P0A39

P112 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A38-257: Generator Temperature Sensor Circuit Low

DTC P0A38-257 - Generator Temperature Sensor Circuit Low

DTC P0A39-259 - Generator Temperature Sensor Circuit High

DESCRIPTION

The No. 2 motor temperature sensor detects the temperature of the transaxle fluid. The resistance of the thermistor installed in the No. 2 motor temperature sensor varies with the changes in the transaxle fluid temperature. The construction in the No. 2 motor temperature sensor and how it is connected to the HV control ECU are the same as those of the No. 1 motor temperature sensor P0A2C.





The resistance of the thermistor, which is enclosed in the No. 1 motor temperature sensor, changes in accordance with the changes in the temperature of the motor. The lower the motor temperature, the higher the resistance of the thermistor. Conversely, the higher the temperature, the lower the resistance.
The No. 1 motor temperature sensor is connected to the HV control ECU. The power voltage of 5 V is supplied from the MMT terminal of the HV control ECU to the No. 1 motor temperature sensor via resistor R. Because resistor R and the No. 1 motor temperature sensor are connected in series, the resistance changes with the changes in temperature of the motor, which causes the MMT terminal voltage to also change.
Based on this signal, the HV control ECU limits the load in order to prevent the motor from overheating. Furthermore, the HV control ECU checks the No. 1 motor temperature sensor for a wiring malfunction and the sensor for a malfunction.

Based on the signal provided by the No. 2 motor temperature sensor, the HV control ECU limits the load to prevent the motor from overheating. Furthermore, the HV control ECU checks the No. 2 motor temperature sensor for a wiring malfunction and the sensor for a malfunction.





HINT: After confirming DTC P0A38 (INF 257) or P0A39 (INF 259), confirm Motor Temp No2 in DIAGNOSIS / OBD/MOBD / HV ECU / DATA LIST using the Techstream.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING THE TECHSTREAM (MOTOR TEMP NO2)
(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 "Motor Temp No2" value.
Result:





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

C -- CHECK FOR INTERMITTENT PROBLEMS
B -- READ VALUE USING THE TECHSTREAM (CHECK FOR GND SHORT IN WIRE HARNESS)
A -- Continue to next step.

2. INSPECT HYBRID VEHICLE MOTOR ASSEMBLY (CHECK FOR OPEN OR +B SHORT)




(a) Disconnect the M10 No. 2 motor temperature sensor connector.
(b) Turn the power switch ON (IG).




(c) Measure the voltage between the terminals of the No. 2 motor temperature sensor connector.
Result:





HINT: The No. 2 motor temperature sensor is unavailable as an individual service part. Therefore, when replacing it, the hybrid vehicle motor must be replaced.
(d) Reconnect the No. 2 motor temperature sensor connector.
C -- READ VALUE USING THE TECHSTREAM (CHECK FOR OPEN IN HYBRID VEHICLE CONTROL ECU)
A -- REPLACE HYBRID VEHICLE MOTOR ASSEMBLY
B -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (CHECK FOR +B SHORT)




(a) Disconnect the H17 HV control ECU connector.




(b) Disconnect the M10 No. 2 motor temperature sensor connector.
(c) Turn the power switch ON (IG).
(d) Measure the voltage between the terminal of the No. 2 motor temperature sensor connector and body ground.
Standard voltage:





(e) Reconnect the HV control ECU connector.
(f) Reconnect the No. 2 motor temperature sensor connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE HYBRID VEHICLE CONTROL ECU
4. READ VALUE USING THE TECHSTREAM (CHECK FOR OPEN IN HYBRID VEHICLE CONTROL ECU)




(a) Disconnect the M10 No. 2 motor temperature sensor connector.




(b) Connect terminals OMT and OMTG of the H17 HV control ECU connector.
(c) Turn the power switch ON (IG).
(d) Enter the following menus: Powertrain / Engine Control / Data List.
(e) Read the "Motor Temp No2" value.
OK:
401°F (205°C)
HINT: If the Techstream indicates a temperature of -58°F (-50°C), check the connection of the HV control ECU. If it is connected normally, replace the HV control ECU.
(f) Reconnect the No. 2 motor temperature sensor connector.
NG -- REPLACE HYBRID VEHICLE CONTROL ECU
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR
5. READ VALUE USING THE TECHSTREAM (CHECK FOR GND SHORT IN WIRE HARNESS)




(a) Disconnect the M10 No. 2 motor temperature sensor connector.
(b) Turn the power switch ON (IG).
(c) Enter the following menus: Powertrain / Engine Control / Data List.
(d) Read the "Motor Temp No2" value.
OK:
-58°F (-50°C)
(e) Reconnect the No. 2 motor temperature sensor connector.
HINT: The No. 2 motor temperature sensor is unavailable as an individual service part. Therefore, when replacing it, the hybrid vehicle motor must be replaced.

OK -- REPLACE HYBRID VEHICLE MOTOR ASSEMBLY
NG -- Continue to next step.

6. READ VALUE USING THE TECHSTREAM (CHECK FOR GND SHORT IN HYBRID VEHICLE CONTROL ECU)




(a) Disconnect the H17 HV control ECU connector.
(b) Turn the power switch ON (IG).




(c) Enter the following menus: Powertrain / Engine Control / Data List.
(d) Read the "Motor Temp No2" value.
OK:
-58°F (-50°C)
(e) Reconnect the HV control ECU connector.
NG -- REPLACE HYBRID VEHICLE CONTROL ECU
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR