Automatic Transaxle (Diagnostic Codes & Circuit Tests): Overview Scion tC II

DESCRIPTION

The speed sensors detect the wheel speed and send the appropriate signals to the skid control ECU. The skid control ECU converts these wheel speed signals into a pulse signal and outputs it to the TCM via the combination meter. The TCM determines the vehicle speed based on the frequency of this pulse signal.

Scheme 392

MONITOR DESCRIPTION

The TCM assumes that the vehicle is being driven when the transmission counter gear speed is more than 300 rpm and over 30 seconds have passed since the park/neutral position switch was turned off. If there is no vehicle speed signal with these conditions satisfied, the TCM concludes that there is a vehicle speed signal malfunction. The TCM will turn on the MIL and store the DTC.

The battery supplies electricity to the TCM even when the ignition switch is off. This power allows the TCM to store data such as DTC history and freeze frame data. If the battery voltage falls below a minimum level, this memory is cleared and the TCM determines that there is a malfunction in the power supply circuit. When the engine is next started, the TCM will illuminate the MIL and store the DTC.

HINT

If DTC P0560 is stored, the TCM does not store other DTCs.

While the engine is being cranked, battery voltage is applied to terminal STA of the TCM.

If the TCM detects the starter control (STA) signal while the vehicle is being driven, it determines that there is a malfunction in the STA circuit. The TCM then illuminates the MIL and stores the DTC.

This monitor runs when the vehicle is driven at 20 km/h (12.43 mph) or more for over 20 seconds.

The TCM monitors its internal operation and it stores this DTC when it detects an internal malfunction.

The TCM monitors its internal operation. If there is a problem in its internal operation, the TCM illuminates the MIL and stores a DTC.

The park/neutral position switch detects the shift lever position and sends signals to the TCM.

This DTC indicates a problem with the park/neutral position switch and/or the wire harness in the park/neutral position switch circuit.

The park/neutral position switch detects the shift lever position (P, R or D) and sends a signal to the TCM.

For safety, the park/neutral position switch detects the shift lever position so that the engine cannot be started when the shift lever is not in P or N.

The TCM determines that there is a problem with the switch or related parts if it receives more than 1 position signal simultaneously, or receives no position signal at all.

The ATF temperature sensor converts the fluid temperature into a resistance value for use by the TCM.

The TCM applies a voltage to the temperature sensor through terminal OIL of the TCM.

The sensor resistance changes with the ATF temperature. As the temperature becomes higher, the sensor resistance decreases.

One terminal of the sensor is grounded so that the sensor resistance and voltage decrease as the temperature becomes higher.

The TCM calculates the fluid temperature based on the voltage signal.

This DTC indicates that there is a problem with output signals from the ATF temperature sensor and that the sensor itself is defective. The ATF temperature sensor converts the ATF temperature into an electrical resistance value. Based on the resistance, the TCM determines the ATF temperature and detects an open or short in the ATF temperature circuit or a fault of the ATF temperature sensor.

After driving the vehicle for a certain period, the ATF temperature should increase. If the ATF temperature is below 20°C (68°F) after driving the vehicle for a certain period, the TCM interprets this as a fault, turns on the MIL and stores the DTC.

Refer to DTC P0711. Refer to DESCRIPTION .

These DTCs indicate an open or short in the ATF temperature sensor circuit. The ATF temperature sensor converts ATF temperature into an electrical resistance value. Based on the resistance, the TCM determines the ATF temperature, and the TCM detects an open or short in the ATF temperature circuit. If the resistance value of the ATF temperature is below 79 ohms*1 or higher than 156 kohms*2, the TCM interprets this as a fault in the ATF sensor or wiring. The TCM will turn on the MIL and store the DTC.

HINT

1. The ATF temperature can be checked on the Techstream display.
2. *1: 150°C (302°F) or higher is indicated regardless of the actual ATF temperature.
3. *2: -40°C (-40°F) is indicated regardless of the actual ATF temperature.

This sensor detects the rotation speed of the turbine which indicates the input speed of the transaxle. By comparing the input turbine speed (speed sensor NT) signal with the counter gear speed (speed sensor NC) signal, the TCM detects the shift timing of the gears and appropriately controls the engine torque and hydraulic pressure according to various conditions. As a result, the gears shift smoothly.

The NT terminal of the TCM detects a pulse signal from the speed sensor NT (input RPM). The TCM calculates gear shifts by comparing the signal from speed sensor NT with the signal from speed sensor NC.

While the transaxle is operating in 2nd, 3rd, 4th, 5th or 6th gear with the shift lever in D, if the input shaft speed is less than 300 rpm*1 although the output shaft speed is more than 1000 rpm*2, the TCM interprets this as a fault, illuminates the MIL and stores the DTC.

HINT

1. *1: A pulse is not output or is irregularly output.
2. *2: The vehicle speed is 50 km/h (31 mph) or more.

The purpose of this circuit is to prevent the engine from stalling when the brakes are suddenly applied while driving in lock-up.

When the brake pedal is depressed, this switch sends a signal to the TCM. Then the TCM cancels the operation of the lock-up clutch while braking is in progress.

This DTC indicates that the stop light switch remains on. When the stop light switch remains on during "stop and go" driving, the TCM interprets this as a fault in the stop light switch, illuminates the MIL and stores the DTC. The vehicle must stop (less than 3 km/h (1.86 mph) and go (30 km/h (18.65 mph) or more) five times for two consecutive driving cycles in order for this DTC to be stored.

The TCM uses signals from the throttle position sensor, air flow meter, turbine (input) speed sensor, intermediate (counter gear) speed sensor and crankshaft position sensor to help determine the engagement timing of the lock-up clutch. The TCM monitors the engagement of the clutch using the turbine (input) speed sensor, intermediate (counter gear) speed sensor and crankshaft position sensor.

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

Torque converter lock-up is controlled by the TCM based on the speed sensor NT, speed sensor NC, engine speed, engine load, engine temperature, vehicle speed, ATF temperature and gear selection. The TCM determines the lock-up status of the torque converter by comparing the engine speed (NE) to the input turbine speed (NT). The TCM calculates the actual transmission gear by comparing the input turbine speed (NT) to the counter gear speed (NC). When conditions are appropriate, the TCM requests "lock-up" by applying control voltage to shift solenoid valve SL. When shift solenoid valve SL is turned on, it applies pressure to the lock-up relay valve and locks the torque converter.

If the TCM detects no lock-up after lock-up has been requested or if it detects lock-up when it is not requested, the TCM interprets this as a fault in shift solenoid valve SL or lock-up system performance. The TCM will turn on the MIL and store the DTC.

HINT

Example

When any of the following is met, the system judges it to be a malfunction.

1. There is a difference in rotation speed between the input side (engine speed) and output side (input turbine speed) of the torque converter when the TCM commands lock-up. (Engine speed is at least 70 rpm more than the input turbine speed.)
2. There is no difference in rotation speed between the input side (engine speed) and output side (input turbine speed) of the torque converter when the TCM commands lock-up off. (The difference between the engine speed and input turbine speed is less than 20 rpm.)

The TCM uses the vehicle speed signal and signals from the transmission speed sensors (NC, NT) to detect the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear).

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

The TCM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft speed, intermediate (counter) shaft speed and output shaft speed, the TCM detects the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear). When the gear commanded by the TCM and the actual gear are not the same, the TCM illuminates the MIL and stores the DTC.

Shifting from 1st to 6th is performed by the TCM turning shift solenoid valves SL1, SL2, SL3, SL4 and SL on and off. If an open or short circuit occurs in any of the shift solenoid valves, the TCM controls the remaining normal shift solenoid valves to allow the vehicle to be operated. Refer to FAIL-SAFE CHART .

This DTC indicates an open or short in the shift solenoid valve SL1 circuit. The TCM commands gear shifts by turning the shift solenoid valves on or off. When there is an open or short circuit in any shift solenoid valve circuit, the TCM detects the problem, illuminates the MIL and stores the DTC. The TCM also performs the fail-safe function and turns the other normal shift solenoid valves on or off (in case of an open or short circuit, the TCM stops sending current to the circuit).

While driving and shifting between 4th and 5th gears, if the TCM detects an open or short in the shift solenoid valve SL1 circuit, the TCM determines there is a malfunction. Refer to FAIL-SAFE CHART .

The TCM uses the vehicle speed signal and signals from the transmission speed sensors (NC, NT) to detect the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear).

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

The TCM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft speed, intermediate (counter) shaft speed and output shaft speed, the TCM detects the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear). When the gear commanded by the TCM and the actual gear are not the same, the TCM illuminates the MIL and stores the DTC.

Shifting from 1st to 6th is performed by the TCM turning shift solenoid valves SL1, SL2, SL3, SL4 and SL on and off. If an open or short circuit occurs in any of the shift solenoid valves, the TCM controls the remaining normal shift solenoid valves to allow the vehicle to be operated. Refer to FAIL-SAFE CHART .

This DTC indicates an open or short in the shift solenoid valve SL2 circuit. The TCM commands gear shifts by turning the shift solenoid valves on or off. When there is an open or short circuit in any of the shift solenoid valve circuits, the TCM detects the problem, illuminates the MIL and stores the DTC. The TCM also performs the fail-safe function and turns the other normal shift solenoid valves on or off (in case of an open or short circuit, the TCM stops sending current to the circuit).

While driving and shifting gears, if the TCM detects an open or short in the shift solenoid valve SL2 circuit, the TCM determines there is a malfunction. Refer to FAIL-SAFE CHART .

This sensor detects the rotation speed of the counter gear which indicates the output speed of the transaxle. By comparing the input turbine speed (speed sensor NT) signal with the counter gear speed (speed sensor NC) signal, the TCM detects the shift timing of the gears and appropriately controls the engine torque and hydraulic pressure according to various conditions. As a result, the gears shift smoothly.

The NT terminal of the TCM detects a pulse signal from the speed sensor NT (input RPM). The TCM calculates gear shifts by comparing the signal from speed sensor NT with the signal from speed sensor NC.

While the vehicle is operating in 2nd, 3rd, 4th or 5th gear with the shift lever in D, if the input shaft speed is less than 300 rpm*1 although the output shaft speed is more than 1000 rpm*2, the TCM interprets this as a fault, illuminates the MIL and stores the DTC.

HINT

1. *1: A pulse is not output or is irregularly output.
2. *2: The vehicle speed is 50 km/h (31 mph) or more.

The TCM uses the vehicle speed signal and signals from the transmission speed sensors (NC, NT) to detect the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear).

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

The TCM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft speed, intermediate (counter) shaft speed and output shaft speed, the TCM detects the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear). When the gear commanded by the TCM and the actual gear are not the same, the TCM illuminates the MIL and stores the DTC.

Shifting from 1st to 6th is performed by the TCM turning shift solenoid valves SL1, SL2, SL3, SL4 and SL on and off. If an open or short circuit occurs in any of the shift solenoid valves, the TCM controls the remaining normal shift solenoid valves to allow the vehicle to be operated. Refer to FAIL-SAFE CHART .

The TCM commands gear shifts by turning the shift solenoid valves on or off. When there is an open or short circuit in any shift solenoid valve circuit, the TCM detects the problem, illuminates the MIL and stores the DTC. The TCM also performs the fail-safe function and turns the other normal shift solenoid valves on or off (in case of an open or short circuit, the TCM stops sending current to the circuit). Refer to FAIL-SAFE CHART .

Shift solenoid valve SLT controls the transmission line pressure for smooth transmission operation based on signals from the throttle position sensor and vehicle speed sensor. The TCM adjusts the current to shift solenoid valve SLT to control hydraulic line pressure coming from the primary regulator valve. Appropriate line pressure assures smooth shifting with varying engine outputs.

Scheme 393

The TCM calculates the amount of heat absorbed by the friction material based on the difference in speed (clutch slippage) between the turbine and output shaft. The TCM turns on the MIL and stores this DTC when the amount of heat absorption exceeds the specified value.

When shift solenoid valve SLT remains on, the line pressure goes down and clutch engagement force decreases.

Note. If driving continues under these conditions, clutches will burn out and the vehicle will no longer be drivable.

Refer to DTC P2714. Refer to DESCRIPTION .

When an open or short in the shift solenoid valve SLT circuit is detected, the TCM interprets this as a fault. The TCM will turn on the MIL and store the DTC.

The TCM uses the signals from the throttle position sensor, air flow meter, input turbine speed sensor, output speed sensor and crankshaft position sensor to monitor the engagement condition of the lock-up clutch.

The TCM compares the engagement condition of the lock-up clutch with the lock-up schedule in the TCM memory to detect shift solenoid valve SLU, valve body and torque converter mechanical problems.

Scheme 394

Torque converter lock-up is controlled by the TCM based on the input turbine speed sensor (speed sensor NT), output speed sensor (speed sensor NC), engine speed, engine load, engine temperature, vehicle speed, ATF temperature and gear selection. The TCM determines the lock-up status of the torque converter by comparing the engine speed (NE) to the input turbine speed (NT). The TCM calculates the actual transmission gear by comparing the input turbine speed (NT) to the output shaft speed (NC). When conditions are appropriate, the TCM requests "lock-up" by applying control voltage to shift solenoid valve SLU. When shift solenoid valve SLU is turned on, it applies pressure to the lock-up relay valve and locks the torque converter.

If the TCM detects no lock-up after lock-up has been requested or if it detects lock-up when it is not requested, the TCM interprets this as a fault in shift solenoid valve SLU or lock-up system performance.

The TCM will turn on the MIL and store the DTC.

Example

When either of the following is met, the system judges it to be a malfunction.

1. There is a difference in speed between the input side (engine speed) and output side (input turbine speed) of the torque converter when the TCM commands lock-up. (Engine speed is at least 70 rpm more than input turbine speed.)
2. There is no difference in speed between the input side (engine speed) and output side (input turbine speed) of the torque converter when the TCM commands lock-up off. (The difference between engine speed and input turbine speed is less than 20 rpm.)

The amount of current flow to shift solenoid valve SLU is controlled by the TCM. The higher the current becomes, the higher the lock-up hydraulic pressure becomes during the lock-up operation.

When an open or short in the shift solenoid valve SLU circuit is detected, the TCM determines there is a malfunction. The TCM will turn on the MIL and store the DTC.

Shift solenoid valve SL is turned on and off by signals from the TCM to control the hydraulic pressure acting on the lock-up relay valve, which then controls operation of the lock-up clutch.

Fail-safe function

If the TCM detects a malfunction, it turns shift solenoid valve SL off.

Based on the signals from the throttle position sensor, air flow meter and crankshaft position sensor, the TCM sends a signal to shift solenoid valve SL to regulate the hydraulic pressure and provide smooth torque converter engagement. Shift solenoid valve SL responds to commands from the TCM. The valve controls the lock-up relay valve to perform the torque-converter lock-up function. If the TCM detects an open or short circuit for shift solenoid valve SL, it will illuminate the MIL and store the DTC.

The TCM uses the vehicle speed signal and signals from the transmission speed sensors (NC, NT) to detect the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear).

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

The TCM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft speed, intermediate (counter) shaft speed and output shaft speed, the TCM detects the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear). When the gear commanded by the TCM and the actual gear are not the same, the TCM illuminates the MIL and stores the DTC.

Shifting from 1st to 6th is performed by the TCM turning shift solenoid valves SL1, SL2, SL3, SL4 and SL on and off. If an open or short circuit occurs in any of the shift solenoid valves, the TCM controls the remaining normal shift solenoid valves to allow the vehicle to be operated. Refer to FAIL-SAFE CHART .

The TCM commands gear shifts by turning the shift solenoid valves on or off. When there is an open or short circuit in any shift solenoid valve circuit, the TCM detects the problem, illuminates the MIL and stores the DTC. The TCM also performs the fail-safe function and turns the other normal shift solenoid valves on or off (in case of an open or short circuit, the TCM stops sending current to the circuit). Refer to FAIL-SAFE CHART .

The ECM communicates with the TCM using the Controller Area Network (CAN).

If there is a problem with this communication, the TCM stores a DTC.

After moving the shift lever to S, it is possible to switch the shift range between "1" (S1 range) and "6" (S6 range) using the transmission control switch.

Moving the shift lever to "+" once raises the shift range by one, and moving the shift lever to "-" once lowers the shift range by one.

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1. INSPECT TRANSMISSION CONTROL SWITCH Disconnect the transmission control switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 6 (IG) - 13 (S) Shift lever in S, "+" or "-" Below 1 ohms 5 (SFTU) - 11 (E) Shift lever held in "+" (Up-shift) Below 1 ohms 4 (SFTD) - 11 (E) Shift lever held in "-" (Down-shift) Below 1 ohms 6 (IG) - 13 (S) Shift lever not in S, "+" or "-" 10 kohms or higher 5 (SFTU) - 11 (E) Shift lever in S 10 kohms or higher 4 (SFTD) - 11 (E) Shift lever in S 10 kohms or higher TEXT IN ILLUSTRATION *a Component without harness connected (Transmission Control Switch) NG --> See step 5 OK: Go to next step
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - BATTERY AND BODY GROUND) Disconnect the transmission control switch connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition C47-6 (IG) - Body ground Ignition switch ON 11 to 14 V C47-6 (IG) - Body ground Ignition switch off Below 1 V Turn the ignition switch off. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition C47-11 (E) - Body ground Always Below 1 ohms TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Transmission Control Switch) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
3. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - ECM) Disconnect the ECM connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition A35-14 (S) - Body ground Ignition switch ON Shift lever in S, "+" or "-" 11 to 14 V A35-14 (S) - Body ground Ignition switch ON Shift lever not in S, "+" or "-" Below 1 V Turn the ignition switch off. Disconnect the spiral cable with sensor sub-assembly connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition A35-16 (SFTU) - Body ground Shift lever held in "+" (Up-shift) Below 1 ohms A35-51 (SFTD) - Body ground Shift lever held in "-" (Down-shift) Below 1 ohms A35-16 (SFTU) - Body ground Shift lever in S 10 kohms or higher A35-51 (SFTD) - Body ground Shift lever in S 10 kohms or higher TEXT IN ILLUSTRATION *a Front view of wire harness connector (to ECM) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 4
4. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(ref-451062-S33666616312012020700000)
5. REPLACE TRANSMISSION CONTROL SWITCH (SHIFT LOCK CONTROL UNIT ASSEMBLY). Refer to «REMOVAL»(ref-451170-S35025316732012020700000)

When the shift lever is in S, the shift range can be changed using the shift paddle switches. It is also possible to select the shift range when the vehicle is being driven with the shift lever in D by operating the shift paddle switches.

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1. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE - BODY GROUND) Disconnect the spiral cable connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition C8-2 (ECC) - Body ground Always Below 1 ohms TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Spiral Cable with Sensor Sub-assembly) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
2. INSPECT SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY Remove the spiral cable with sensor sub-assembly. Refer to «REMOVAL»(ref-451209-S23229061362012020700000) . Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition z21-2 (SUP) - C8-9 (SUP) Always Below 1 ohms z21-3 (SDN) - C8-10 (SDN) Always Below 1 ohms z21-6 (ECC) - C8-2 (ECC) Always Below 1 ohms TEXT IN ILLUSTRATION *a Component without harness connected (Spiral Cable with Sensor Sub-assembly) NG --> See step 8 OK: Go to next step
3. INSPECT TRANSMISSION SHIFT SWITCH ASSEMBLY (LH (-) AND RH (+)) Remove the transmission shift switch assembly. Refer to «REMOVAL»(ref-451170-S01348184122012020700000) . Measure the resistance according to the value(s) in the table below. Standard Resistance FOR LH Tester Connection Switch Condition Specified Condition SDN - ECC "-" shift paddle operated and held (down-shift) Below 2.5 ohms SDN - ECC "-" shift paddle not operated (down-shift) 1 Mohms or higher FOR RH Tester Connection Switch Condition Specified Condition SUP - ECC "+" shift paddle operated and held (up-shift) Below 2.5 ohms SUP - ECC "+" shift paddle not operated (up-shift) 1 Mohms or higher TEXT IN ILLUSTRATION *A for LH *B for RH *a Component without harness connected (Transmission Shift Switch Assembly) NG --> See step 9 OK: Go to next step
4. INSPECT NO. 1 SWITCH WIRE Disconnect the No. 1 switch wire connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Switch Condition Specified Condition SDN - ECC "-" shift paddle operated and held (down-shift) Below 2.5 ohms SUP - ECC "+" shift paddle operated and held (up-shift) Below 2.5 ohms SDN - ECC "-" shift paddle not operated (down-shift) 1 Mohms or higher SUP - ECC "+" shift paddle not operated (up-shift) 1 Mohms or higher TEXT IN ILLUSTRATION *a Component without harness connected (No. 1 Switch Wire) NG --> See step 10 OK: Go to next step
5. INSPECT STEERING PAD SWITCH LH Disconnect the steering pad switch LH connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Switch Condition Specified Condition z21-2 (SUP) - z21-6 (ECC) "+" shift paddle operated and held (up-shift) Below 2.5 ohms z21-3 (SDN) - z21-6 (ECC) "-" shift paddle operated and held (down-shift) Below 2.5 ohms z21-2 (SUP) - z21-6 (ECC) "+" shift paddle not operated (up-shift) 1 Mohms or higher z21-3 (SDN) - z21-6 (ECC) "-" shift paddle not operated (down-shift) 1 Mohms or higher TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Spiral Cable with Sensor Sub-assembly) NG --> See step 11 OK: Go to next step
6. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE - ECM) Disconnect the ECM connector. Disconnect the transmission control switch (shift lock control unit assembly) connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Switch Condition Specified Condition A35-16 (SFTU) - Body ground "+" shift paddle operated and held (up-shift) Below 2.5 ohms A35-51 (SFTD) - Body ground "-" shift paddle operated and held (down-shift) Below 2.5 ohms A35-16 (SFTU) - Body ground "+" shift paddle not operated (up-shift) 1 Mohms or higher A35-51 (SFTD) - Body ground "-" shift paddle not operated (down-shift) 1 Mohms or higher TEXT IN ILLUSTRATION *a Front view of wire harness connector (to ECM) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 7
7. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(ref-451062-S33666616312012020700000)
8. REPLACE SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY. Refer to «REMOVAL»(ref-451209-S23229061362012020700000)
9. REPLACE TRANSMISSION SHIFT SWITCH ASSEMBLY. Refer to «REMOVAL»(ref-451170-S01348184122012020700000)
10. REPLACE NO. 1 SWITCH WIRE. Refer to «REMOVAL»(ref-451170-S01348184122012020700000)
11. REPLACE STEERING PAD SWITCH LH. Refer to «REMOVAL»(ref-451170-S01348184122012020700000)

When the ignition switch is turned to ON, voltage from the MREL terminal of the ECM is applied to the EFI MAIN relay. This causes the contacts of the EFI MAIN relay to close, which supplies power to terminal +B of the TCM.