P0AEF

P112 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0AEF-275: Drive Motor Inverter Temperature Sensor "A" Circuit Low

DTC P0AEF-275 - Drive Motor Inverter Temperature Sensor "A" Circuit Low

DTC P0AF0-274 - Drive Motor Inverter Temperature Sensor "A" Circuit High

DESCRIPTION

The HV control ECU uses a temperature sensor, which is built into the inverter, to detect the temperature of the motor inverter. The same cooling system that is routed to the MG1 and MG2 cools the inverter. This cooling system is independent from the engine cooling system.
The characteristic of the motor inverter temperature sensor is the same as the boost converter temperature sensor P0A94.

The boost converter contains a booster IPM (Intelligent Power Module), which includes an IGBT (Insulated Gate Bipolar Transistor) and a reactor. The HV control ECU actuates the IGBT, which controls the current in the reactor.
The boost converter boosts the high-voltage direct current rated at 201.6 V to an approximate direct current voltage of 500 V. The inverter converts the voltage that has been boosted by the boost converter into alternating current, which is used for driving the MG1/MG2. When the MG1/MG2 operates as a generator, the alternating current of approximately 500 V from the MG1/MG2 is converted into direct current by the inverter.
Then, the boost converter drops this voltage to a direct current voltage rated at 201.6 V in order to charge the HV battery.





The HV control ECU uses a voltage sensor that is built into the boost converter to detect the high voltage (VL) before it is boosted. Also, it uses a voltage sensor that is built into the inverter to detect the high voltage (VH) after it has been boosted.
Based on the voltage before and after it has been boosted, the HV control ECU boosts it to a target voltage by controlling the operation of the boost converter.

The HV control ECU limits the load based on the signals transmitted by the motor inverter temperature sensor, in order to check the effectiveness of the inverter cooling system and prevent the inverter from overheating. Furthermore, the HV control ECU detects a malfunction in the wiring of the motor inverter temperature sensor, as well as in the sensor itself.





HINT: After confirming DTC P0AEF (INF 275) or P0AF0 (INF 274), confirm Inverter Temp-(MG2) in DIAGNOSIS / OBD/MOBD / HV ECU / DATA LIST using the Techstream.





WIRING DIAGRAM





INSPECTION PROCEDURE
CAUTION:
- Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are servicing the high-voltage system.
- After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals.
HINT: At least 5 minutes are required to discharge the high-voltage condenser inside the inverter.

PROCEDURE

1. READ VALUE USING THE TECHSTREAM (INVERTER TEMP-(MG2))
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch ON (IG).
(c) Enter the following menus: Powertrain / Engine Control / Data List.
(d) Read the "Inverter Temp-(MG2") value.
Result:





HINT:
- If there is a +B short circuit, the Techstream indicates -58°F (-50°C).
- If there is an open or GND short circuit, the Techstream indicates 401°F (205°C).

C -- CHECK FOR INTERMITTENT PROBLEMS
B -- CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - INVERTER)
A -- Continue to next step.

2. READ VALUE USING THE TECHSTREAM (CHECK FOR +B SHORT IN WIRE HARNESS)
CAUTION: Wear insulated gloves before performing the following operation.
(a) Turn the power switch OFF.
(b) Remove the service plug grip Removal.
NOTE: Turning the power switch ON (READY) with the service plug grip removed could cause malfunction. Therefore, never turn the power switch ON (READY) in this state.
(c) Remove the inverter cover Removal.




(d) Disconnect the I10 inverter connector.




(e) Turn the power switch ON (IG).
HINT: DTCs for the interlock switch system are output when turning the power switch ON (IG) with both service plug grip and inverter cover removed.
(f) Enter the following menus: Powertrain / Engine Control / Data List.
(g) Read the "Inverter Temp-(MG2)" value.
OK:
401°F (205°C)
(h) Turn the power switch OFF.
(i) Reconnect the inverter connector.
(j) Reinstall the inverter cover Installation.
(k) Reinstall the service plug grip Installation.
OK -- REPLACE INVERTER WITH CONVERTER ASSEMBLY
NG -- Continue to next step.

3. READ VALUE USING THE TECHSTREAM (CHECK FOR +B SHORT IN HYBRID VEHICLE CONTROL ECU)




(a) Disconnect the H15 HV control ECU connector.




(b) Turn the power switch ON (IG).
HINT: DTCs for the interlock switch system are output when turning the power switch ON (IG) with both service plug grip and inverter cover removed.
(c) Enter the following menus: Powertrain / Engine Control / Data List.
(d) Read the "Inverter Temp-(MG2)" value.
OK:
401°F (205°C)
(e) Reconnect the HV control ECU connector.
NG -- REPLACE HYBRID VEHICLE CONTROL ECU
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR
4. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - INVERTER)
CAUTION: Wear insulated gloves before performing the following operation.
(a) Turn the power switch OFF.
(b) Remove the service plug grip Removal.
NOTE: Turning the power switch ON (READY) with the service plug grip removed could cause malfunction. Therefore, never turn the power switch ON (READY) in this state.
(c) Remove the inverter cover Removal.




(d) Disconnect the H15 HV control ECU connector.




(e) Disconnect the I10 inverter connector.
(f) Measure the resistance between the wire harness side connectors.
Standard resistance (Check for open):






Standard resistance (Check for short)






(g) Reconnect the inverter connector.
(h) Reconnect the HV control ECU connector.
(i) Reinstall the inverter cover Installation.
(j) Reinstall the service plug grip Installation.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. INSPECT HYBRID VEHICLE CONTROL ECU (MIVT VOLTAGE)




(a) Turn the power switch ON (IG).
HINT: DTCs for the interlock switch system are output when turning the power switch ON (IG) with both service plug grip and inverter cover removed.
(b) Measure the voltage between the terminals of the H15 HV control ECU connector.
Standard voltage:






NG -- REPLACE INVERTER WITH CONVERTER ASSEMBLY
OK -- REPLACE HYBRID VEHICLE CONTROL ECU