TM-9-2320-387-24 HMMWV Direct Support & General Support Maintenance Manual Volume 1 Download
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TM 9-2320-387-24-l ENGINE COOLING L KNOWN INFO FAN BLADES OK SERPENTINE BELT OK FAN DRIVE OK POSSIBLE PROBLEMS FAN WIRING TIME-DELAY MODULE CONTROL VALVE FAN TEMPERATURE SWITCH PCB KNOWN INFO FAN BLADES OK SERPENTINE BELT OK DRIVE ENGAGES POSSIBLE PROBLEMS FAN WIRING TIME-DELAY MODULE CONTROL VALVE PCE KNOWN INFO =AN OK SERPENTINE BELT OK FAN ENGAGES AND DISENGAGES POSSIBLE PROBLEMS FAN WIRING TIME-DELAY MODULE FAN TEMPERATURE SWITCH DISCONNECT WIRE 458A FROM THE FAN TEMPERATURE SWITCH, JUMPER 458A TO 4588. DOES THE FAN DISENGAGE? TEST OPTIONS 1. STUICE-R TEST 91 (Page 2-508) MEASURE THE CONTINUITY THROUGH THE FAN TEMPERATURE SWITCH. THE SWITCH SHOULD BE OPEN AT TEMPERATURES ABOVE 215°F (102°C) AND CLOSED BELOW. IS THE SWITCH OK? DISCONNECT WIRE 4588 FROM THE FAN TEMPERATURE SWITCH. WITH THE ENGINE RUNNING, IS THE FAN ENGAGED? DIAGNOSTIC FLOWCHART TEST OPTIONS REASON FOR QUESTION Disconnecting 4588 from the switch simulates a hot engine. _ REASON FOR QUESTION Having battery voltage on 458A simulates a cold engine. I 2. MULTlMmR REASON FOR QUESTION To check the switch operation. Ideally. check the switch for open and closed operation.