DTC U0199: Lost Communication with "Door Control Module A" [10/2015 - ]: Procedure

1. Reconfirm DTCs.

   HINT: 

   If DTC U1002 is output from Main Body of the main body ECU (multiplex network body ECU), this indicates a sub bus 1 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 1.

   	Proceed to
   DTC U1002 is not output from main body ECU (multiplex network body ECU) (Techstream display: Main Body)	A
   DTC U1002 is output from main body ECU (multiplex network body ECU) (Techstream display: Main Body)	B

Result: 

B 

Refer to  DTC U1002: Lost Communication with Gateway Module (Main Body ECU) [10/2015 - ]  

Result: 

A 

See step  2

1. Disconnect the cable from the negative (-) battery terminal.
2. Disconnect the F10 outer mirror control ECU assembly (front passenger door) connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Outer Mirror Control ECU Assembly (Front Passenger Door))

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   F10-9 (CANP) - F10-8 (CANN)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

Result: 

NG 

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (OUTER MIRROR CONTROL ECU ASSEMBLY (FRONT PASSENGER DOOR)) 

Result: 

OK 

See step  3

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Outer Mirror Control ECU Assembly (Front Passenger Door))

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   F10-7 (GND) - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω

2. Reconnect the cable to the negative (-) battery terminal.
3. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Outer Mirror Control ECU Assembly (Front Passenger Door))

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   F10-5 (SIG) - Body ground	Engine switch on (IG)	11 to 14 V
   F10-6 (CPUB) - Body ground	Always	11 to 14 V

Result: 

OK 

REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY (FRONT PASSENGER DOOR). Refer to  REMOVAL [10/2014 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)