DTC C2311: Communication Error from HV ECU: Procedure

1. Turn the power switch on (IG).
2. Connect an oscilloscope between the transmission control ECU assembly terminals specified in the table below, and measure the waveform.
   Fig 1: Checking A24 Connector Terminals & Waveform

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Item	Contents
   Symbols	A24-22 (PCON) - A24-1 (E1)
   Tool setting	10 V/DIV., 10 msec./DIV.
   Vehicle condition	Power switch on (IG)

   OK

   The waveform is similar to that shown in the illustration.

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Transmission Control ECU Assembly)
   *b	Waveform

   HINT: 

   Perform this inspection with the connector connected.

3. Turn the power switch off.

NG → See step   2 

OK → See step   3 

1. Disconnect the A24 transmission control ECU assembly connector.
2. Disconnect the A86 power management control ECU connector.
3. Measure the resistance according to the value(s) in the table below.
   Fig 2: Checking A24 & A86 Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   A24-22 (PCON) - A86-22 (PCON)	Power switch off	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   A24-22 (PCON) or A86-22 (PCON) - Body ground and other terminals	Power switch off	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Transmission Control ECU Assembly)
   *b	Rear view of wire harness connector (to Power Management Control ECU)

4. Connect the A86 power management control ECU connector.
5. Connect the A24 transmission control ECU assembly connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4