New Holland CX720 Repair Manual page 3707

E0159-03-Grain Bin Full sensor Shorted To High Source
(K.60.B.95.80 - G.30.B.54)
CX720 Series 1238 and above, CX740 Series 1238 and above, CX760 Series 1238 and above, CX780 Series 1238 and above, CX820 Series 1238 and
above, CX840 Series 1238 and above, CX860 Series 1238 and above, CX880 Series 1238 and above
E0159-03 - Grain Bin Full sensor Shorted To High Source
NOTE: This troubleshooting chart is for CX combines Series 1238 and above.
Cause:
The grain bin sensor (S-28 & S-29) circuit is shorted to high voltage.
Possible failure modes:
1. Sensor supply or ground wiring shorted to 12 volts.
2. Controller internal failure (internal regulator failure).
Solution:
1. Enter the Infoview monitor - "Diagnose info" screen.
Select "Clean Grain" sub menu.
Select "Grain Bin Full sensor" and check voltage range.
The normal voltage range is 0 - 4.9 volts.
The proper voltage range with both switches neutral is approximately 2.5 volts.
The proper voltage range with the ¾ full switch depressed is approx. 3.3 volts.
The proper voltage range with both bin switches depressed is approx. 3.7 volts.
A. If the voltage reading is high out of range (> 4.9 volts), continue with Step 2.
B. If the voltage reading is within the proper limits, continue the troubleshooting at step 11.
NOTE: Visually inspect the wiring harness and connectors. Verify that the connector was fully installed. Inspect
the terminals and wires at the connector for pushed back or corroded terminals or damaged wires. Flex the
harnesses involved to reveal intermittent breaks or shorts in the wiring concerned.
2. The voltage reading on the InfoView monitor is high. Disconnect the grain bin full sensor S29 connector X109.
A. If the voltage drops to 0 - 4.9 volts, the short is in the reference ground wire for the circuit. Continue with
step 3.
B. If the voltage remains high on Infoview monitor, continue with Step 4.
3. Disconnect the main frame harness from the front frame harness at connector X008.
A. Use a multimeter to check for voltage on each half of connector X008 pin 14. After determining which wire
is shorted to high voltage, use the schematic to trace that wire until the source of the short is found.
4. The voltage reading on the InfoView monitor is high. Disconnect the grain bill full sensor S29 connector X109.
Use a multimeter to check for continuity between connector X109 pin A and chassis ground.
A. If continuity is found, continue with step 7.
B. If no continuity is found, continue with step 5.
5. Disconnect the grain tank harness from the main frame harness at connector X009. Use a multimeter to check
for continuity between the harness end of connector X009 pin H and chassis ground.
A. If there is continuity, the open circuit is in the grain tank (GT) harness between connector X009 pin H and
connector X109 pin A wire 443 blue. Locate the open and repair.
B. If there is no continuity to ground, continue with step 6.
6. Disconnect the main frame harness from the front frame harness at connector X008. Use a multimeter to check
for continuity between the harness end of connector X008 pin 14 and chassis ground.
CROP PROCESSING - STORING AND HANDLING Grain storing
2 4/7/2006
K.60.B / 73