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: Identifying Transmission Control ECU Assembly & Waveform Graph

   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 connector A24 from the transmission control ECU assembly.
2. Disconnect connector A22 from the power management control ECU.
3. Measure the resistance according to the value(s) in the table below.
   Fig 2: Checking Harness And Connector (Transmission Control ECU - Power Management Control ECU)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance (Check for Open)

   Tester Connection	Switch Condition	Specified Condition
   A24-22 (PCON) - A22-22 (PCON)	Power switch off	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Switch Condition	Specified Condition
   A24-22 (PCON) or A22-22 (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 power management control ECU connector.
5. Connect the transmission control ECU assembly connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4