New Holland CX720 Repair Manual page 3930

B. If the motor coil resistance is within specification continue with Step 12.
12. Replace the fan/reverser relay K17 with a known good relay. Connect X090 and operate fan.
A. If the fan is now working troubleshooting is complete.
B. If the fan still does not work continue with Step 13.
13. Again disconnect fan speed connector X090. Key switch on, engine running. Push the fan speed rocker switch
to increase fan speed. Use a multimeter to measure the voltage between connector X090 pin A and chassis
ground.
A. If 12 volts is read continue with Step 14.
B. If 12 volts is not read continue with Step 16.
14. Key switch on engine running. Pull the fan speed rocker switch to decrease fan speed. Use multimeter to
measure the voltage between connector X090 pin B and chassis ground.
A. If 12 volts is not read continue with Step 15.
15. Disconnect connector X023. Key switch on, engine running. Pull the fan speed rocker switch to decrease fan
speed. Use multimeter to measure the voltage between connector X023 pin 19 and chassis ground.
A. If 12 volts is read the open is between connector X090 and connector X023 wire 761 gray in the lower
frame harness. Locate the open and repair.
B. If 12 volts is not read the open is between connector X023 and the next splice in wire 761 gray in the front
frame harness.
16. Disconnect connector X023. Key switch on, engine running. Push the fan speed rocker switch to increase fan
speed. Use a multimeter to measure the voltage between connector X023 pin 22 and chassis ground.
A. If 12 volts is read the open is between connector X023 and connector X090 wire 763 white in the lower
frame harness.
B. If 12 volts is not read continue with Step 17.
17. Disconnect connector X031. Key switch on, engine running. Push the fan speed rocker switch to increase fan
speed. Use a multimeter to measure the voltage between connector X031 pin 12 and chassis ground.
A. If 12 volts is read the open is between connector X031 and connector X023 wire 763 white in the front
frame harness.
B. If 12 volts is not read the open is between connector X031 and relay base terminal 4 on relay K17, wire
763 white in the cab main harness.
18. Disconnect connector X090 at the fan speed motor. Use a multimeter to check for an internal short to ground
between both pin A and B.
A. If short to ground is found replace motor.
19. The reverser motor actuator is bound up.
A. See the appropriate service manual chapter for repair.
20. The reverser operates in one direction only. Fault codes indicate a short to ground. Disconnect the reverser
motor connector X080.
A. Measure the resistance on connector X080 between pin A and pin B. The proper resistance range for the
coil is 4.0 - 8.0 ohms. If out of specification replace reverser motor.
B. If the motor coil resistance is within specification continue with Step 21.
21. Measure the resistance on connector X080 between pin A and chassis ground. Flex the feeder and front frame
harnesses while making this check.
A. If no continuity to ground is found erase the fault code and continue operation.
CROP PROCESSING - CLEANING Primary cleaning
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