FUEL SYSTEM <4D5-step
III
> -
Troubleshooting
13-26
Code No. 51 EGR valve position sensor system
Probable cause
Range of Check
D
Ignition switch: ON, except during engine cranking
Set Condition
D
Output voltage of EGR valve position sensor for 3 seconds is 4.85 V or
higher, or lower than 0.15 V
D
EGR valve position sensor inoperative
D
EGR valve position sensor open circuit, short
circuit or connector circuit inoperative
D
Engine-ECU inoperative
Repair
NG
NG
OK
Check the harness between the engine-ECU
and the EGR valve position sensor
connector.
Replace the engine-ECU.
Repair
NG
OK
NG
Repair
OK
OK
Check the harness between the
engine-ECU and the EGR valve position
sensor connector.
EGR valve position sensor check
(Refer to P.13-61.)
OK
Replace
Check the following connector:
C-43
Check the trouble symptoms.
NG
NG
Check the following connector:
A-135
NG
Repair
OK
Check the trouble symptoms.
NG
NG
Measure at C-43 engine-ECU connector
D
Connect the connector.
D
Voltage between 90 and earth.
OK:
0.4 - 0.6 V
(Ignition switch: ON)
4.1 - 4.8 V
(When 60 kPa of negative pressure is
applied to the EGR valve nipple and the
valve is fully open)
OK
Measure at A-135 EGR valve position sensor
connector.
D
Disconnect the connector and measure at
the harness side.
D
Voltage between 2 and earth
(Ignition switch: ON)
OK:
4.5 - 5.5 V
D
Continuity between 3 and earth
OK:
Continuity
Replace the engine-ECU.
Replace the engine-ECU.
Check the following connector:
C-130
NG
Repair
OK
Check the trouble symptoms.
NG