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CYCLE-SENTRY Diagnosis
152
Unit does not disengage starter
when engine is started
Defective starter
Test starter in Continuous Run
mode
Defective RPM sensor
Test 52A circuit
Open or grounded FS-1 or FS-2
circuit from RPM sensor to
CYCLE-SENTRY module
Test FS-1 or FS-2 circuit
Defective CYCLE-SENTRY module
Test CYCLE-SENTRY module
Unit turns On and reset switch
trips
Unit fails to start (normal indication)
Test for normal starting in
Continuous mode
Open 52 circuit from start relay to
CYCLE-SENTRY module
Test 52 circuit
Open 8S circuit from start relay to
starter
Test 8S circuit
Defective CYCLE-SENTRY module
Test CYCLE-SENTRY module
Standard 4-mode unit has no low
speed cool in automatic
start-stop mode (unit shuts Off
after High Speed Cool
Defective thermostat
Test thermostat
Open diode D6
Test D6 diode
Standard 4-mode unit will not
initiate start from defrost
Open 29 circuit
Test 29 circuit to PC board
Open D11 diode or R9 resistor, or
29T circuit on PC board
Test D11 diode or R9 resistor and
29T circuit on PC board to
thermostat
Defective thermostat
Test unit thermostat
Unit will not initiate start if engine
temperatures drop below 60.0 F
(15.5 C)
Defective block temperature
thermostat
Test block temperature thermostat
Open 8B circuit to block
temperature thermostat
Test 8B circuit
Open 7A circuit from block
temperature thermostat to run relay
Test 7A circuit
Unit will not stop when load
temperature thermostat is
satisfied
Defective block temperature
thermostat switch
Test block temperature thermostat
switch
Defective load temperature
thermostat
Test load temperature thermostat in
Continuous Run mode
Engine temperature below 120 F
(49.0 C)
Check engine temperature after
warm up
Battery not charged
Charge battery
Defective battery sentry
Replace battery sentry
Charging system faulty
Correct charging system
Condition
Possible Cause
Test Procedure
Summary of Contents for 914970
Page 3: ...3...
Page 10: ...Table of Contents 10...
Page 40: ...Operating Instructions 40...
Page 82: ...Electronic Controls 82...
Page 92: ...Electrical Maintenance 92...
Page 124: ...Refrigeration Maintenance 124...
Page 140: ...Hilliard Clutch Maintenance 140...
Page 160: ...Refrigeration Diagrams 160...
Page 163: ...Index 163 W wiring 85 wiring diagrams 165...
Page 164: ...Index 164...
Page 166: ...Wiring and Schematic Diagrams Index 166...
Page 167: ...167 Cab Control RD Wiring Diagram...
Page 168: ...168 RD w o Thermostat Cab Control Schematic...
Page 169: ...169 RD Cab Box Wiring Diagram...
Page 170: ...170 RD Cab Control w Thermostat Schematic Diagram...
Page 171: ...171 RD 50 STD 3 Phase Wiring Diagram Page 1 of 2...
Page 172: ...172 RD 50 STD 3 Phase Wiring Diagram Page 2 of 2...
Page 173: ...173 RD 50 STD 3 Phase Schematic Diagram Page 1 of 2...
Page 174: ...174 RD 50 STD 3 Phase Schematic Diagram Page 2 of 2...
Page 175: ...175 RD 30 STD Wiring Diagram Page 1 of 2...
Page 176: ...176 RD 30 STD Wiring Diagram Page 2 of 2...
Page 177: ...177 RD 30 STD Schematic Diagram Page 1 of 2...
Page 178: ...178 RD 30 STD Schematic Diagram Page 2 of 2...
Page 179: ...179 RD 30 C S Wiring Diagram Page 1 of 2...
Page 180: ...180 RD 30 C S Wiring Diagram Page 2 of 2...
Page 181: ...181 RD w CYCLE SENTRY Schematic Diagram Page 1 of 2...
Page 182: ...182 RD w CYCLE SENTRY Schematic Diagram Page 2 of 2...
Page 183: ...183 RD 50 C S 3 Phase Wiring Diagram Page 1 of 2...
Page 184: ...184 RD 50 C S 3 Phase Wiring Diagram Page 2 of 2...
Page 185: ...185 RD w CYCLE SENTRY Schematic Diagram Page 1 of 2...
Page 186: ...186 RD w CYCLE SENTRY Schematic Diagram Page 2 of 2...