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Hybrid Battery System (Diagnostics - Introduction): Other Lexus HS I

Engine Control Systems 12 illustrations ~1136 words

DEFINITION OF TERMS

TermsDefinition
Monitor DescriptionDescription of what the hybrid vehicle control ECU monitors and how to 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.

Scheme 585

Scheme 585: ILLUSTRATION

Scheme 586

Scheme 586: ILLUSTRATION

Scheme 587

Scheme 587: SYSTEM DIAGRAM

Scheme 588

Scheme 588

Scheme 589

Scheme 589

Scheme 590

Scheme 590: SYSTEM DESCRIPTION
  1. BATTERY SMART UNIT CONTROL The battery smart unit converts the HV battery condition signals (voltage, current, and temperature), which are needed to determine the charging or discharging values that are calculated by the hybrid vehicle control ECU into digital signals, and transmits them to the hybrid vehicle control ECU via serial communication. A leakage detection circuit is provided in the battery smart unit in order to detect any leakage from the HV battery. Furthermore, the battery smart unit detects the voltage of the cooling fan, which is needed by the hybrid vehicle control ECU to effect cooling fan control. The battery smart unit also converts these signals into digital signals and transmits them to the hybrid vehicle control ECU via serial communication.

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) .

Scheme 591

Scheme 591: TERMINALS OF ECU
*1Battery Smart Unit

TEXT IN ILLUSTRATION

Terminal No. (Symbol)Wiring ColorTerminal DescriptionConditionStandard (V)
Z37-4 (TB3) - z37-14 (GB3)L - LBattery temperature sensor 3HV battery temperature: -40 to 90°C (-40 to 194°F)4.8 (-40°C(-40°F)) to 1.0 (90°C(194°F))
Z37-5 (TB2) - z37-15 (GB2)B - BBattery temperature sensor 2HV battery temperature: -40 to 90°C (-40 to 194°F)4.8 (-40°C(-40°F)) to 1.0 (90°C(194°F))
Z37-6 (TB1) - z37-16 (GB1)W - WBattery temperature sensor 1HV battery temperature: -40 to 90°C (-40 to 194°F)4.8 (-40°C(-40°F)) to 1.0 (90°C(194°F))
Z37-7 (TB0) - z37-17 (GB0)R - RBattery temperature sensor 0HV battery temperature: -40 to 90°C (-40 to 194°F)4.8 (-40°C(-40°F)) to 1.0 (90°C(194°F))
Z37-9 (IB) - z37-20 (GIB)Y - BCurrent sensorPower switch on (READY)0.5 to 4.5
Z37-10 (VIB) - z37-20 (GIB)BR - BPower source for battery current sensorPower switch on (IG)4.5 to 5.5
Z15-4 (IGCT) - z15-5 (GND)L - W-BControl signalPower switch on (READY)11 to 14
Z15-2 (BTH+) - z15-5 (GND)R - W-BSerial communicationPower switch on (IG)Pulse generation (Scheme 592)
Z15-3 (BTH-) - z15-5 (GND)G - W-BSerial communicationPower switch on (IG)Pulse generation (waveform 2)
Z15-4 (IDH) - z15-5 (GND)P - W-BHybrid Vehicle Converter Cooling Fan SignalPower switch on (IG)Pulse generation (waveform 3)
Z15-7 (VM) - z15-5 (GND)B - W-BBattery cooling blower No. 0 monitor signalCooling blower activated0 to 5
Z15-5 (GND) - Body groundW-BGroundAlways (continuity check)Below 1 ohms

ECU TERMINAL CHART

Scheme 592

Scheme 592

Scheme 593

Scheme 593

Scheme 594

Scheme 594
  1. Oscilloscope waveforms HINT: Oscilloscope waveform samples are provided here for informational purposes. Noise and fluttering waveforms have been omitted. Waveform 1 Item Content Terminal z15-2 (BTH+) - z15-8 (GND) Equipment Setting 2 V/DIV., 500 μs./DIV. Condition Power switch on (IG) HINT: The waveform will vary depending on the content of the digital communication (digital signal). Waveform 2 Item Content Terminal z15-3 (BTH-) - z15-8 (GND) Equipment Setting 2 V/DIV., 500 μs./DIV. Condition Power switch on (IG) HINT: The waveform will vary depending on the content of the digital communication (digital signal). Waveform 3 Item Content Terminal z15-4 (IDH) - z15-5 (GND) Equipment Setting 2 V/DIV, 2ms/DIV Condition Power switch on (IG) HINT: The frequency of the waveform differs according to operation conditions of the cooling fan of the hybrid vehicle converter.

Scheme 595

Scheme 595: DIAGNOSIS SYSTEM

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Scheme 596
  1. DESCRIPTION The hybrid vehicle control ECU has a self-diagnosis system. If the computer, hybrid vehicle control ECU, or a component is not working properly, the ECU records the conditions that relate to the fault. The ECU also illuminates the master warning light in the combination meter and provides other appropriate messages on the multi-information display, such as the HV system warning message, the HV battery warning message, or the discharge warning message. HINT: The master warning light will illuminate when the hybrid control system malfunctions and the light will blink when in inspection mode. When troubleshooting OBD II (On-Board Diagnostics) vehicles, the Techstream (complying with SAE J1987) must be connected to the DLC3 (Data Link Connector 3) of the vehicle. Various data in the hybrid vehicle control ECU can then be read. OBD II regulations require that the vehicle's on-board computer illuminate the MIL (Malfunction Indicator Lamp) on the instrument panel when the computer detects a malfunction in: The emission control system components. The powertrain control components (which affect vehicle emissions). The computer itself. In addition, the applicable DTCs prescribed by SAE J2012 are recorded in the hybrid vehicle control ECU memory. If the malfunction does not recur in 3 consecutive trips, the MIL turns off automatically but the DTCs remain recorded in the hybrid vehicle control ECU memory. To check for DTCs, connect the Techstream to the DLC3. The Techstream displays DTCs, freeze frame data, and a variety of hybrid control system data. The DTCs and freeze frame data can be cleared with the Techstream. In order to enhance the OBD function on vehicles and develop the Off-Board diagnosis system, Controller Area Network (CAN) communication is used in this system. CAN is a network which uses a pair of data transmission lines spanning multiple computers and sensors. It allows for high speed communications between the systems and simplification of the wire harness connections.
  2. 2 TRIP DETECTION LOGIC When a malfunction is first detected, the malfunction is temporarily stored in the hybrid vehicle control ECU memory (1st trip). If the same malfunction is detected during the next drive cycle, the MIL is illuminated (2nd trip).
  3. FREEZE FRAME DATA The hybrid vehicle control ECU records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, as well as other data recorded at the time of a malfunction.
  4. AUXILIARY BATTERY VOLTAGE Standard Voltage Switch Condition Specified Condition Power switch on (IG) 11 to 14 V If voltage is below 11 V, replace or recharge the battery.
  5. MIL (Malfunction Indicator Lamp) The MIL is illuminated when the power switch is first turned on (IG), before the READY indicator comes on. When the READY indicator turns on, the MIL should turn off. If the MIL remains illuminated, the diagnosis system has detected a malfunction or abnormality in the system. HINT: If the MIL is not illuminated when the power switch is first turned on (IG), check the MIL circuit. Refer to «MIL Circuit»(ref-398226-S22188282202011051600000) .

FREEZE FRAME DATA

  1. FREEZE FRAME DATA HINT: The hybrid vehicle control ECU records vehicle and driving condition information as freeze frame data the moment a DTC is stored. It can be used for estimating or duplicating the vehicle conditions that were present when the malfunction occurred. To confirm the details of the hybrid control system, check the detailed information for the DTC information code in the data list (INF code). Connect the Techstream to the DLC3. Turn the power switch on (IG) and turn the Techstream on. Select the following menu items: Powertrain / Hybrid Control / Trouble Codes. Select a DTC in order to display its freeze frame data. Check the freeze frame data of the DTC that has been detected. Check the freeze frame information recorded with the DTC. HINT: For the freeze frame data chart. Refer to «INFORMATION / FREEZE FRAME DATA»(ref-398238-S10844569612011051600000) .
  2. INFORMATION HINT: Similar to freeze frame data, the hybrid vehicle control ECU also records vehicle and driving condition information as INFORMATION (INF code) at the moment a DTC is stored. Select the information item which has an INF code from among INFORMATION 1 to 5. Check the information for the DTC. HINT: For the freeze frame data chart. Refer to «INFORMATION / FREEZE FRAME DATA»(ref-398238-S10844569612011051600000) .