Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostic Procedure
- CHECK STEP MOTOR FUNCTION
Perform the self-diagnosis check. Refer to "SELF-DIAGNOSTIC RESULT MODE ".
Is a malfunction in the step motor function indicated in the results?
YES: Repair or replace damaged parts. (Check the step motor function. Refer to "DTC P1778 STEP MOTOR - FUNCTION ".)
NO: GO TO 2.
- CHECK OUTPUT SPEED SENSOR (SECONDARY SPEED SENSOR SYSTEM) AND INPUT SPEED SENSOR (PRIMARY SPEED SENSOR) SYSTEM
Check output speed sensor (secondary speed sensor) system and input speed sensor (primary speed sensor) system. Refer to "DTC P0720 VEHICLE SPEED SENSOR CVT (SECONDARY SPEED SENSOR) ", "DTC P0715 INPUT SPEED SENSOR CIRCUIT (PRI SPEED SENSOR) ".
OK or NG
OK: GO TO 3.
NG: Repair or replace damaged parts.
- CHECK ENGINE SPEED SIGNAL SYSTEM
Check engine speed signal system. Refer to "DTC P0725 ENGINE SPEED SIGNAL ".
OK or NG
OK: GO TO 4.
NG: Repair or replace damaged parts. Refer to "IGNITION SIGNAL ".
- DETECT MALFUNCTIONING ITEM
Check the following:
- Power supply and ground circuit for TCM. Refer to "DTC P1701 TRANSMISSION CONTROL MODULE (POWER SUPPLY) ".
- The TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK: GO TO 5.
NG: Repair or replace damaged parts.
- CHECK DTC
Perform "DTC CONFIRMATION PROCEDURE ".
OK or NG
OK: INSPECTION END
NG: Replace TCM or transaxle assembly. Refer to "SERVICE AFTER REPLACING TCM AND TRANSAXLE ASSEMBLY ", "REMOVAL AND INSTALLATION (MR20DE) ".
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.