Engine Control Unit (ECU) Diagnostic Codes

NOTE: For technical assistance on engine codes, see your Technical Manual or John Deere dealer.

When error is detected, an error number will display on tachometer. If more than one error is detected, each number will display for 6 seconds and then next error number(s) will be displayed.

Fault Code Description
18 Coolant Temperature Input Voltage too High
19 Coolant Temperature Input Voltage too Low
21 Sensor Supply Voltage too High
22 Sensor Supply Voltage too Low
25 Manifold Air Temperature Input Resistance too High
26 Manifold Air Temperature Input Resistance too Low
28 Engine Control Unit Failure
31 Rack Measurement Error (Engine Off)
34 Rack Position Error
35 Rack Position Voltage too High
36 Rack Position Voltage too Low
37 Fuel Temperature Input Voltage too High
38 Fuel Temperature Input Voltage too Low
41 Start Signal Missing
42 Engine Overspeed
44 Auxiliary Speed Input Error
46 Start Signal Always Active

 

OUO1078,0000442 -19-23MAY05-1/2

Fault Code Description
53 Rack Instability
54 Power Problem To ECU
61 Coolant Level Low
62 Coolant Temperature Warning Threshold
63 Coolant Temperature Above Shutdown Threshold
66 Coolant Temperature Above Warning Threshold
68 Fuel Derate Active For Engine Protection
71 Diagnostic Codes Output Signal Stuck High (generated by code reader)
72 Diagnostic Codes Output Signal Stuck Low (generated by code reader)
73 Fuel Flow/Throttle Output Signal Stuck High (generated by code reader)
74 Fuel Flow/Throttle Output Signal Stuck Low (generated by code reader)
75 Open in Rack Actuator Circuit
76 Rack Actuator Circuit Grounded
81 Fuel Temperature Above Warning Threshold
85 Speed Sensor Input is Open
86 Speed Sensor Input Voltage is To Low
87 Speed Sensor Input Voltage is To High

 

OUO1078,0000442 -19-23MAY05-2/2