Table 3-3. M43 detector unit troubleshooting table

TM 3-6665-225-12

Table 3-3. M43 detector unit troubleshooting table continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

If voltage is still more than 40 volts, substitute replacement electronic

module for electronic module in use (para 3-13); repeat test.

7. FLOWMETER INDICATIONS LOW

Step 1. Check that AIR INLET assembly is closed (fig. 2-5, A) and AIR OUTLET port is open (para 2-9a).

Step 2. Check that FLOWMETER is installed properly (para 2-9h).

Step 3. Check that AIR FILTER plug (7, fig. 1-2) is securely tightened.

Step. 4 Check air filter for deposits of foreign matter.

a. Unscrew plug (4, fig. 2-4).

b. Remove air filter and inspect for foreign matter deposited on black side of air filter.

c. Replace dirty air filter (para 2-7d(3)).

Step 5. Check for loose reservoir assembly.

Tighten reservoir assembly using D-ring (fig. 2-3),

Step 6. Check for loose or damaged detector cell.

Tighten bail (9, fig. 1-3).

Step 7. Prepare solution and install new reservoir assembly (para 2-7 b and c).

Step 8. Check that ball in FLOWMETER is not sticking.

a. Twist FLOWMETER (2, fig. 2-6) clockwise and remove it from AIR INLET assembly cover (4).

b. Hold FLOWMETER horizontal and check that ball moves freely by rocking FLOWMETER from side to side.

Step 9. Temporarily substitute replacement pump assembly in use (para 3-14).

If malfunction is corrected, leave replacement pump assembly installed, If not, reinstall original pump assembly.

Step 10. If air temperature is below 40F., perform startup procedures to warm up M43 detector unit (para 2-15j).

8. FLOWMETER INDICATIONS HIGH

Step 1. Check that air filter is not missing or defective.

a. Unscrew plug (4, fig. 2-4).

b. Install air falter if necessary (para 2-7d).

Step 2. Temporarily substitute replacement pump assembly for pump assembly in use (para 3-14).

If malfunction is corrected, leave replacement pump assembly installed. If not, reinstall original pump assembly.

9. METER INDICATION TOO HIGH, ERRATIC, OR MISSING

Step 1. Press in HORN VOL-BATTERY TEST knob (6, fig. 2-1) and release to check that switch does not stick.

Step 2. Press in ZERO ADJUST knob (5) and rotate counterclockwise to check for indication in blue zone on meter.

a. Hold ZERO ADJUST knob pressed in.

b. Press in hand crank (2), rotate crank clockwise 50 turns, and release it.

NOTE

Keep hand crank in down position, not pressed in.

c. Rotate ZERO ADJUST knob (still pressed in) for indication in blue zone, Release knob.

d. If necessary, press and reset. ZERO ADJUST knob after 5 minutes.

Step 3. Temporarily substitute replacement electronic module for electronic module in use (pars 3-13).

If malfunction is corrected, leave replacement electronic module installed. If not, reinstall original electronic

module.

Temporarily substitute replacement pump assembly for pump assembly in use (pare 3-14).

Step 4.

If malfunction is corrected, leave replacement pump assembly installed. If not, reinstall original pump assembly.

10. M43 DETECTOR UNIT DOES NOT RESPOND TO SIMULANT IN SENSITIVITY

CHECK BOTTLE WITHIN 5 MINUTES

Step 1. Temporarily substitute replacement detector cell for detector cell in use (para 3-12).

Repeat applicable procedures in paragraph 2-9a through p to check response to simulant in sensitivity check

Step 2.

bottle.

If malfunction is corrected, leave replacement detector cell installed. If not, reinstall original detector cell,

Step 3. Temporarily substitute replacement pump assembly for pump assembly in use (pare 3-14).

Step 4. Repeat applicable procedures in paragraph 2-9a through p to check response to simulant in sensitivity check

bottle.

If malfunction is corrected, leave replacement pump assembly.

Step 5. Temporarily substitute replacement electronic module for electronic module in use (para 3-13).

Step 6. Repeat applicable procedures in paragraph 2-9a through p to check response to simulant in sensitivity check

bottle.

If malfunction is corrected, leave replacement electronic module installed, If not, reinstall original electronic

module.

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