TM-9-2350-277-20-1 Unit Maintenance Manual Volume 1 M113A3 M577A3 M1064A3 M1068A3 M58 Download
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TM 9-2350-277-20-1 COOLANT HEATER MALFUNCTIONS—Continued 0089 00 4Y 1. Does HEATER ON indicator come on in less than 3 minutes? YES NO GO TO GY (PAGE 0089 00-9) 5Y 1. Turn HEATER SWITCH to ON. Do not stop at OFF position. 2. Do blower and pump stay ON? YES NO 5YN 1. Replace heater ON/OFF/START switch. See task: Repair heater control box (WP 0737 00). 2. Verify no faults found. 6Y 1. Feel exhaust temperature. 2. Does heater continue to produce hot air for 10 minutes? YES NO 6YN 1. Shut off heater (see your -10). 2. Replace heater (WP 0728 00). 3. Verify no faults found. 7Y NOTE Heater will shut off prematurely if air inlet temperature is 60 degrees or above. This is normal. 1. Run heater on HI for 10 minutes. 2. Does heater continue producing hot air? YES NO 7YN 1. Shut off heater (see your -10). 2. Replace heater (WP 0728 00). 3. Verify no faults found. 8Y 1. Turn HEATER SWITCH to OFF. 2. Does blower remain on? YES NO 8YN 1. Heater does not purge. 2. Replace heater (WP 0728 00). 3. Verify no faults found. 9Y 1. Listen to heater until coolant pump and blower shut off. 2. Do coolant pump and blower shut off in less than 5 minutes? YES NO 9YN 1. Faulty heater flame detector switch. 2. Replace flame detector switch (WP 0734 00). 3. Verify no faults found. 0089 00-2