Mitsubishi L200. Manual - part 284
TROUBLESHOOTING
AUTOMATIC TRANSMISSION
23A-43
DIAGNOSIS CODE SET CONDITIONS
If the output pulse from the output shaft speed sen-
sor has been lost for one second or more while the
vehicle is being driven, it is judged that there is an
open circuit or short circuit in the output shaft speed
sensor, and diagnosis code No.P1767 (P0720) is
set.
If the code No.P1767 (P0720) is set four times, the
transmission will be fixed in 3rd gear as a fail-safe
measure. However, the transmission can be down-
shifted to 2nd gear by operating the selector lever.
PROBABLE CAUSES
• Malfunction of output shaft speed sensor
• Malfunction of output shaft <4A/T>
• Malfunction of direct planetary carrier <5A/T>
• Damaged harness wires and connectors
• Malfunction of the A/T-ECU
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III data list
Item 06: Output shaft speed sensor (Refer to data list
reference table
Q: Is the check result normal?
YES :
Intermittent malfunction (Refer to GROUP
00
− How to Cope with Intermittent
Malfunction ).
NO :
Go to Step 2.
STEP 2. Connector check: B-16 output shaft
speed sensor connector
Check for the contact with terminals.
Q: Is the check result normal?
YES :
Go to Step 3.
NO :
Repair the defective connector.
STEP 3. Measure the resistance at output shaft
speed sensor connector B-16.
Disconnect the connector, and measure the resist-
ance between terminal 1 and earth at the wiring har-
ness side.
OK: Continuity (Less than 2
Ω)
Q: Is the check result normal?
YES :
Go to Step 9.
NO :
Go to Step 4.
STEP 4. Measure the voltage at A/T-ECU
connector C-12.
(1) Connect output shaft speed sensor connector B-
16.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between A/T-ECU
connector C-12 terminal No.43 and earth.
OK: 0.5 V or less
Q: Is the check result normal?
YES :
Go to Step 7.
NO :
Go to Step 5.
STEP 5. Connector check: C-12 A/T-ECU
connector
Check for the contact with terminals.
Q: Is the check result normal?
YES :
Go to Step 6.
NO :
Repair the defective connector.
STEP 6. M.U.T.-III data list
Item 06: Output shaft speed sensor (Refer to data list
reference table
Q: Is the check result normal?
YES :
Intermittent malfunction (Refer to GROUP
00
− How to Cope with Intermittent
Malfunction ).
NO :
Replace the A/T-ECU.
STEP 7. Connector check: B-11 intermediate
connector, C-12 A/T-ECU connector
Check for the contact with terminals.
Q: Is the check result normal?
YES :
Go to Step 8.
NO :
Repair the defective connector.
STEP 8. Check the harness between output shaft
speed sensor connector B-16 terminal No.1 and
A/T-ECU connector C-12 terminal No.43.
Check the earth line for open circuit.
Q: Is the check result normal?
YES :
Go to Step 6.
NO :
Repair the wiring harness.
STEP 9. Measure the voltage at output shaft
speed sensor connector B-16.
(1) Disconnect the connector, and measure the
voltage between terminal 3 and earth at the
wiring harness side.
(2) Turn the ignition switch to the ON position.
OK: System voltage
Q: Is the check result normal?
YES :
Go to Step 12.
NO :
Go to Step 10.