Table 5-1. Troubleshooting

TM 5-3610-220-14

Table 5-1. Troubleshooting - Continued

Malfunction

Probable Cause

Corrective Action

d. No light, fan runs normally. Buzzing

a. Tube failure.

a. Replace tube

sound is present.

b. High voltage breakdown.

b. Remove cover glass, disconnect one end

of lamp, and insulate lamp-lead with tape

Replace cover glass and dim room lights.

Power-up this light unit only and look into

lamp through fan hole for any visible arcing.

If any is present, open unit up and improve

spacing or repair broken insulation as

required. (Consult factory )

e. No light, no fan, no buzzing sound.

Fan blocked, which caused thermal fuse

Verify that fan turns freely by hand, and

to blow, or fan motor winding open.

check continuity of fan motor. Winding

should be 120 ± 20%.

f. Light unit blows fuse in power supply

Short in cable, connector or light unit.

Perform ohmeter check on cable connector

on a known "good" channel outlet.

pins as follows.

PIN A - Lamp should be open to all other

pins.

PIN B - Common should read 120 to Pin C

(fan) and 1 megohm to Pin D (trigger).

PIN C - Fan should read 120 to Pin B, and 1

megohm to Pin D.

PIN D - Trigger should read 1 megohm to

Pin B and C.

PIN E - Ground should read open to all pins.

5. Power Supply PS6-4.

WARNING

The power supply is connected to two (2) power circuits. Be absolutely sure the

BOTH supply circuits are disconnected before servicing the power supply.

a. Outlet dead. Light unit does not

a. Fuse blown due to circuit.

a. Replace circuit board and fuses. (Spare

produce light, and fan does not run when

parts kit #A4368.)

light unit is plugged.

b. Fuse blown due to main capacitor

b. Disconnect one side of capacitor from

short.

circuit, and measure across capacitor with

ohmeter. Meter should read open circuit

after 5 seconds charge time (either

direction).