DTC P0A38-257: Generator Temperature Sensor Circuit Low; DTC P0A39-259: Generator Temperature Sensor Circuit High: Procedure

WARNING: This page is about a different variant/trim than selected.

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR) See step 3
NG → CONNECT SECURELY

OK: Go to next step
CHECK CONNECTOR CONNECTION CONDITION (GENERATOR TEMPERATURE SENSOR CONNECTOR)
1. Check the connections of the generator temperature sensor connector.
  OK
  
  The connector is connected securely and there are no contact problems.
NG → CONNECT SECURELY

OK: Go to next step

READ VALUE USING TECHSTREAM (MOTOR TEMP NO2)

Turn the power switch on (IG).
Select the following menu items: Powertrain / Hybrid Control / Data List / Motor Temp No2.

Read the data list.

Result

A	B	C
-50°C (-58°F)	205°C (401°F) or more	Same as actual temperature

B → See step 6

C → See step 10

A: Go to next step

READ VALUE USING TECHSTREAM (MOTOR TEMP NO2)
1. Disconnect the C59 generator temperature sensor connector.
  
  Fig 1: Identifying C59 Generator Temperature Sensor Connector Terminal Identification
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect terminals 4 and 9 of the generator temperature sensor wire harness side connector.
3. Turn the power switch on (IG).
4. Select the following menu items: Powertrain / Hybrid Control / Data List / Motor Temp No2.
5. Read the data list.
  Displayed temperature
  
  205°C (401°F) or more
OK → See step 9

NG: Go to next step

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - GENERATOR TEMPERATURE SENSOR)

Disconnect the A61 hybrid vehicle control ECU connector.
Turn the power switch on (IG).

Measure the voltage according to the value(s) in the table below.

Fig 2: Identifying C59 Generator Temperature Sensor And A61 Hybrid Vehicle Control ECU Connector Terminal Identification

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard voltage

Tester Connection	Specified Condition
GMT (A61-99) - Body ground	Below 1 V
GMTG (A61-79) - Body ground	Below 1 V

NOTE:

Turning the power switch on (IG) with the hybrid vehicle control ECU connectors disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

Turn the power switch off.
Disconnect the generator temperature sensor connector.

Measure the resistance according to the value(s) in the table below.

Standard resistance (Check for open)

Tester Connection	Specified Condition
GMT (A61-99) - GMT (C59-4)	Below 1 Ω
GMTG (A61-79) - GMTG (C59-9)	Below 1 Ω

Standard resistance (Check for short)

Tester Connection	Specified Condition
GMT (A61-99) or GMT (C59-4) - Body ground	10 kΩ or more
GMTG (A61-79) or GMTG (C59-9) - Body ground	10 kΩ or more

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → See step 8

READ VALUE USING TECHSTREAM (MOTOR TEMP NO2)
1. Disconnect the generator temperature sensor connector.
2. Turn the power switch on (IG).
3. Select the following menu items: Powertrain / Hybrid Control / Data List / Motor Temp No2.
4. Read the data list.
  Displayed temperature
  
  -50°C (-58°F)
OK → See step 9

NG: Go to next step