Electronic Controlled Automatic Transaxle (ECT) - Diagnosis: Overview Lexus RX II

MONITOR DESCRIPTION

The park/neutral position switch detects the gearshift position and sends a signal to the ECM.

For security, the park/neutral position switch detects the gearshift position so that engine can be started only when the vehicle is in P or N shift position.

When the park/neutral position switch sends more than one signal at a time from switch positions P, R, N, D, 3 *1 or 2 *1 , the ECM interprets this as a fault in the switch. The ECM will turn on the MIL.

HINT

*1: Gate shift lever type

*2: Shift lever with Multi-mode automatic transmission type

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(B) *2

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1. INSPECT PARK/NEUTRAL POSITION SWITCH ASSY Disconnect the park/neutral position switch connector. Gate shift lever type: Measure resistance according to the value(s) in the table below when the shift lever is moved to each position. Standard: Shift lever with Multi-mode automatic transmission type: Measure resistance according to the value(s) in the table below when the shift lever is moved to each position. Standard: OK: GO TO NEXT STEP. NG: REPLACE PARK/NEUTRAL POSITION SWITCH ASSY (See «REPLACEMENT»(ref-209590-S33062210732005121000000) )
2. INSPECT SHIFT LOCK CONTROL UNIT ASSY Connect the park/neutral position switch connector. Disconnect the transmission control switch connector or shift lock control unit assy. Gate shift lever type: Measure resistance according to the value(s) in the table below when the shift lever is moved to each position. Standard: Shift lever with Multi-mode automatic transmission type: Measure resistance according to the value(s) in the table below when the shift lever is moved to each position. Standard: OK: GO TO NEXT STEP. NG: REPLACE SHIFT LOCK CONTROL UNIT ASSY (See «SHIFT LEVER ASSY (ATM)»(ref-209590-S14774750982005121000000) )
3. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - ECM) Connect the transmission control switch connector of shift lock control unit assy. Gate shift lever type: Turn the ignition switch to the ON position, and measure the voltage according to the value(s) in the table below when the shift lever is moved to each position. Standard: HINT: *: The voltage will drop slightly due to lighting up of the back up light. Shift lever with Multi-mode automatic transmission type: Turn the ignition switch to the ON position, and measure the voltage according to the value(s) in the table be when the shift lever is moved to each position. Standard: HINT: *: The voltage will drop slightly due to lighting up of the back up light. OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )

The automatic transmission fluid (ATF) temperature sensor converts ATF temperature to an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature, and the ECM detects an opens or shorts in the ATF temperature circuit. If the resistance value of the ATF temperature is less than 79 ohm or more than 156 k/ohm, the ECM interprets this as a fault in the ATF sensor or wiring. The ECM will turn on the MIL.

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1. INSPECT TRANSMISSION WIRE (ATF TEMPERATURE SENSOR) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: GO TO NEXT STEP. NG: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) )
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission wire connector to the transaxle. Disconnect the ECM connectors. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )

The ATF temperature sensor converts the ATF temperature to an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature and detects an opens or shorts in the ATF temperature circuit.

After running the vehicle for a certain period, the ATF temperature should increase. When the ATF temperature is below 10°C, the ECM interprets this as a fault, turns on the MIL.

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1. INSPECT TRANSMISSION WIRE (ATF TEMPERATURE SENSOR) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: GO TO NEXT STEP. NG: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) )
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission wire connector to the transaxle. Disconnect the ECM connectors. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. OK: Standard (Check for short): NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) ) OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM )

The NT terminal of the ECM detects the input turbine speed sensor's revolving signal (input RPM). The ECM outputs a gearshift signal comparing the input turbine speed sensor (NT) with the counter gear speed sensor (NC).

When the ECM detects this code abnormally, the ECM performs the fail-safe and outputs a gearshift signal based on the signal from the counter gear speed sensor (NC).

While the vehicle is operating in the 2nd, 3rd, 4th or 5th gear position in the shift position of D, if the input shaft revolution is less than 300 RPM although the output shaft revolution is more than 1,000 RPM, the ECM detects the trouble.

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1. INSPECT SPEED SENSOR (NT) Disconnect the speed sensor connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: TOYOTA made: Standard: AISIN made: OK: GO TO NEXT STEP. NG: REPLACE SPEED SENSOR (NT)
2. CHECK HARNESS AND CONNECTOR (SPEED SENSOR - ECM) Connect the speed sensor connector. Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. Standard: TOYOTA made: Standard: AISIN made: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )

The circuit prevents the engine from stopping when the vehicle is stopped by sudden braking when the torque converter clutch is in the "lock-up" mode. The ECM receives the signal from the stop light switch at the time brake pedal is depressed. Then, the ECM sends the signal to the lock-up solenoid valve not to be in lock-up condition. When the stop light switch remains ON during "stop and go" driving, the ECM interprets this as a fault in the stop light switch and the MIL comes on. The vehicle must stop and go (3 km/h (2 mph) to 30 km/h (19 mph)) ten times for two driving cycles in order to detect malfunction.

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SYSTEM DESCRIPTION

The ECM uses the signals from the throttle position sensor, air flow meter, turbine (input) speed sensor, intermediate (counter) shaft speed sensor and crankshaft position sensor to monitor the engagement condition of the lock-up clutch.

Then the ECM compares the engagement condition of the lock-up clutch with the lock-up schedule in the ECM memory to detect a mechanical problems of the shift solenoid valve DSL, valve body and torque converter clutch.

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Torque converter lock-up is controlled by the ECM based on input turbine RPM (NT), counter gear RPM (NC), engine RPM, engine load, engine temperature, vehicle speed, transmission temperature, and gear selection. The ECM determines the lock-up status of the torque converter by comparing the engine RPM (NE) to the input turbine RPM (NT). The ECM calculates the actual transmission gear by comparing input turbine RPM (NT) to counter gear RPM (NC). When conditions are appropriate, the ECM requests "lock-up" by applying control voltage to shift solenoid DSL. When opened, solenoid DSL applies pressure to the lock-up relay valve and locks the torque converter clutch. If the ECM detects no lock-up after lock-up has been requested or if it detects lock-up when it is not requested, the ECM interprets this as a fault in the torque converter clutch performance. The ECM will turn on the MIL.

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The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves and valve body.

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The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual gear position (1st, 2nd, 3rd, 4th or 5th gear position). When the gear position commanded by the ECM and the actual gear position are not same, the ECM illuminates the MIL.

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OFF malfunction

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ON malfunction (A)

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ON malfunction (B)

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1. INSPECT SHIFT SOLENOID VALVE (SL1) Remove the shift solenoid valve SL1. Measure the resistance according to the value(s) in the table below. Standard: Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve. Standard: The solenoid makes an operating noise. OK: GO TO NEXT STEP. NG: REPLACE SHIFT SOLENOID VALVE (SL1)
2. INSPECT TRANSMISSION VALVE BODY ASSY (See chapter 2 in «PROBLEM SYMPTOMS TABLE»(ref-209546-S11825380642005121000000) ) OK: GO TO NEXT STEP. NG: REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSY (See «REPLACEMENT»(ref-209590-S05223735902005121000000) )
3. INSPECT TORQUE CONVERTER CLUTCH ASSY (See «TORQUE CONVERTER CLUTCH AND DRIVE PLATE (ATM)»(ref-209590-S35507545572005121000000) ) OK: REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSY (See «AUTOMATIC TRANSAXLE ASSY (U151E/U151F)»(ref-209590-S25711046832005121000000) ) NG: REPLACE TORQUE CONVERTER CLUTCH ASSY

The ECM commands gearshift by turning the shift solenoid valves "ON/OFF". When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem and the MIL comes on. Illuminating the MIL, the ECM performs the fail-safe and turns the other shift solenoid valves in good condition "ON/OFF" (In case of an open or short circuit, the ECM stops sending current to the circuit).

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1. INSPECT TRANSMISSION WIRE (SL1) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: GO TO NEXT STEP. NG: Go to step 3
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission connector to the transaxle. Disconnect the connector from the ECM. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )
3. INSPECT SHIFT SOLENOID VALVE (SL1) Remove the shift solenoid valve SL1. Measure the resistance according to the value(s) in the table below. Standard: Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve. Standard: The solenoid makes an operating noise. OK: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) ) NG: REPLACE SHIFT SOLENOID VALVE (SL1)

The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves and valve body.

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The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual gear position (1st, 2nd, 3rd, 4th or 5th gear position). When the gear position commanded by the ECM and the actual gear position are not same, the ECM illuminates the MIL.

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OFF malfunction (A)

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OFF malfunction (B)

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ON malfunction (A)

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ON malfunction (B)

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1. INSPECT SHIFT SOLENOID VALVE (S4) Remove the shift solenoid valve S4. Measure the resistance according to the value(s) in the table below. Standard: Connect positive (+) lead to the terminal of solenoid connector, negative (-) lead to the solenoid body. Standard: The solenoid makes an operating noise. OK: GO TO NEXT STEP. NG: REPLACE SHIFT SOLENOID VALVE (S4)
2. INSPECT TRANSMISSION VALVE BODY ASSY (See chapter 2 in «PROBLEM SYMPTOMS TABLE»(ref-209546-S11825380642005121000000) ) OK: GO TO NEXT STEP. NG: REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSY (See «TRANSMISSION VALVE BODY ASSY (U151E/U151F)»(ref-209590-S36275406272005121000000) )
3. INSPECT TORQUE CONVERTER CLUTCH ASSY (See «TORQUE CONVERTER CLUTCH AND DRIVE PLATE (ATM)»(ref-209590-S35507545572005121000000) ) OK: REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSY (See «AUTOMATIC TRANSAXLE ASSY (U151E/U151F)»(ref-209590-S25711046832005121000000) ) NG: REPLACE TORQUE CONVERTER CLUTCH ASSY

The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves and valve body.

Scheme 123

The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual gear position (1st, 2nd, 3rd, 4th or 5th gear position). When the gear position commanded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL.

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ALL

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OFF malfunction (A)

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OFF malfunction (B)

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ON malfunction (A)

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ON malfunction (B)

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ON malfunction (C)

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ON malfunction (D)

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1. INSPECT SHIFT SOLENOID VALVE (SR) Remove the shift solenoid valve SR. Measure the resistance according to the value(s) in the table below. Standard: Connect positive (+) lead to the terminal of solenoid connector, negative (-) lead to the solenoid body. Standard: The solenoid makes an operating noise. OK: GO TO NEXT STEP. NG: REPLACE SHIFT SOLENOID VALVE (SR)
2. INSPECT TRANSMISSION VALVE BODY ASSY (See chapter 2 in «PROBLEM SYMPTOMS TABLE»(ref-209546-S11825380642005121000000) ) OK: GO TO NEXT STEP. NG: REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSY (See «TRANSMISSION VALVE BODY ASSY (U151E/U151F)»(ref-209590-S36275406272005121000000) )
3. INSPECT TORQUE CONVERTER CLUTCH ASSY (See «TORQUE CONVERTER CLUTCH AND DRIVE PLATE (ATM)»(ref-209590-S35507545572005121000000) ) OK: REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSY (See «AUTOMATIC TRANSAXLE ASSY (U151E/U151F)»(ref-209590-S25711046832005121000000) ) NG: REPLACE TORQUE CONVERTER CLUTCH ASSY

The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves and valve body.

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The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual gear position (1st, 2nd, 3rd, 4th or 5th gear position). When the gear position commanded by the ECM and the actual gear position are not same, the ECM illuminates the MIL.

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ALL

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OFF malfunction (A)

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OFF malfunction (B)

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OFF malfunction (C)

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OFF malfunction (D)

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ON malfunction (A)

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ON malfunction (B)

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ON malfunction (C)

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1. INSPECT SHIFT SOLENOID VALVE (SL2) Remove the shift solenoid valve SL2. Measure the resistance according to the value(s) in the table below. Standard: Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve. Standard: The solenoid makes an operating noise. OK: GO TO NEXT STEP. NG: REPLACE SHIFT SOLENOID VALVE (SL2)
2. INSPECT TRANSMISSION VALVE BODY ASSY (See chapter 2 in «PROBLEM SYMPTOMS TABLE»(ref-209546-S11825380642005121000000) ) OK: GO TO NEXT STEP. NG: REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSY (See «TRANSMISSION VALVE BODY ASSY (U151E/U151F)»(ref-209590-S36275406272005121000000) )
3. INSPECT TORQUE CONVERTER CLUTCH ASSY (See «TORQUE CONVERTER CLUTCH AND DRIVE PLATE (ATM)»(ref-209590-S35507545572005121000000) ) OK: REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSY (See «AUTOMATIC TRANSAXLE ASSY (U151E/U151F)»(ref-209590-S25711046832005121000000) ) NG: REPLACE TORQUE CONVERTER CLUTCH ASSY

The ECM commands gearshift by turning the shift solenoid valves "ON/OFF". When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem and the MIL comes on. Illuminating the MIL, the ECM performs the fail-safe and turns the other shift solenoid valves in good condition "ON/OFF" (In case of an open or short circuit, the ECM stops sending current to the circuit).

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1. INSPECT TRANSMISSION WIRE (SL2) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. OK: Standard (Check for short): OK: GO TO NEXT STEP. NG: Go to step 3
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission connector to the transaxle. Disconnect the connector from the ECM. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. OK: Standard (Check for short): OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )
3. INSPECT SHIFT SOLENOID VALVE (SL2) Remove the shift solenoid valve SL2. Measure the resistance according to the value(s) in the table below. Standard: Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve. Standard: The solenoid makes an operating noise. OK: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) ) NG: REPLACE SHIFT SOLENOID VALVE (SL2)

The NC terminal of ECM detects the counter gear speed sensor's revolving signal (output RPM). The ECM outputs a gearshift signal comparing the input turbine speed sensor (NT) with the counter gear speed sensor (NC).

When the ECM detects this code abnormally, the ECM performs the fail-safe and outputs a gearshift signal based on the signal from the input turbine speed sensor (NT).

While the vehicle is operating in the 2nd, 3rd, 4th or 5th gear position in the shift position of D, if the counter gear revolution is less than 300 RPM although the output shaft revolution is more than 1,000 RPM, the ECM detects the trouble.

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1. INSPECT SPEED SENSOR (NC) Disconnect the speed sensor connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: TOYOTA made: Standard: AISIN made: OK: GO TO NEXT STEP. NG: REPLACE SPEED SENSOR (NC)
2. CHECK HARNESS AND CONNECTOR (SPEED SENSOR - ECM) Connect the speed sensor connector. Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. Standard: TOYOTA made: Standard: AISIN made: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )

The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical troubles of the shift solenoid valves and valve body.

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The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual gear position (1st, 2nd, 3rd, 4th or 5th gear position). When the gear position commanded by the ECM and the actual gear position are not same, the ECM illuminates the MIL.

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ALL

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OFF malfunction (A)

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OFF malfunction (B)

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ON malfunction (A)

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ON malfunction (B)

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ON malfunction (C)

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1. INSPECT SHIFT SOLENOID VALVE (SL3) Remove the shift solenoid valve SL3. Measure the resistance according to the value(s) in the table below. Standard: Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve. Standard: The solenoid makes an operating noise. OK: GO TO NEXT STEP. NG: REPLACE SHIFT SOLENOID VALVE (SL3)
2. INSPECT TRANSMISSION VALVE BODY ASSY (See chapter 2 in «PROBLEM SYMPTOMS TABLE»(ref-209546-S11825380642005121000000) ) OK: GO TO NEXT STEP. NG: REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSY (See «TRANSMISSION VALVE BODY ASSY (U151E/U151F)»(ref-209590-S36275406272005121000000) )
3. INSPECT TORQUE CONVERTER CLUTCH ASSY (See «TORQUE CONVERTER CLUTCH AND DRIVE PLATE (ATM)»(ref-209590-S35507545572005121000000) ) OK: REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSY (See «AUTOMATIC TRANSAXLE ASSY (U151E/U151F)»(ref-209590-S25711046832005121000000) ) NG: REPLACE TORQUE CONVERTER CLUTCH ASSY

The ECM commands gearshift by turning the shift solenoid valves "ON/OFF". When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem and the MIL comes on. Illuminating the MIL, the ECM performs the fail-safe and turns the other shift solenoid valves in good condition "ON/OFF" (In case of an open or short circuit, the ECM stops sending current to the circuit).

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1. INSPECT TRANSMISSION WIRE (SL3) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: GO TO NEXT STEP. NG: Go to step 3
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission connector to the transaxle. Disconnect the connector from the ECM. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )
3. INSPECT SHIFT SOLENOID VALVE (SL3) Remove the shift solenoid valve SL3. Measure the resistance between terminals. Standard: Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve. Standard: The solenoid makes an operating noise. OK: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) ) NG: REPLACE SHIFT SOLENOID VALVE (SL3)

The ECM commands gearshift by turning the shift solenoid valves "ON/OFF". When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem and the MIL comes on. Illuminating the MIL, the ECM performs the fail-safe and turns the other shift solenoid valves in good condition "ON/OFF" (In case of an open or short circuit, the ECM stops sending current to the circuit).

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P0982

(A) Range check (Low resistance)

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P0983

(B) Range check (High resistance)

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1. INSPECT TRANSMISSION WIRE (S4) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: OK: GO TO NEXT STEP. NG: Go to step 3
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission connector to the transaxle. Disconnect the connector from the ECM. Measure the resistance according to the value(s) in the table below. Standard: OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )
3. INSPECT SHIFT SOLENOID VALVE (S4) Remove the shift solenoid valve S4. Measure the resistance according to the value(s) in the table below. Standard: Connect positive (+) lead to the terminal of solenoid connector, negative (-) lead to the solenoid body. Standard: The solenoid makes an operating noise. OK: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) ) NG: REPLACE SHIFT SOLENOID VALVE (S4)

The ECM commands gearshift by turning the shift solenoid valves "ON/OFF". When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem and the MIL comes on. Illuminating the MIL, the ECM performs the fail-safe and turns the other shift solenoid valves in good condition "ON/OFF" (In case of an open or short circuit, the ECM stops sending current to the circuit).

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P0985

(A) Range check (Low resistance)

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P0986

(B) Range check (High resistance)

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1. INSPECT TRANSMISSION WIRE (SR) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: OK: GO TO NEXT STEP. NG: Go to step 3
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission connector to the transaxle. Disconnect the connector from the ECM. Measure the resistance according to the value(s) in the table below. Standard: OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )
3. INSPECT SHIFT SOLENOID VALVE (SR) Remove the shift solenoid valve SR. Measure the resistance according to the value(s) in the table below. Standard: Connect positive (+) lead to the terminal of solenoid connector, negative (-) lead to the solenoid body. Standard: The solenoid makes an operating noise. OK: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) ) NG: REPLACE SHIFT SOLENOID VALVE (SR)

The linear solenoid valve (SLT) controls the transmission line pressure for smooth transmission operation based on signals from the throttle position sensor and the vehicle speed sensor. The ECM adjusts the duty cycle of the SLT solenoid valve to control hydraulic line pressure coming from the primary regulator valve. Appropriate line pressure assures smooth shifting with varying engine outputs. When an open or short in the linear solenoid valve (SLT) circuit is detected, the ECM interprets this as a fault. The ECM will turn ON the MIL.

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1. INSPECTION TRANSMISSION WIRE (SLT) Disconnect the transmission wire connector from the transaxle. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: GO TO NEXT STEP. NG: Go to step 3
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) Connect the transmission wire connector to the transaxle. Disconnect the ECM connector. Measure the resistance according to the value(s) in the table below. Standard: Measure the resistance according to the value(s) in the table below. Standard (Check for short): OK: REPLACE ECM (See ECM (3MZ-FE) in ENGINE CONTROL SYSTEM ) NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-215923-S29911983652006011900000) )
3. INSPECT SHIFT SOLENOID VALVE (SLT) Remove the shift solenoid valve (SLT). Measure the resistance according to the value(s) in the table below. Standard: Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve. Standard: The solenoid makes an operating noise. OK: REPAIR OR REPLACE TRANSMISSION WIRE (See «TRANSMISSION WIRE (U151E/U151F)»(ref-209590-S29192554212005121000000) ) NG: REPLACE SHIFT SOLENOID VALVE (SLT)

Torque converter lock-up is controlled by the ECM based on engine RPM, engine load, engine temperature, vehicle speed, transmission temperature, and range selection. The ECM determines the lock-up status of the torque converter by comparing the engine RPM (NE) to the input turbine RPM (NT). The ECM calculates the actual transmission gear by comparing input turbine RPM (NT) to counter gear RPM (NC). When conditions are appropriate, the ECM requests "lock-up" by applying control voltage to shift solenoid DSL. When opened, solenoid DSL applies pressure to the lock-up relay valve and locks the torque converter clutch. If the ECM detects an open or short in the DSL solenoid circuit, the ECM interprets this as a fault in the DSL solenoid or circuit. The ECM will turn on the MIL.

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