Contents Wiring diagrams Section: Computer Relearn All sections

Computer Relearn Procedures Toyota Sienna II

Computer Relearn 1 illustration ~1281 words

INTRODUCTION

Note. Before replacing any component that scan tool suggests is faulty, ensure that all wiring connections and harness connectors are okay. Ensure that power and ground circuits are functioning properly. For circuit identification, see ENGINE PERFORMANCE in appropriate SYSTEM WIRING DIAGRAMS article in ELECTRICAL for vehicle being tested.

SERVICE PRECAUTIONS (PRIUS)

WARNINGWhen performing any inspection or service procedure on this vehicle, ensure following service precautions are followed to prevent personal injury or death due to the extremely high voltage.

The following service precautions must be followed

  1. Ensure ignition is off and ignition key is removed from ignition before performing any inspection or service procedure in engine compartment, as engine may automatically start and shut off when ignition is on and READY light is illuminated. READY light is displayed just above the shift lever position indicator on instrument cluster at center of instrument panel.
  2. Read all service and warning labels in engine compartment before performing any procedures in engine compartment.
  3. All high-voltage wiring harness connectors contain Orange connectors. DO NOT touch any wiring harness that contains Orange connectors.
  4. High-voltage battery and other high-voltage components may be identified by HIGH VOLTAGE caution labels on them. DO NOT touch these components.
  5. If necessary to inspect or service high-voltage system, ensure ignition is off. Remove service plug and wait at least 5 minutes to ensure high voltage is fully discharged before touching any high-voltage wiring harness, connectors or components. Service plug is located on service plug assembly at driver's side front corner of trunk compartment, near high-voltage battery. (Scheme 1) Ensure service plug is stored in a location in which no one may install service plug while technician is working on the vehicle.
  6. If necessary to touch any high-voltage wiring harness, connectors or components, ensure service plug is removed and battery voltage or less exists at electrical connector. Use Toyota insulated gloves when touching any high-voltage wiring harness, connectors or components. Ensure insulated gloves are dry and in good condition and that no holes exist in insulated gloves. Test insulated glove by applying air to glove before touching any high-voltage wiring harness, connectors or components.
  7. DO NOT wear any metal objects while working on vehicle which may accidently drop and cause a short circuit.
  8. If any high-voltage wiring harness connector is disconnected, ensure terminal on wiring harness connector is wrapped with tape to prevent wiring harness connector from contacting any surface.
  9. If servicing high-voltage system, place sign on roof of vehicle to indicate to other technicians that high-voltage system is being serviced.

Scheme 1

Scheme 1

BODY CONTROLS

Vehicles equipped with body, air conditioning, anti-lock brake or memory computers may require a computer relearn procedure after components are replaced or the vehicle battery is disconnected. Vehicle computers memorize and store vehicle information and operation selections. When the vehicle battery is disconnected, vehicle computer memory may be lost, requiring relearning or resetting. Depending on the vehicle and how it is equipped, the following memories may exist

  1. Seat position.
  2. Tilt/telescoping steering wheel position.
  3. Mirror position.
  4. Radio presets and anti-theft code.
  5. Clock.
  6. Remote keyless entry custom features.
  7. Door key lock entry custom features.
  8. Power window or sunroof operation.

These do not affect vehicle operation. For systems that do not affect operation, see appropriate article for relearn procedures. Other computer relearn procedures are required for vehicle or system operation. These may include

  1. Initial control unit programming.
  2. Traction control yaw sensor initializing.
  3. Multiplex communication.
  4. Anti-theft system or engine immobilizer system passwords.

ENGINE CONTROLS

Vehicles equipped with powertrain control computers may require a computer relearn procedure after the vehicle battery is disconnected. Vehicle computers memorize and store vehicle operation patterns for optimum driveability and performance. When the vehicle battery is disconnected, this memory is lost, which may result in a driveability problem. Depending on the vehicle and how it is equipped, the following driveability problems may exist

  1. Rough or unstable idle.
  2. Hesitation or stumble.
  3. Rich or lean running.
  4. Poor fuel mileage.
  5. Harsh or poor transmission/transaxle shift quality.

Default data is used until NEW data from each key start is stored. As the computer restores its memory from each new key start, driveability is restored.

Driveability problems may occur during the computer relearn stage. To accelerate computer relearn process after battery removal and installation, specified computer relearn procedures should be performed. See appropriate procedure for specific model.

TOYOTA VEHICLE IMMOBILIZER SYSTEM

Toyota Vehicle Immobilizer System (TVIS) must be initialized after Engine Control Module (ECM) has been replaced. See appropriate ENGINE IMMOBILIZER SYSTEMS article under DOOR LOCKS & ANTI-THEFT SYSTEMS in ACCESSORIES & EQUIPMENT.

POWER SLIDING DOOR REINITIALIZATION PROCEDURE (SIENNA)

Note. Following procedure should be performed if power sliding door system does not operate properly under the following conditions: battery is disconnected and reconnected, battery is discharged and recharged, or open power sliding door warning light remains on even with power sliding doors closed.

  1. If power sliding door system does not operate properly and open power sliding door warning light remains on, even with power sliding doors closed, go to next step. If power sliding door system does not operate properly after battery is disconnected and reconnected or battery is discharged and recharged, go to step 4 .
  2. Ensure power sliding door main switch is in OFF position. Power sliding door main switch is located on driver's side of instrument panel, just to the left of steering column and is marked as PWR DOOR OFF. Close power sliding door by hand. Disconnect battery for one minute and then reconnect the battery.
  3. Turn on power sliding door system by placing power sliding door main switch in the ON position. Wait 5 seconds and then go to next step.
  4. Ensure power sliding door main switch is in ON position if not previously done. Power sliding door main switch is located on driver's side of instrument panel, just to the left of steering column and is marked as PWR DOOR OFF. Open one of the power sliding doors by using the power sliding door control switch. Power sliding door control switches are located near center of instrument panel, just below the stereo.
  5. Wait 3 seconds after power sliding door stops at the fully open position and then close power sliding door by using power sliding door control switch on instrument panel or by using remote keyless entry transmitter.
  6. Wait 3 seconds after power sliding door stops at the fully closed position and then repeat steps 4 and 5 .

Camry

Note. Following procedure should be performed if battery is disconnected and reconnected, or battery is discharged and recharged to provide proper automatic operation and jam protection operation of power sun roof.

  1. Ensure ignition is on. Depress and hold TILT UP side of power sun roof switch until power sun roof tilts all the way upward and then tilts downward a little. Power sun roof switch is located on headliner, just in front of power sun roof.
  2. Check proper operation of open/closing and tilt up/down function for power sun roof using power sun roof switch. Power sun roof should operate anytime ignition is on, or for 43 seconds after ignition is off provided both front doors are closed. It will stop operating if any front door is opened. Depressing SLIDE OPEN side of power sun roof switch for one second should open power sun roof.
  3. Depressing TILT UP side of power sun roof switch for one second should close power sun roof. To tilt power sun roof upward, depress and hold TILT UP side of power sun roof switch for one second. To tilt power sun roof downward, depress and hold SLIDE OPEN side of power sun roof switch for one second.

Celica

Close power sun roof using power sun roof switch and continue to depress power sun roof switch briefly after power sun roof is fully closed. Power sun roof switch is located on headliner, just in front of power sun roof.