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Hybrid Control (Diagnostics - Introduction): Other Lexus HS I

Engine Control Systems 13 illustrations ~1397 words

DEFINITION OF TERMS

TermsDefinition
Monitor DescriptionDescription of what the hybrid vehicle control ECU monitors and how it detects malfunctions (monitoring purpose and its details).
Related DTCsA group of diagnostic trouble codes that are output by the hybrid vehicle control ECU based on the same malfunction detection logic.
Typical Enabling ConditionPreconditions that allow the hybrid vehicle control ECU to detect malfunctions. With all preconditions satisfied, the hybrid vehicle control ECU sets DTCs when the monitored value(s) exceeds malfunction threshold(s).
Sequence of OperationOrder of monitor priority, applied if multiple sensors and components are involved in a single malfunction detection process. Each sensor and component are monitored in turn and subsequent items are not monitored until the previous detection operation completes.
Required Sensor/ComponentsSensors and components used by the hybrid vehicle control ECU to detect each malfunction.
Frequency of OperationNumber of times the hybrid vehicle control ECU checks for each malfunction during each driving cycle. "Once per driving cycle" means that the hybrid vehicle control ECU only checks for malfunctions once during a single driving cycle. "Continuous" means that the hybrid vehicle control ECU checks for malfunctions whenever enabling conditions are met.
DurationMinimum time for which the hybrid vehicle control ECU must detect continuous deviation in monitored value(s) in order to set a DTC. Timing begins when typical enabling conditions are met.
Malfunction ThresholdsValue beyond which the hybrid vehicle control ECU determines malfunctions exist and sets DTCs.
MIL OperationTiming of MIL illumination after a malfunction is detected. "Immediate" means that the hybrid vehicle control ECU illuminates the MIL as soon as a malfunction is detected. "2 driving cycles" means that the hybrid vehicle control ECU illuminates the MIL if the same malfunction is detected again during the next driving cycle.

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Scheme 162: SYSTEM DIAGRAM

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Scheme 166: SYSTEM DESCRIPTION

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  1. BASIC OPERATION This system generates a motive force by combining the engine, MG1, and MG2 in accordance with the driving conditions. Representative examples of the various combinations are described below. Starting (Driven by MG2) Supply of electrical power from the HV battery to MG2 provides force to drive the front wheels. During Acceleration with Engine While the front wheels are being driven by the engine via the planetary gears, MG1 is also being driven by the engine via the planetary gears, in order to supply the electricity that MG1 generates to MG2. Charging the HV Battery MG1 is rotated by the engine via the planetary gears, in order to charge the HV battery. During Deceleration When the vehicle is decelerating, kinetic energy from the front wheels is recovered and converted into electrical energy by means of MG2, and used to recharge the HV battery.
  2. SYSTEM DIAGRAM
  3. FUNCTION OF MAIN COMPONENTS Component Function Hybrid Vehicle Control ECU Performs comprehensive control of the hybrid system. Information from various sensors as well as from ECUs (MG ECU, battery smart unit and skid control ECU) is received, and based on this, the required torque and output power is calculated. The hybrid vehicle control ECU transmits the calculated result to the MG ECU and skid control ECU. Activates the ETCS-i (Electronic Throttle Control System-intelligent) in accordance with the target engine speed and required engine motive force. Monitors the SOC of the HV battery. Controls the DC-DC converter. Controls the HV water pump with motor. Controls the HV battery cooling blower. Hybrid Vehicle Transaxle Assembly Motor Generator 1 (MG1) MG1, which is driven by the engine, generates high-voltage electricity in order to operate MG2 and charge the HV battery. Also, it functions as a starter to start the engine. Motor Generator 2 (MG2) MG2, which is driven by electrical power from MG1 and the HV battery, generates motive force for the drive wheels. During braking, or when the accelerator pedal is not depressed, it generates high-voltage electricity to recharge the HV battery. Resolver (for MG1/for MG2) Detects the rotor position, rotational speed and direction of MG1 and MG2. Temperature Sensor (for MG1/for MG2) Detects the temperature of MG1 and MG2. Compound Gear Unit Power Split Planetary Gear Unit Distributes the engine motive force as appropriate to directly drive the vehicle as well as MG1. Motor Speed Reduction Planetary Gear Unit Reduces the rotational speed of MG2 in accordance with the characteristics of the planetary gear, in order to increase torque. Inverter with Converter Assembly Inverter Converts the direct current from the boost converter into the alternating current for MG1 and MG2, and vice versa (from AC to DC). Boost Converter Boosts the maximum voltage of the HV battery from DC 244.8 to DC 650 V and vice versa (drops DC 650 V to DC 244.8 V). MG ECU Controls the inverter and boost converter in accordance with the signals received from the hybrid vehicle control ECU, thus operating MG1 and MG2 as either a generator or motor. Temperature Sensor (for Inverter with Converter Assembly) Detects temperatures in the parts of the inverter with converter assembly as well as the HV coolant temperature. Inverter Current Sensor Detects the current of MG1 and MG2. HV Battery Assembly HV Battery (Battery Modules) Supplies electrical power to MG1 and MG2 in accordance with the driving conditions of the vehicle. Recharged by MG1 and MG2 in accordance with the SOC and the driving conditions of the vehicle. HV Battery Temperature Sensors Detects temperatures in the parts of the HV battery and the intake air temperature from the HV battery cooling blower. Hybrid Vehicle Converter (DC/DC Converter) Converts a voltage of DC 244.8 V into a DC voltage between 12 V and 14 V in order to supply electricity to body electrical components, as well as to recharge the auxiliary battery (DC 12 V). Contains SMRP. Hybrid Battery Junction Block Assembly System Main Relays Connects and disconnects the high-voltage power circuit between the HV battery and the inverter with converter assembly, through the use of the signals from the hybrid vehicle control ECU. Contains SMRB and SMRG. HV Battery Current Sensor Detects the input and output current of the HV battery. Battery Smart Unit Monitors the conditions of the HV battery such as voltage, current and temperature, and transmits this information to the hybrid vehicle control ECU. Monitors the high-voltage system for breakdown of the electrical insulation. Service Plug Grip Shuts off the high-voltage circuit of the HV battery when the service plug grip is removed for vehicle inspection or maintenance. Interlock Switch (for A/C Fuse Cover and Service Plug Grip) Verifies that the cover of both the inverter and the service plug grip have been installed. Power Cable Connects the HV battery, inverter with converter assembly, hybrid vehicle transaxle assembly and cooler compressor with motor assembly. Water Pump with Motor Assembly Operates based on signals from the hybrid vehicle control ECU in order to cool the inverter with converter assembly and MG1. HV Battery Cooling Blower Operates based on signals from the hybrid vehicle control ECU in order to cool the HV battery. Auxiliary Battery Charged by HV battery power via the hybrid vehicle converter (DC/DC converter). Supplies power to the audio system, air conditioning system (except the electric inverter compressor) and the ECUs. Auxiliary Battery Thermometer (Temperature) Sensor Detects the temperature of the auxiliary battery. Accelerator Pedal Sensor Assembly Converts the accelerator pedal position into an electrical signal and outputs it to the hybrid vehicle control ECU. Shift Lever Position Sensor Converts the shift lever operation into an electrical signal and outputs it to the hybrid vehicle control ECU. P Position Switch (Transmission Shift Main Switch) Outputs the P position switch signal to the hybrid vehicle control ECU when operated by the driver. Combination Switch Assembly EV Switch Outputs the EV drive mode switch signal to the hybrid vehicle control ECU when operated by the driver. PWR MODE Switch Outputs the PWR MODE switch signal to the hybrid vehicle control ECU when operated by the driver. ECO MODE Switch Outputs the ECO MODE switch signal to the hybrid vehicle control ECU via the air conditioning amplifier when operated by the driver. Air Conditioning Amplifier Assembly Transmits various A/C state signals to the hybrid vehicle control ECU.

CHECK FOR INTERMITTENT PROBLEMS

  1. CHECK FOR INTERMITTENT PROBLEMS Perform a simulation test. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»(ref-398089-S18270818032011051600000) . For the simulation test, reproduce the driving conditions that were present when the trouble occurred. These conditions should be based on the customer's comments and freeze frame data that is recorded with DTCs, such as the opening angle of the accelerator pedal, SOC, engine coolant temperature, engine rpm, and MG1/MG2 rpm and torque. Check the connector(s) and terminal(s). Refer to «ELECTRONIC CIRCUIT INSPECTION PROCEDURE»(ref-398089-S40084685972011051600000) . Wiggle the harness and connector(s). Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»(ref-398089-S18270818032011051600000) . Heat or cool suspected parts. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»(ref-398089-S18270818032011051600000) .

REGISTRATION

Note. The Vehicle Identification Number (VIN) must be input into the replacement hybrid vehicle control ECU.

HINT

The VIN is a 17-digit alphanumeric vehicle identification number. The Techstream is required to register the VIN.

  1. DESCRIPTION Read VIN: This process allows the VIN stored in the hybrid vehicle control ECU to be read, in order to confirm that the two VINs, provided with the vehicle and stored in the hybrid vehicle control ECU, are the same. Write VIN: This process allows the VIN to be input into the hybrid vehicle control ECU. If the hybrid vehicle control ECU is changed, or the hybrid vehicle control ECU VIN and the vehicle VIN do not match, the VIN can be registered, or overwritten in the hybrid vehicle control ECU by following this procedure.
  2. READ VIN Confirm the vehicle VIN. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Powertrain / Hybrid Control / Utility / VIN / VIN Read.
  3. WRITE VIN Confirm the vehicle VIN. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Powertrain / Hybrid Control / Utility / VIN / VIN Write.