NO.9 ABNORMAL SHIFTING [GF4AX-EL]


9	Abnormal shifting
DESCRIPTION	• Shift incorrectly (incorrect shift pattern).
POSSIBLE CAUSE	• There is a malfunction in the signal circuit which controls shifting (TP sensor, input/turbine speed sensor, VSS); the control valve is stuck, or the clutch circuit is stuck. 1. Clutch slippage, burnt • Line pressure low • TP sensor malfunction or mis-adjustment • VSS malfunction • Input/turbine speed sensor malfunction • Sensor GND malfunction • Shift solenoid A, B, or C malfunction • TCC solenoid valve malfunction • Body GND malfunction • Accelerator cable mis-adjustment • Control valve body malfunction Note • Before following the troubleshooting steps, make sure that the Automatic Transaxle On-Board Diagnostic and Automatic Transaxle Basic Inspection are conducted.


STEP	INSPECTION		ACTION
1	Inspect for continuity between the PCM terminals 4, 5, 14, 54 or 80 and the transaxle case. Is there continuity?	Yes	Go to the next step.
1		No	Repair or replace GND circuit.
2	Connect the WDS or equivalent to DLC-2. Access TRD, TRL, TRS, TP, TSS and VSS PIDs. Drive the vehicle in D, 2, and 1 ranges while monitoring PIDs (O/D OFF switch off). (See PCM INSPECTION [L3 R.H.D.].) Are the PIDs within the specification?	Yes	Go to the next step.
2		No	TRD, TRL or TRS PID: • Inspect the TR switch and related wiring harness: for intermittent open/short circuit during vibration. TP PID: • Inspect if output signal from the TP sensor for smooth changes. TSS PID: • Inspect the input/turbine speed sensor and related wiring harness: for intermittent open/short circuit during vibration. VSS PID: • Inspect for intermittent open circuit of the VSS and related wiring harness.
3	Stop the engine and turn the ignition switch to the ON position. Connect the WDS or equivalent to DLC-2. Simulate SSA/SS1, SSB/SS2 and SSC/SS3 PIDs for ON. Is operating sound of the shift solenoids heard?	Yes	Inspect the PCM connector terminal for bent terminal, damage, corrosion or poor contact.
3		No	Inspect connection of the shift solenoid A, B, or C terminal on the ATX for bend, damage, corrosion or looseness. Inspect for stuck shift solenoid? (See Operating Inspection (On-vehicle Inspection).) If the shift solenoids are normal, inspect for open or short circuit between the PCM terminals 92, 66 or 40 and the coupler component terminals A, B, or C.
4	• Verify the test results. - If normal, return to the diagnostic index to service any additional symptoms. - If the malfunction remains, inspect the related Service Information and perform repair or diagnosis. • If the vehicle is repaired, troubleshooting is completed. • If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM.