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MR2 With Sequential Manual Transaxle

NOTE: A standard type manual transaxle and a sequential manual transaxle may be used. On models with a standard type manual transaxle, the driver operates the clutch and shifts the transaxle. On models with sequential manual transaxle, the transaxle is electronically controlled and the clutch is operated and transaxle is shifted hydraulically by moving shift lever forward or backward. Sequential manual transaxle may be identified by shift lever pattern which consists of "R", "N", "S" and "+" in place of the conventional type shift lever pattern and there is no clutch pedal. On this model, Electronic Throttle Control System (ETCS) is used for controlling idle speed. ETCS consists of throttle body, accelerator pedal position sensor, Throttle Position (TP) sensor, throttle control motor, magnetic clutch and Engine Control Module (ECM).
  1. Ensure throttle cable and throttle lever on throttle body move smoothly. Note location of throttle control motor on throttle body. See Fig 1.
    Fig 1: Locating Electronic Throttle Control System Components On Throttle Body (MR2 With Sequential Manual Transaxle)
    G00028687Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. To check throttle control motor operation, turn ignition on. Rotate throttle lever on throttle body to full throttle while listing for operating sound at throttle control motor and note that no grinding noise is heard at throttle control motor and throttle body. Throttle lever will also rotate accelerator pedal position sensor.
  3. If throttle control motor operating sound is heard, go to next step. If throttle control motor operating sound is not heard, throttle control motor, wiring harness or ECM may be defective. ECM is located on inside of firewall, directly behind driver's seat and luggage compartment. For illustration of ECM location, see THEORY & OPERATION article. To remove components for access to ECM, see ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article. Go to step  12 for testing of throttle control motor. For wiring of throttle control motor, see WIRING DIAGRAMS article.
  4. To test operation of accelerator pedal position sensor, Toyota hand-held tester may be used or voltmeter may be used. If using hand-held tester, go to next step. If using voltmeter, go to step  8.
  5. Connect hand-held tester to data link connector No. 3 at driver's side of instrument panel. See Figure. Hand-held tester is used to read throttle valve opening which is displayed as a percentage. Ensure Malfunction Indicator Light (MIL) on instrument panel is not illuminated. MIL is displayed as an engine icon. If MIL is not illuminated, go to next step. If MIL is illuminated, a Diagnostic Trouble Code (DTC) may be stored in ECM. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article for retrieving of DTCs.
  6. Rotate throttle lever on throttle body to full throttle while reading throttle valve opening on hand-held tester which is accessed by THROTTLE POS under CURRENT DATA. Throttle lever will also rotate accelerator pedal position sensor. Throttle valve opening should be 60 percent or more.
  7. If throttle valve opening is at least 60 percent, go to step  10. If throttle valve opening is not at least 60 percent, problem may exist in accelerator pedal position sensor, wiring circuit or ECM. Go to step  16 for testing of accelerator pedal position sensor. For wiring of accelerator pedal position sensor, see WIRING DIAGRAMS article.
  8. Access ECM. ECM is located on inside of firewall, directly behind driver's seat and luggage compartment. For illustration of ECM location, see THEORY & OPERATION article. To remove components for access to ECM, see ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  9. Ensure ignition is on. Using voltmeter, check voltage between ECM terminals VPA (Blue wire) and E2 (Brown wire) with accelerator pedal released and with accelerator pedal fully depressed. See Fig 2. Voltage should .3-.9 volt with accelerator pedal released and 3.2-4.7 volts with accelerator pedal fully depressed. If voltage is within specification, go to next step. If voltage is not within specification, problem may exist in accelerator pedal position sensor, wiring circuit or ECM. Go to step  16 for testing of accelerator pedal position sensor. For wiring of accelerator pedal position sensor, see WIRING DIAGRAMS article.
    Fig 2: Testing Voltage At Engine Control Module Terminals VPA & E2 (MR2 With Sequential Manual Transaxle)
    G00020839Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. Start engine and allow engine to idle. Check operation of Malfunction Indicator Light (MIL) on instrument panel. MIL is displayed as an engine icon. If MIL is not illuminated, go to next step. If MIL is illuminated, a Diagnostic Trouble Code (DTC) may be stored in Engine Control Module (ECM). See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article for retrieving of DTCs.
  11. To test operation of air assist system, allow engine to warm to normal operating temperature. Apply parking brake. Place transaxle in Neutral. Ensure A/C is off. Note engine idle speed. Engine idle speed should be 700-800 RPM. If all previous steps have been performed, drive vehicle to verify proper operation of throttle body.
  12. To test throttle control motor, disconnect electrical connector at throttle control motor. See Fig 1. It may be necessary to remove throttle body for access to electrical connector at throttle control motor. If necessary to remove throttle body, see THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  13. Note terminal identification on throttle control motor. See Fig 3. Using ohmmeter, check resistance between specified terminals on throttle control motor. See THROTTLE CONTROL MOTOR RESISTANCE  table. If resistance is within specification, reinstall electrical connector. Go to next step. If resistance is not within specification, replace throttle body with throttle control motor as an assembly.
    THROTTLE CONTROL MOTOR RESISTANCE

    Terminal No. Ohms @ 68°F (20°C)
    1 & 2 .3-100.0
    3 & 4 4.2-5.2
    Fig 3: Identifying Terminals & Testing Throttle Control Motor (MR2 With Sequential Manual Transaxle)
    G00020843Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  14. To test TP sensor, it may be necessary to remove throttle body for access to electrical connector at TP sensor. If necessary to remove throttle body, see THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  15. Disconnect electrical connector at TP sensor. See Fig 1. Using ohmmeter, check resistance between terminals E2 and VC on TP sensor. See Fig 4. Replace TP sensor if resistance is not 1200-3200 ohms at 68°F (20°C). See THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  16. To test accelerator pedal position sensor, it may be necessary to remove throttle body for access to electrical connector at TP sensor. If necessary to remove throttle body, see THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
  17. Disconnect electrical connector at accelerator pedal position sensor. See Fig 1. Using ohmmeter, check resistance between terminals E2 and VC on accelerator pedal position sensor. See Fig 5. Replace accelerator pedal position sensor if resistance is not 1200-3200 ohms at 68°F (20°C). See THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
    Fig 4: Identifying Terminals & Testing Throttle Position Sensor (MR2 With Sequential Manual Transaxle)
    G00016697Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 5: Identifying Terminals & Testing Accelerator Pedal Position Sensor (MR2 With Sequential Manual Transaxle)
    G00020816Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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