DTC Troubleshooting: B120A (8A)
Honda HRV Hybrid DTC B120A or DTC indicator 8A: Climate Control Unit LIN Communication Bus Line Error
How to use this manual
Before you troubleshoot, review the How to Troubleshoot.
■ Overview
If the climate control unit detects BUS-OFF condition in LIN continuously for a set number of times, the climate control unit determines an abnormality and stores the DTC.
■ Inspection Outline
The components to be tested are indicated by a dotted line.
Inspection Items
- a.External Circuit: IG2_A/C, GND, BUS-DATA Circuit Inspection
- b.Climate Control Switch: Climate Control Switch Inspection
- c.Climate Control Unit: Climate Control Unit Inspection
a.IG2_A/C, GND, BUS-DATA Circuit Inspection
■ Test Procedure
- Preparation
Climate control switch 8P connector: disconnected
Climate control unit connector A (24P): disconnected - Procedure
Perform the inspection according to the following table.
NOTICE:
Refer to the Open/Shorted Wire Inspection Description for the method to inspect the shorted circuit below, then start to inspect according to circumstances.
■ Results
If abnormal, there is a problem in the circuit.
NOTICE:
If the power supply inspection of the above table showed abnormally, do the additional Power Supply Inspection, to locate the failure.
b. Climate Control Switch Inspection
NOTE:
Since there is no direct method to test the inspection item, troubleshooting is performed using a known-good component.
■ Test Procedure
Install a known-good climate control switch and attempt to reproduce the failure.
■ Results
If the failure is reproduced, there is a problem with other related components.
If the symptom/DTC goes away, the climate control switch must be faulty.
c. Climate Control Unit Inspection
■ Test Procedure
If the other inspection item(s) indicated a normal condition, then it is determined that the remaining climate control unit is the cause.
■ Results
There is a problem with the climate control unit.
■ Confirmation Procedure
Turn the vehicle to the ON mode.
Component Location Index
- －Climate Control Switch, Climate Control Unit
