Honda HR-V: A/C Signal Circuit Troubleshooting (KA)

NOTE:

• Do not use this troubleshooting procedure if any of the following items are operative with the A/C button and the fan control dial ON: The A/C condenser fan, the radiator fan, or the A/C compressor. Refer to the symptom troubleshooting index - Refer to: Heating and A/C Systems Symptom Troubleshooting Index (Heating/Air Conditioning), or Climate Control System Symptom Troubleshooting Index (Climate Control).
• Do not use this troubleshooting procedure if the A/C system pressure is abnormal.
• Do not use this troubleshooting procedure if the blower motor does not run.
• Before doing symptom troubleshooting, check for PGM-FI DTCs - Refer to: How to Troubleshoot the Fuel and Emissions Systems, or How to Troubleshoot the CVT System (CVT).

1. PGM-FI system parameter check:

1. Connect the HDS to the DLC.
2. Start the engine.
3. Set the A/C button and the heater fan switch to ON.
4. Check the parameter(s) below with the HDS.

Do the current condition(s) match the threshold?

YES

Go to the A/C compressor clutch circuit troubleshooting - Refer to: A/C Compressor Clutch Circuit Troubleshooting (KA/KC), or A/C Compressor Clutch Circuit Troubleshooting (KA/KX).

NO

A/C SWITCH is OFF, go to step 4.

NO

A/C SWITCH is ON and A/C CLUTCH is OFF, go to step 2.

2. A/C pressure sensor performance check:

Check the parameter(s) below with the HDS.

Do the current condition(s) match the threshold?

YES

Go to step 3.

NO

Go to A/C system test.

3. Evaporator temperature sensor check:

1. Turn the vehicle to the OFF (LOCK) mode.
2. Test the evaporator temperature sensor.

Is the evaporator temperature sensor OK?

YES

Update the PCM if it does not have the latest software, or substitute a known-good PCM, and recheck.

NO

Replace the evaporator temperature sensor.

4. Heater fan switch check:

1. Turn the vehicle to the OFF (LOCK) mode.
2. Test the heater fan switch.

Is the heater fan switch OK?

YES

Go to step 5.

NO

Replace the heater fan switch.

5. Determine possible failure area (ACS line, A/C SW- line):

1. Turn the vehicle to the ON mode.
2. Measure the voltage between test points 1 and 2.

Is there battery voltage?

YES

Go to step 7.

NO

Go to step 6.

6. Open wire check (A/C SW- line):

Measure the voltage between test points 1 and 2.

Is there battery voltage?

YES

Replace the HVAC control unit.

NO

Repair an open in the wire between the heater fan switch and the HVAC control unit.

7. Open wire check (ACS line):

1. Turn the vehicle to the OFF (LOCK) mode.
2. Disconnect the following connector.

HVAC control unit 16P connector

3. Turn the vehicle to the ON mode.
4. Measure the voltage between test points 1 and 2.

Is there battery voltage?

YES

Replace the HVAC control unit.

NO

Go to step 8.

8. Open wire check (ACS line):

Measure the voltage between test points 1 and 2.

Is there battery voltage?

YES

Repair an open in the wire between the MICU and the HVAC control unit.

NO

Replace the under-dash fuse/relay box

READ NEXT: