DTC U0180 (F and AUTO)

DTC U0180 or DTC indicator F and AUTO : Lost communication with automatic lighting control unit/sensor

NOTE:

The DTC may be stored due to the grounding failure or the power source failure at the sunlight sensor (the grounding inspection and the power source inspection on each control unit are required prior to this checking process).

DTC Description	DTC
U0180 Lost communication with automatic lighting control unit/sensor

DTCs (AC)

Problem verification

- 1. Clear the DTC with the HDS.

- 2. Turn the vehicle to the OFF (LOCK) mode then the ON mode.

- 3. Wait for at least 6 seconds.

- 4. Do the Self-Diagnostic Function with the HDS or the climate control unit.

- 5. Check for DTCs.

DTC Description	DTC
U0180 Lost communication with automatic lighting control unit/sensor

Is DTC U0180 or F and AUTO indicated?

YES

Go to step 2.

Intermittent failure, the system is OK at this time. Check for loose wires or poor connections.

Open wire check (B-CAN_H line)

- 1. Turn the vehicle to the OFF (LOCK) mode.

- 2. Disconnect the following connectors.

Climate control unit connector A (32P)

Sunlight sensor 5P connector

- 3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Climate control unit connector A (32P): disconnected
	Sunlight sensor 5P connector: disconnected
Test point 1	Climate control unit connector A (32P) No. 23 - Refer to: Climate Control Unit Connector For Inputs and Outputs (2019 2020 2021), or Climate Control Unit Connector For Inputs and Outputs (2016 2017 2018)
Test point 2	Sunlight sensor 5P connector No. 1

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The B-CAN_H wire is OK. Go to step 3.

Repair an open in the wire between the climate control unit and the sunlight sensor.

Open wire check (B-CAN_L line)

- 1. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Climate control unit connector A (32P): disconnected
	Sunlight sensor 5P connector: disconnected
Test point 1	Climate control unit connector A (32P) No. 24 - Refer to: Climate Control Unit Connector For Inputs and Outputs (2019 2020 2021), or Climate Control Unit Connector For Inputs and Outputs (2016 2017 2018)
Test point 2	Sunlight sensor 5P connector No. 2

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The B-CAN_L wire is OK. Replace the sunlight sensor - Refer to: Sunlight Sensor Removal and Installation(Without Automatic Wiper), or Sunlight Sensor Removal and Installation(With Automatic Wiper) .

Repair an open in the wire between the climate control unit and the sunlight sensor.