Control System (Diagnostic Codes (P0A92-261 - P0BCF-312)): Overview Toyota Prius C I facelift

DESCRIPTION

For a description of generator (MG1). Refer to DESCRIPTION.

MONITOR DESCRIPTION

The MG ECU monitors generator (MG1). If the MG ECU detects a reduction in the magnetic force of generator (MG1) or an inphase short, it interprets this as an generator (MG1) failure. The power management control ECU will illuminate the MIL and set a DTC.

For a description of generator (MG1). Refer to DESCRIPTION.

Suspected malfunctioning parts

1. Open circuit in the generator coil or generator cable
2. Insecure connection of the generator cable connector
3. Inverter with converter assembly power output circuit malfunction

The MG ECU monitors generator (MG1). If the MG ECU detects a malfunction of generator (MG1), the power management control ECU will illuminate the MIL and set a DTC.

The inverter converts the high-voltage direct current of the HV battery into the alternating current for generator and motor. The inverter generates heat during the conversion process. Therefore, the inverter is cooled by a special cooling system consisting of the inverter water pump assembly, the cooling fan, and a radiator. This cooling system is independent of the engine cooling system. The power management control ECU monitors the inverter water pump assembly, cooling fan, and cooling system, and detects the following malfunctions.

Scheme 265

TEXT IN ILLUSTRATION

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. Vehicle Spd
2. Ambient Temperature
3. Total Distance Traveled

Operation History Data

1. Coolant Heating

If the power management control ECU detects a malfunction of the inverter cooling system, the ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

If the boost converter detects overvoltage, it will transmit an overvoltage signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

If excessive amperage flows through the boost converter, the boost converter will transmit a boost converter fail signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

The boost converter boosts the 144 V DC from the HV battery to a maximum of approximately 520 V DC. The inverter converts the voltage that has been boosted by the boost converter into alternating current, which is used for driving generator and motor. When a motor generator operates as a generator, the alternating current that it creates is converted into direct current by the inverter. Then the boost converter drops this voltage to direct-current of approximately 144 V in order to charge the HV battery.

Scheme 266

The MG ECU uses a voltage sensor (VL) that is built into the boost converter to detect the high voltage before it is boosted. It also uses a voltage sensor (VH) that is built into the inverter to detect the high voltage after it is boosted. Based on the voltage before and after it is boosted, the MG ECU controls the operation of the boost converter to boost the voltage to the target voltage.

HINT

With the vehicle stopped, apply the parking brake and turn the ignition switch ON (READY).

With the shift lever in P, depress the brake pedal firmly, and quickly and fully depress the accelerator pedal.

Immediately after the accelerator pedal is fully depressed, "VH-Voltage after boosting" will be between 400 and 500 V.

RELATED DATA LIST

If the difference between the requested boost converter voltage and the actual boost converter voltage exceeds a predetermined value, the MG ECU determines that there is a malfunction of the execution or monitoring in the boost converter voltage. The MG ECU will send information about the malfunction to the power management control ECU. Upon receiving this information, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

*: The MG ECU, which is built into in the inverter with converter assembly, is suspected as a main cause of the malfunction.

RELATED DATA LIST

If the boost converter detects overvoltage, it will transmit an overvoltage signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

*: Inverter with converter assembly may be suspected as a main case of the malfunction.

RELATED DATA LIST

If the boost converter detects overvoltage, it will transmit an overvoltage signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

*: Hybrid vehicle transaxle assembly may be suspected as a main case of the malfunction.

RELATED DATA LIST

If the boost converter detects overvoltage, it will transmit an overvoltage signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

RELATED DATA LIST

If the boost converter detects a circuit malfunction, it will transmit a boost converter overvoltage signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. Conv-Temp after IG-ON
2. Converter Temp Max
3. Total Distance Traveled

Operation History Data

1. Converter Heating

If the boost converter overheats, it will transmit a boost converter fail signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

*: Inverter with converter assembly may be suspected as a main case of the malfunction.

If excessive amperage flows through the boost converter due to an internal short, the boost converter will transmit a boost converter fail signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

*: Inverter with converter assembly may be suspected as a main case of the malfunction.

If excessive amperage flows through the boost converter due to an internal short, the boost converter will transmit a boost converter fail signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

*: Hybrid vehicle transaxle assembly may be suspected as a main case of the malfunction.

If excessive amperage flows through the boost converter due to an internal short, the boost converter will transmit a boost converter fail signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

If a malfunction occurs in the boost converter, the MG ECU detects it and transmits this information to the power management control ECU.

If the boost converter detects a circuit malfunction, it will transmit a boost converter fail signal to the MG ECU. Upon receiving this signal, the power management control ECU will illuminate the MIL and set a DTC.

Refer to the description for DTC P0A94-589. Refer to DESCRIPTION.

RELATED DATA LIST

The power management control ECU monitors the boost converter voltage sensor signal. If the power management control ECU detects an abnormality in the sensor signal, the power management control ECU will illuminate the MIL and set a DTC.

For a description of the boost converter. Refer to DESCRIPTION.

The MG ECU uses a voltage sensor (VL) that is built into the boost converter to detect the high voltage before it is boosted. The ECU also uses the battery smart unit to detect HV battery voltage (VB).

HINT

Using the Techstream, check the Data List of Power Resource VB and Batt Pack Current Val. If these values are not within the below range, there is a battery smart unit malfunction.

Scheme 267

RELATED DATA LIST

The power management control ECU monitors signals of HV battery voltage (VB) and boost converter voltage (VL) sensors. When a large difference occurs between the voltages from the VB and VL sensors, the power management control ECU interprets this as a failure of either of the sensors. The power management control ECU will illuminate the MIL and set a DTC.

The MG ECU uses a voltage sensor that is built into the boost converter to detect pre-boost high voltage (VL) to allow boost control. The MG ECU monitors the boost converter voltage sensor signal line and detects the following malfunctions.

RELATED DATA LIST

The MG ECU monitors the boost converter voltage (VL) sensor circuit. If the MG ECU detects an open or short circuit malfunction of the VL sensor circuit, the power management control ECU will illuminate the MIL and set a DTC.

Refer to the description for DTC P0A94-589. Refer to DESCRIPTION.

RELATED DATA LIST

The MG ECU monitors the boost converter voltage (VL) sensor circuit. If the MG ECU detects an open or short circuit malfunction of the VL sensor circuit, the power management control ECU will illuminate the MIL and set a DTC.

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. SMRP Status
2. SMRB Status
3. SMRG Status

1. Refer to the description for DTC P0AE6-225. Refer to «DESCRIPTION»(ref-651328-S18479521142014081900000).
2. This circuit uses the power management control ECU to monitor the system main relays and stops the system if a malfunction is detected in the relays, because it may be impossible to shut off the high-voltage system if any of the relays becomes stuck.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. SMRP Status
2. SMRB Status
3. SMRG Status

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. SMRP Status
2. SMRB Status
3. SMRG Status

The power management control ECU using the battery smart unit and detects insulation malfunctions in the high-voltage system.

HINT

1. *1: INF code 526 is stored together with P0AA6.
2. If DTC P0AA6 is stored, the vehicle cannot start.
3. *2: The insulation malfunction detection circuit in the battery voltage sensor monitors the insulation resistance between the high voltage circuits and body. If the insulation resistance decreases, the power management control ECU stores DTC P0AA6-526 and illuminates the MIL first.
4. *3: If the following operations are performed within the same trip after DTC P0AA6-526 is stored, just one of the related DTCs (P0AA6-611, 612, 613 or 614) will be stored. Apply the parking brake firmly. Wait for 1 minute or more with the vehicle stopped, the brake pedal firmly depressed, the ignition switch to ON (READY), the shift lever in D and the air conditioning system on (Lo/COOL MAX, blower speed HI). Then turn the ignition switch off and wait for 1 minute or more.
5. When measuring insulation resistance using a megohmmeter, measure the resistance while jiggling the high voltage wire harness.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. Vehicle Spd
2. Engine Run Time
3. +B
4. DTC Clear Run Distance
5. Ready Signal
6. State of Charge (All Bat)

Scheme 268

TEXT IN ILLUSTRATION

Scheme 269

SYSTEM DESCRIPTION

HINT

If a decrease in insulation resistance cannot be confirmed using a megohmmeter, check the Short Wave Highest Val in the Data List.

1. SHORT WAVE HIGHEST VALUE "Short Wave Highest Val" indicates a decrease in insulation resistance and decreases the value as the insulation resistance decreases. In some cases, "Short Wave Highest Val" may decrease even though the insulation resistance of the vehicle is normal, therefore avoid checking "Short Wave Highest Val" when any of the following conditions exist. Within approximately 1 minute has passed since the ignition switch was turned on (IG). There is change of the system voltages ("Power Resource VB", "VL-Voltage before Boosting", and "VH-Voltage after Boosting"). During boosting, the Data List item "Boost Ratio" is not 0% or within a few seconds of it returned to 0%. (The values of "Power Resource VB", "VL-Voltage before Boosting" and "VHVoltage after Boosting" are about the same when not boosting.) When "Short Wave Highest Val" is approximately 0 V, insulation resistance is close to 0 ohms. In this case, damage to a high-voltage cable or hybrid component (high-voltage), or a short to the body due to intrusion of foreign matter such as metal particles can be suspected.
2. RELATED FREEZE FRAME DATA If problem symptoms cannot be duplicated and a malfunction still exists after replacing a part as instructed, checking the following freeze frame data can help determine a trouble area. Freeze Frame Data Diagnostic Note Short Wave Highest Val Indicates that the insulation resistance has decreased. VL-Voltage before Boosting VH-Voltage after Boosting Power Resource VB Boost Ratio During boosting (when "Boost Ratio" is not 0%), or when "VL-Voltage before Boosting", "VH-Voltage after Boosting" or "Power Resource VB" is varying, "Short Wave Highest Val" may decrease even though the insulation resistance is normal. SMRP Status SMRB Status SMRG Status When "SMRP Status", "SMRB Status" and "SMRG Status" are all OFF, the insulation malfunction detection circuit detects a decrease in insulation resistance in the HV battery area ((*d) in the wiring diagram). Example: When the ignition switch is turned on (IG) (not on (READY)), all 3 system main relays are off and it is suspected that the HV battery assembly is disconnected from the high voltage circuits. If "Short Wave Highest Val" decreases a few minutes after the ignition switch is turned on (IG) (not on (READY)), the HV battery assembly may have an insulation malfunction. MG2 Gate Status When "MG2 Gate Status" is ON, the insulation malfunction detection circuit cannot detect a decrease in insulation resistance in the motor system AC (alternating current) section (motor (MG2) side of (*e) in the wiring diagram). The motor system AC (alternating current) section includes the motor (MG2) in the hybrid vehicle transmission assembly, motor cables and the AC (alternating current) section of the motor drive circuit in the inverter with converter assembly. MG1 Gate Status When "MG1 Gate Status" is ON, the insulation malfunction detection circuit cannot detect a decrease in insulation resistance in the generator system AC (alternating current) section (generator (MG1) side of (*e) in the wiring diagram). The generator system AC (alternating current) section includes the generator (MG1) in the hybrid vehicle transmission assembly, generator cables and the AC (alternating current) section of the generator drive circuit in the inverter with converter assembly. A/C Consumption Pwr When the air conditioning system is off (air conditioning system power consumption is 0 W), the insulation malfunction detection circuit cannot detect a decrease in insulation resistance in the compressor with motor assembly AC (alternating current) section ((*c) in the wiring diagram). The compressor with motor assembly AC (alternating current) section includes the air conditioning motor, wiring between the air conditioning motor and air conditioning inverter, and the AC (alternating current) section of the air conditioning motor drive circuit in the air conditioning inverter. With the vehicle stopped, turn on/off the air conditioning system and observe "Short Wave Highest Val" to use as a diagnosis reference. HINT: Items to be checked using the freeze frame data. Reproducing the vehicle conditions the moment a DTC was stored according to the freeze frame data and results of the customer problem analysis helps ensure that the same DTC is stored again. DRIVING STATUS Item Diagnostic Note Vehicle Spd - Accel Pedal Pos #1 - Engine Revolution - Shift Sensor Shift Pos - Master Cylinder Ctrl Trq - Engine Coolant Temp - OPERATION CONDITIONS Item Diagnostic Note Motor Temp No1 If any liquid leaks into the ATF, insulation resistance may decrease only when the temperature is high. The motor temperature is likely to increase if the motor speed is low and output torque is high such as when cruising uphill slowly or accelerating from a low speed. Motor Temp No2 If any liquid leaks into the ATF, insulation resistance may decrease only when the temperature is high. The generator temperature is likely to increase under repeat acceleration and deceleration while the vehicle is driven in the mid speed range (60 to 80 km/h (37 to 50 mph)). Customer Problem Analysis Ask the customer about the operating conditions and environment when the malfunction occurred. Item Diagnostic Note Driving Condition (acceleration, deceleration, turning, etc.) Changes in the insulation of the parts with insufficient insulation due to changes in G force or vibration is suspected. Road Condition (unpaved, etc.) Weather (rain, snow, etc.) Water intrusion is suspected Washing the vehicle (Whether the malfunction occurred after washing the vehicle?)
3. CONFIRMATION AFTER REPLACING PARTS After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output. (Do not turn the ignition switch off (READY off) during this inspection.) Apply the parking brake and secure the wheels using chocks. When the vehicle is stationary, turn the ignition switch to ON (READY) with the shift lever in P and wait for 60 seconds or more. Turn the air conditioning system on (MAX COLD, blower speed HI). While depressing the brake pedal without depressing the accelerator pedal, move the shift lever to D and wait for 5 minutes. If step (*) is performed within the same trip after DTC P0AA6-526 is stored, the parts with insufficient insulation resistance will be determined, and DTC one of the P0AA6-611, 612, 613 or 614 will be stored. (If no DTCs are output, proceed to the next step.) Drive the vehicle for approximately 5 minutes referring to the following freeze frame data items: "Vehicle Spd", "Shift Sensor Shift Pos", "Accel Pedal Pos #1", "Engine Revolution", "Engine Coolant Temp" and "Master Cylinder Ctrl Trq". (If the freeze frame data item "Vehicle Spd" is 10 km/h (6 mph) or less, drive the vehicle at 10 (6 mph) km/h or more.) If step (*) is performed within the same trip after DTC P0AA6-526 is stored, the parts with insufficient insulation resistance will be determined, and DTC one of the P0AA6-611, 612, 613 or 614 will be stored. If no DTCs ore output, insulation fault does not detected. Wait for 1 minute or more with the vehicle stopped, the ignition switch to ON (READY), the shift lever in P and the air conditioning system on (Lo/COOL MAX, blower speed HI), then turn the ignition switch off and wait for 1 minute or more. (*) HINT: If the DTC is not output again, check for driving conditions that would cause the Data List item "Short Wave Highest Val" to decrease.

The power management control ECU monitors the insulation monitoring circuit located in the battery smart unit and detects a malfunction.

RELATED DATA LIST

The power management control ECU detects malfunctions of the battery current sensor by monitoring MG1 and MG2 torque. If the power management control ECU detects a battery current sensor malfunction, the power management control ECU will illuminate the MIL and set a DTC.

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. SMRP Status
2. SMRB Status
3. SMRG Status
4. SMRP Control Status
5. SMRB Control Status
6. SMRG Control Status

The SMRs (System Main Relays) are the relays that connect or disconnect the high voltage power system in accordance with commands from the power management control ECU.

There are 3 SMRs and 1 precharge resistor. SMRB, SMRP, SMRG, and the precharge resistor are located in the hybrid battery junction block assembly in the HV battery pack.

To connect to the high voltage power system, the vehicle will first turn on SMRP and SMRB to charge the vehicle through the system main resistor. Then, SMRP will be turned off after SMRG is turned on. To shut off the high voltage power system, SMRB and SMRG are turned off.

RELATED DATA LIST

Scheme 270

Scheme 271

Refer to the description for DTC P0AE6-225. Refer to DESCRIPTION.

RELATED DATA LIST

The MG ECU located in the inverter with converter assembly detects the temperature of the motor inverter using the temperature sensor built into the motor inverter. If necessary, the MG ECU will limit inverter output to help prevent motor inverter overheating. The power management control ECU also detects malfunctions in the sensor based on the temperature sensor values. The inverter with converter assembly detects malfunctions in the motor inverter temperature sensor and its wiring.

HINT

*: If only DTC P0AF1-276 is output, a temperature sensor malfunction is more likely to be the cause than a sudden change in actual temperature.

RELATED DATA LIST

1. The MG ECU located in the inverter with converter assembly detects the temperature of the motor inverter using a temperature sensor built into the inverter with converter assembly. The inverter cooling system operates independently of the engine cooling system. The MG ECU uses signals from the motor inverter temperature sensor to check the effectiveness of the inverter cooling system. If necessary, the MG ECU will limit inverter output to help prevent inverter overheating. The MG ECU also detects malfunctions in the motor inverter temperature sensor and its wiring.

RELATED DATA LIST

The battery smart unit (battery energy control module) sends HV battery voltage information to the power management control ECU via serial communication.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. Ready Signal

The power management control ECU calculates the differences between the received HV battery voltage, boost converter voltage, and inverter voltage. If the differences exceed prescribed values, the power management control ECU determines that there is a malfunction in the battery smart unit circuit. When the power management control ECU detects this malfunction, it will illuminate the MIL and set a DTC.

The power management control ECU alerts the driver and performs fail-safe control based on error signals sent from the battery smart unit.

RELATED DATA LIST

When the power management control ECU detects a low power supply voltage for the battery smart unit while pre-charge is occurring, it determines that there is a malfunction in the battery smart unit circuit. When the power management control ECU detects a malfunction, it will illuminate the MIL and set a DTC.

The MG ECU located in the inverter with converter assembly detects the temperature of the generator inverter using the temperature sensor built into the generator inverter. If necessary, the MG ECU will limit inverter output to help prevent generator inverter overheating. The power management control ECU also detects malfunctions in the sensor based on the temperature sensor values. The inverter with converter assembly detects malfunctions in the generator inverter temperature sensor and its wiring.

HINT

*: If only DTC P0BD0-314 is output, a temperature sensor malfunction is more likely to be the cause than a sudden change in actual temperature.

RELATED DATA LIST

The following items can be helpful when performing repairs

Data List

1. Total Distance Traveled

Operation History Data

1. MG1 (Generator) Inverter Temperature High

1. The MG ECU located in the inverter with converter assembly detects the temperature of the generator inverter using the temperature sensor built into the inverter with converter assembly. The inverter cooling system operates independently of the engine cooling system. The MG ECU uses signals from the generator inverter temperature sensor to check the effectiveness of the inverter cooling system. If necessary, the MG ECU will limit inverter output to help prevent inverter overheating. The ECU also detects malfunctions in the generator inverter temperature sensor and its wiring.

RELATED DATA LIST

See also:
• COMPONENTS [12/2013 - ]
• REMOVAL [12/2013 - ] - Step 7