FAILURE DIAGNOSIS
1-150
TNV DI Service Manual
Method and Procedure of Failure Diagnosis
Work Description
1. Check of the sensor resistance value (sensor only):
• Between sensor terminal A and C of the spare accelerator sensor or the atmospheric pressure sensor
(total resistance value)
•
Remove the harness from the spare accelerator sensor or the atmospheric pressure sensor.
•
Measure the resistance between sensor terminals A and C (total resistance value) using a circuit tester.
(REF) Total resistance value of Yanmar standard spare accelerator sensor or atmospheric pressure sensor
• Between sensor terminal A and B of the spare accelerator sensor or the atmospheric pressure sensor
•
Measure the resistance between sensor terminals A and B using a circuit tester.
•
Check if the resistance value between sensor terminal A and B fluctuates when the sensor opening is
changed.
2. Check of the sensor resistance value ( harness):
• Between harness E38 and E28 (all the resistance value)
•
Connect sensor and harness, and remove E-ECU from the harness.
•
Measure the resistance between harness side E-ECU connectors E38 and E28 (all the resistance value)
using a circuit tester. *Refer to above-mentioned sensor resistance values.
• Between harness E37 and E28
•
Measure the resistance between E-ECU connectors E37 and E28 using a circuit tester.
•
Check if the resistance value between E-ECU connector E37 and E28 fluctuates when the sensor
opening is changed.
Terminal
Specification
Sensors A - C
5 ± 1.5k
Ω
NG
Replace the spare accelerator sensor or the atmospheric pressure sensor.
OK
Check the resistance value between terminal A and B of the spare accelerator
sensor or the atmospheric pressure sensor.
→
Go to [• Between sensor terminal A
and B of the spare accelerator sensor or the atmospheric pressure sensor]
NG
Replace the spare accelerator sensor or the atmospheric pressure sensor.
OK
Check the sensor resistance with the sensor and the harness being connected.
→
Go to [2. Check of the sensor resistance value ( harness):]
NG
Check the harness for correct continuity.
→
Go to [3. Check of harness continuity:]
OK
Check the resistance value between the harness E37 and E28.
→
Go to [• Between
harness E37 and E28]
NG
Check the harness for correct continuity.
→
Go to [3. Check of harness continuity:]
OK
Check the sensor resistance with the sensor and the harness being connected.
→
Go to [2. Check of the sensor resistance value ( harness):]
TNV_DI_SM_A4-Troubleshooting.book 150 ページ 2007年11月15日 木曜日 午後5時27分