FAILURE DIAGNOSIS
TNV DI Service Manual
1-151
Method and Procedure of Failure Diagnosis
3. Check of harness continuity:
•
Remove the accelerator sensor and E-ECU from the harness.
•
Check the harness continuity using a circuit tester.
4. Check of the sensor output voltage:
•
Connect the 2G eco-checker harness between E-ECU and machine’s harness (for details, see [How to
use the 2G eco-checker harness] (P.1-135). And connect the all connectors (sensors, E-ECU).
•
Measure the voltage between sensor signal E37 and E28 using a circuit tester.
Terminal
Continuity
Status
Sensor signal wire E37
[Between E-ECU and sensor connector]
Available
OK: normal
Unavailable
NG: harness disconnection
Sensor GND wire E28
[Between E-ECU and sensor connector]
Available
OK: normal
Unavailable
NG: harness disconnection
Sensor 5V wire E38
[Between E-ECU and sensor connector]
Available
OK: normal
Unavailable
NG: harness disconnection
Between E37 and other terminal/GND,
and between E38 and other
terminal/GND
Unavailable
OK: normal
Available
NG: harness short-circuited with GND
Between E28 and GND/E45/E47
Available
OK: normal
Unavailable
NG: harness disconnection
Between E28 and other terminals
Unavailable
OK: normal
Available
NG: harness short-circuited with another
wiring
NG
• Check if the harness is damaged, or if the wiring is correct.
• Replace the harness.
OK
Check the output voltage of the spare accelerator sensor or the atmospheric
pressure sensor.
→
Go to [4. Check of the sensor output voltage:]
Voltage
Status
Action
E37
≤
0.2[V]
NG
• Replace the harness.
• Replace the sensor.
0.2[V] < E37 < 4.6[V]
OK
(normal range)
Replace the E-ECU.
4.6V
≤
E37
NG
• Replace the harness.
• Replace the sensor.
NG
• Check if the harness is damaged, or if the wiring is correct.
• Replace the harness.
OK
Replace the E-ECU.
TNV_DI_SM_A4-Troubleshooting.book 151 ページ 2007年11月15日 木曜日 午後5時27分