
REAR AXLE –
Troubleshooting <AYC>
27-16
Code No. 73: Directional control valve (left) system
Probable cause
This code is output when the directional control valve (left) control circuit is open-
or short-circuited.
D
Defective directional control valve (left)
D
Defective harness or connector
D
Defective AYC-ECU
NG
Check and repair the harness between
directional control valve (left) and body
ground.
OK
Check the trouble symptom.
OK
Replace AYC-ECU.
NG
Check the harness between directional
control valve (left) and AYC-ECU.
NG
Repair
OK
Check the trouble symptom.
OK
Check the following connectors:
B-96, B-94, D-06, F-30, F-28
NG
Repair
OK
Measure at F-28 directional control
valve (left) connector.
D
Disconnect the connector and
measure at the directional control
valve side.
D
Continuity across 1 and body
ground
OK: Conducting
NG
Check the following connectors:
F-28, F-30
NG
Repair
Measure at F-28 directional control
valve (left) connector.
D
Disconnect the connector and
measure at the directional control
valve side.
D
Resistance across 1 – 2
OK: 19 – 21
Ω
or less
NG
Replace the hydraulic unit.