DTC U0182: Lost Communication with Lighting Control Module Front [11/2017 - 03/2019]: Procedure

1. Reconfirm DTCs.

   Body Electrical > Main Body > Trouble Codes 

   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.

   Result

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

Result: 

B 

GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC. Refer to  DTC U1002: Lost Communication with Gateway Module (Main Body ECU) [11/2017 - 03/2019] 

Result: 

A 

See step  2

1. Disconnect the cable from the negative (-) battery terminal.
2. Disconnect the A3 headlight light control ECU sub-assembly LH connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Headlight Light Control ECU Sub-assembly LH)

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A3-24 (CANH) - A3-23 (CANL)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

   Result

   Result
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH) 

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 Headlight Light Control ECU Sub-assembly LH)

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A3-12 (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 Headlight Light Control ECU Sub-assembly LH)

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A3-4 (IG) - Body ground	Engine switch on (IG)	11 to 14 V
   A3-13 (ECUB) - Body ground	Engine switch on (IG)	11 to 14 V

   Result

   Result
   OK
   NG

Result: 

OK 

REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [09/2014 - 03/2019] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)