DTC P0731: 1st Gear Incorrect Ratio: Diagnosis
WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.
- STEP 1. Check the DTC.
Check that P0715 (input shaft speed sensor) and P0720 (output shaft speed sensor) are set.
Q: Is the DTC stored?
- YES: Check and repair the relevant DTC system.
- NO: Go to Step 2.
- STEP 2. Check the DTC.
Check if the DTC other than P0731 (1st gear ratio) is stored.
Q: Is the DTC stored?
- YES: Check and repair the relevant DTC system.
- NO: Go to Step 3.
- STEP 3. Check the transmission fluid properties.
Check the status of the transmission fluid properties (smell, color, fouling).
- Black: A/T inside damage, seizure
- Milky: Water intrusion
Q: Is the check result normal?
- YES: Go to Step 4.
- NO: Remove the A/T from the vehicle, then check and repair the inside.
- STEP 4. Check the transmission fluid level.
Q: Is the check result normal?
- YES: Go to Step 5.
- NO: Adjust the transmission fluid level, and then go to Step 5.
- STEP 5. Check the signals of input shaft speed sensor and output shaft speed sensor.
Check the signals of TCM connector PGA1, PGB1 terminal.
Refer to CHECK AT ENGINE TCM TERMINAL .
Q: Is the check result normal?
- YES: Go to Step 6.
- NO: Repair or replace the failure section.
- STEP 6. Hydraulic pressure test
Refer to HYDRAULIC PRESSURE TESTS .
Q: Is the check result normal?
- YES: Go to Step 7.
- NO: Remove the A/T from the vehicle, then check and repair the inside.
- STEP 7. Erase the DTC, and drive the vehicle for a while.
Check that the normal code is displayed.
Q: Is the check result normal?
- YES: The procedure is complete.
- NO: Return to Step 1.