DTC U0103-87: Lost Communication with Gear Shift Control Module "A" Missing Message [10/2020 - 10/2023]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG).
3. Enter the following menus: Health Check.
4. Check for DTCs.

   Result

   Result	Proceed to
   DTC P176D-12 does not output.	A
   DTC P176D-12 is output.	B

5. Turn the engine switch off.

Result: 

B 

GO TO DTC CHART (P176D-12). Refer to  DTC P176D-12: IG2 Signal (Gear Shift Control Module "A") Circuit Short to Battery [12/2017 - 10/2023] 

Result: 

A 

See step  2

1. Check the connector connections and contact pressure of the relevant terminals for the shift control ECU connectors.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [12/2017 - ]

   OK

   The connectors are connected securely and there are no contact pressure problems.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

CONNECT SECURELY 

Result: 

OK 

See step  3

1. Disconnect the G81 shift control ECU connector.
2. Disconnect the A95 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Switch Condition	Specified Condition
   G81-6(CA2H) - A95-26(CANP)	Engine switch off	Below 1 Ω
   G81-5(CA2L) - A95-25(CANN)	Engine switch off	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Switch Condition	Specified Condition
   G81-6(CA2H) or A95-26(CANP) - Body ground and other terminals	Engine switch off	10 kΩ or higher
   G81-5(CA2L) or A95-25(CANN) - Body ground and other terminals	Engine switch off	10 kΩ or higher

4. Reconnect the A95 ECM connector.
5. Reconnect the G81 shift control ECU connector.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Turn the engine switch off.
2. Check that the ODO meter display has turned off.

   HINT: 

   After turning the engine switch off, the ODO meter turns off after roughly 30 seconds and the sub-battery module assembly enters sleep mode. However, after the electrical system has been shut off when the battery (circuit) power failure is determined, approximately 12 V may be maintained between the positive (+) terminal and negative (-) terminal of the sub-battery module assembly for up to approximately 10 minutes.

3. Disconnect the cable from the negative (-) battery terminal.
4. Disconnect the G81 shift control ECU connector.
5. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G81-6(CA2H) - G81-5(CA2L)	20°C (68°F)	108 to 132 kΩ

6. Reconnect the G81 shift control ECU connector.
7. Connect the cable to the negative (-) battery terminal.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE SHIFT CONTROL ECU. Refer to  REMOVAL [10/2020 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023] 

Result: 

NG 

REPLACE ECM. Refer to  REMOVAL [10/2020 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023]