    and   ground. . If   continuity is   indicated, replace air   dryer   drain    valve heater (pages 4-552, 4-556). If   no   continuity    is   indicated, repair    ground lead    (page 3-2). 3-69