NO.15 SHIFT CONCERN: NO 3–4 SHIFT[LA4AX-EL (CD4E)]

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15

Shift concern: no 3–4 shift

POSSIBLE CAUSE

•  Powertrain control system malfunction

•  Improper pressure

•  Control valve body malfunction

•  2/4 band and servo component malfunction

•  Coasting clutch component malfunction

•  Forward OWC component malfunction

•  Transaxle case malfunction

15	Shift concern: no 3–4 shift
POSSIBLE CAUSE	• Powertrain control system malfunction • Improper pressure • Control valve body malfunction • 2/4 band and servo component malfunction • Coasting clutch component malfunction • Forward OWC component malfunction • Transaxle case malfunction

Diagnostic procedure

STEP	INSPECTION		ACTION
1	Powertrain control system • Do any of the following malfunctions exist? ― Electrical input/output ― Vehicle wiring harness ― PCM ― Shift solenoid No.1 (SS1), Shift solenoid No.2 (SS2) ― Transaxle range (TR) switch	Yes	Perform OBD test Perform DTC troubleshooting (See AUTOMATIC TRANSAXLE ON-BOARD DIAGNOSTIC FUNCTION[LA4AX-EL (CD4E)].)
1		No	Go to the next step
2	Improper pressure • Do any of the following malfunctions exist? ― High line pressure ― Low line pressure (See MECHANICAL SYSTEM TEST[LA4AX-EL (CD4E)].)	Yes	Go to the next step
2		No	Go to step 4
3	Control valve body • Do any of the following malfunctions exist? ― Bolts are not tightened to the specification ― Gasket leaks ― 3-4 Shift Valve, main regulator valve are stuck, damaged, or misassembled ― SS1, SS2 malfunction (Also no first gear) ― Separator plates are damaged, or orifice is blocked	Yes	Service if necessary
3		No	Go to the next step
4	2/4 band and servo component (No second gear engagement also) • Do any of the following malfunctions exist? ― 2/4 band is damaged or worn ― Servo rod or rod bore is damaged ― Servo piston or cover is damaged or leaking ― Springs are damaged	Yes	Service if necessary
4		No	Go to the next step
5	Coasting clutch component • Do any of the following malfunctions exist? ― Seals are damaged or missing ― Piston is damaged ― Friction is severely damaged or worn ― Check ball is severely damaged	Yes	Service if necessary
5		No	Go to the next step
6	Forward OWC component • Is there any damage?	Yes	Service if necessary
6	Forward OWC component • Is there any damage?	No	Go to the next step
7	Transaxle case (No second gear engagement also) • Do any of the following problems exist? ― Band anchor is damaged ― Leakage in the servo apply and servo release	Yes	Service if necessary
7		No	Go to the next step
8	• 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.