NO.8 ABNORMAL SHIFTING (SHIFT PATTERN DIFFERS FROM NORMAL) [DJVA-EL]

id050312955100

8

Abnormal shifting (Shift pattern differs from normal)
DESCRIPTION
•  Shift pattern differs from normal shift pattern.
POSSIBLE CAUSE
When inspecting for abnormal shifting, it is important to determine if there is a malfunction in the electric system or CVT.
•  APP sensor malfunction
―  The output voltage from the APP sensor is important for shift changes. Therefore, shifting may not occur even when the accelerator pedal is depressed if this sensor does not output the correct voltage corresponding to the accelerator position.
―  Abnormal shifting is indicated if the APP sensor output voltage changes automatically even though the accelerator pedal depression amount is maintained.
•  Clutch slippage, burnt
•  Control valve body malfunction (Improper operation, stuck, restrict oil line)
•  CVT internal malfunction
•  Input sensor malfunction
•  Selector cable misadjustment
Note
•  Before following the symptom troubleshooting steps, make sure that the Automatic Transaxle On-Board Diagnostic and Automatic Transaxle Basic Inspection are conducted. (See ON-BOARD DIAGNOSTIC SYSTEM DTC INSPECTION [DJVA-EL].) (See BASIC INSPECTION [DJVA-EL].)

Diagnostic procedure

STEP

INSPECTION

ACTION
1
Are the selector lever position and selector cable adjustment properly?
Yes
Go to the next step.
No
Adjust the selector cable.
(See CVT (CONTINUOUSLY VARIABLE TRANSAXLE) SHIFT MECHANISM REMOVAL/INSTALLATION.)
2
Inspect the following TCM PIDs values using the M-MDS:
(See ON-BOARD DIAGNOSTIC SYSTEM PID/DATA MONITOR INSPECTION [DJVA-EL].)
•  SLT (Belt grip pressure linear solenoid)
•  SL (Torque converter clutch (TCC) solenoid)
•  DSU (Torque converter clutch (TCC) engage solenoid)
•  DS1 (Shift control solenoid No.1)
•  DS2 (Shift control solenoid No.2)
Does each PID monitoring value change simultaneously with the abnormal shifting?
Yes
If the signal to each solenoid changes simultaneously with the abnormal shifting, there is a malfunction in the electrical system.
•  Go to the next step.
No
CVT internal malfunction.
•  Clutch slippage
•  Control valve body malfunction
Replace the CVT.
(See CVT (CONTINUOUSLY VARIABLE TRANSAXLE) REMOVAL/INSTALLATION [DJVA-EL].)
3
Access the following PCM PIDs using the M-MDS:
(See ON-BOARD DIAGNOSTIC TEST [MZR 1.5, MZR 1.6].)
•  APP
•  VSS
Are all PID values normal?
(See PCM INSPECTION [MZR 1.5, MZR 1.6].)
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
4
Disconnect the TCM connector.
Measure the resistance between ground terminal at the TCM connector (terminal A1 and A23) and body ground.
Is the resistance less than 5.0 ohms?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit.
5
Inspect the input signal circuit between following sensors and TCM:
•  Oil pressure sensor
•  Transaxle fluid temperature (TFT) sensor
•  Input/turbine speed sensor
•  Primary pulley speed sensor
•  Secondary pulley speed sensor
•  TR switch
•  Grade sensor
Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
6
Inspect the following sensors:
•  Oil pressure sensor
•  Transaxle fluid temperature (TFT) sensor
•  Input/turbine speed sensor
•  Primary pulley speed sensor
•  Secondary pulley speed sensor
•  TR switch
•  Grade sensor
Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
•  If the transaxle fluid temperature (TFT) sensor has a malfunction:
―  Replace the CVT.
No
Replace the TCM.
(See TCM REMOVAL/INSTALLATION [DJVA-EL].)
7
•  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, the symptom troubleshooting is completed.
•  If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM. (See TCM REMOVAL/INSTALLATION [DJVA-EL].)