TM 10-6640-215-13 Table 4-2.  Troubleshooting MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION WARNING Before    performing    any    maintenance    actions    on    electrical equipment,  ensure  all  electrical  power  has  been  turned  off. Failure to comply with this warning may result in serious injury or death. NOTE Refer to electrical schematic diagram FO-1 located in back of manual when troubleshooting electrical system. 1. NO  ELECTRICAL  POWER  TO  LABORATORY  (GENERATOR  OUTPUT  SWITCH  ON  AND  POWER  CABLE PROPERLY CONNECTED). WARNING Do not come in contact with main power cable connections on generator   set   with   power   applied   to   laboratory.      Death   or serious injury may result. Step 1. Place generator output switch OFF and shut generator down. Step 2. Disconnect power cable from both generator and petroleum laboratory. Step 3. Using multimeter, check power cable for open or shorted leads. If open or shorted lead is found, replace power cable.  See paragraph 4-15. 2. FLUORESCENT LIGHT BULB FAILS TO LIGHT (OTHER BULBS IN FIXTURE LIGHT). Step 1. Replace starter with known good starter. Bulb still fails to light. Step 2. Replace bulb with known good bulb. Bulb still fails to light. Replace ballast.  See paragraph P16. 3. EMERGENCY LIGHT FAILS TO COME ON WHEN NORMAL POWER IS LOST. Step 1. Check appropriate emergency light switch ON. Light switch ON. Step 2. Replace ballast in appropriate ballast box.  See paragraph P17. 4-13