NO.3 HARSH ENGAGEMENT [LA4AX-EL (CD4E)]

id0503a2806600

3

Harsh engagement

POSSIBLE CAUSE

• ATF
• Powertrain control system malfunction
• Improper pressure
• Control valve body malfunction
• Oil filter and seal malfunction
• Internal and external linkage malfunction
• Joint shafts malfunction
• Engine mount malfunction
• Forward clutch component (Forward only) malfunction
• Reverse clutch component (Reverse only) malfunction
• Low/reverse clutch component (Reverse only) malfunction
• Direct clutch component (Reverse only) malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
ATF
• Are there any problems with the following?
- Level
- Condition
(See AUTOMATIC TRANSAXLE FLUID (ATF) INSPECTION [LA4AX-EL (CD4E)].)
Yes
Service if necessary
No
Go to the next step
2
Powertrain control system
• Are there any malfunctions with the following?
- Electrical input/output
- Vehicle wiring harness
- PCM
- Electrical pressure control (EPC) solenoid
- Transaxle fluid temperature (TFT) sensor
- 3-2 timing/coasting clutch solenoid (3-2 T/CCS) (Harsh forward only)
Yes
Run OBD test
Perform DTC troubleshooting
No
Go to the next step
3
Improper pressure
• Is the line pressure higher than normal?
Yes
Verify engagements at minimum EPC using the transaxle tester
If the line pressure remains high, inspect the following components: control valve body, oil filter, and seal component
No
Go to the next step
4
Control valve body
• Do any of the following malfunctions exist?
- Bolts are not tightened to the specification
- Gaskets are damaged
- Low/reverse accumulator piston and spring (Reverse), main regulator valve, coast clutch valve (Forward) are damaged, missing, stuck, or misassembled
- Accumulator piston and spring are misassembled, stuck, or damaged
- EPC solenoid is stuck, or damaged
Yes
Service if necessary
No
Go to the next step
5
Oil Filter and seal component
• Do any of the following malfunctions exist?
- Filter/seal is damaged or plugged
- Recirculation seal is damaged, plugged, or out of position
Yes
Replace if necessary
No
Go to the next step
6
Internal or external shift linkages
• Do any of the following malfunctions exist?
- Damage
- Misadjustment
(See SELECTOR LEVER REMOVAL/INSTALLATION.)
Yes
Service if necessary
No
Go to the next step
7
Joint shafts
• Is there spline damage?
Yes
Service if necessary
No
Go to the next step
8
Engine mounts
• Do any of the following malfunctions exist?
- Loose, broken, missing, or misaligned parts
- Powertrain is contacting with other vehicle components
(See AUTOMATIC TRANSAXLE REMOVAL [LA4AX-EL (CD4E)].)
(See AUTOMATIC TRANSAXLE INSTALLATION [LA4AX-EL (CD4E)].)
Yes
Service if necessary
No
Go to the next step
9
F/C/D clutch component (Forward only)
• Do any of the following malfunctions exist?
- Forward/coasting/direct (F/C/D) clutch cylinders are damaged
- Piston bore is damaged
- Friction elements are damaged or worn
- Forward clutch return spring is damaged or missing
- Inspect the ball for damage
- Piston or seals are damaged
Yes
Service if necessary
No
Go to the next step
10
Reverse clutch component (Reverse only)
• Do any of the following malfunctions exist?
- Seals or piston are damaged
- Reverse piston is damaged
- Friction elements are damaged, worn, or misassembled
- Return spring component is damaged or worn
- Ball check valve is damaged or missing
Yes
Service if necessary
No
Go to the next step
11
Low/reverse clutch component (Reverse only)
• Do any of the following malfunctions exist?
- Seals or piston are damaged
- Wave spring is damaged
- Friction elements are damaged, worn, misassembled
- Return spring component is damaged, worn, or misassembled
- Piston bore is damaged
Yes
Service if necessary
No
Go to the next step
12
Direct clutch component (Reverse only)
• Are any of the friction elements severely damaged?
Yes
Service if necessary
No
The problem is resolved
13
• Verify the test results.
- If normal, return to the diagnostic index to service any additional symptoms.
- If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair 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.