Honda HR-V: Description
COOLING FAN CONTROL SYSTEM DESCRIPTION - OVERVIEW
Overview
Receiving various signals, such as coolant temperature signals and refrigerant compression signals, from sensors, the PCM performs the fan control switching the fan speed (HI/LO) as needed. This control efficiently operates the radiator fan and A/C condenser fan, and improves fuel efficiency by reducing electrical load.
Fan LO Control Operation
In fan LO control, the PCM switches the FAN LO terminal to the ON position, and that switches the radiator fan relay to the ON position. Then, current flows from the 12 volt battery to the radiator fan relay, the radiator fan motor, the fan control relay and the A/C condenser fan motor, to create a series connection through the radiator fan motor and the A/C condenser fan motor. Using this series connection, the fan rotates at a lower speed.
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Fan HI Control Operation
In fan HI control, the PCM powers the FAN LO terminal and FAN HI terminal. This switches the radiator fan relay, the fan control relay, and the A/C condenser fan relay to the ON position. With the radiator fan relay and the fan control relay in the ON position, current from the 12 volt battery flows through the radiator fan relay to the radiator fan motor and then through the fan control relay to the ground. This rotates the radiator fan at a high speed. In addition, with the A/C condenser fan relay and the fan control relay in the ON position, current from the 12 volt battery flows through the A/C condenser fan relay to the A/C condenser fan motor to the ground.
This rotates the A/C condenser fan at a high speed.
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COOLING SYSTEM DESCRIPTION - COOLING CIRCUIT
Cooling System Description - Cooling Circuit
Overview
The coolant system uses a liquid cooling pressure circulation type, which is a bottom bypass system with a thermostat located at the water inlet side.
Cooling Circuit
Thermostat Closed:
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Thermostat Opened:
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Testing
POWER RELAY TEST
Special Tools Required
Relay Puller
07AAC-
000A2A1 or
07AAC-
000A1A0
Relay Socket
Extension (5 Pin)
07AGK-
000A2A0
Relay Socket
Extension (4 Pin)
07AGK-
000A1A0
Test
1. Power Relay
Check
COOLANT CHECK
Check
1. Coolant - Check
Check the coolant level in the coolant reservoir. Make sure it is
between the MAX
mark (A) and the MIN mark (B)
If the coolant level in the coolant reserv
Symptom Troubleshooting
BOTH THE RADIATOR FAN AND THE A/C CONDENSER FAN DO NOT RUN AT LOW SPEED
Diagnostic Procedure
1. Radiator and A/C Condenser Fan Low Speed Circuit Troubleshooting
Also check for
Check the connectors are
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Audio System Sound Quality Diagnosis
Special Tools Required
Diagnostic CD 07AAZ-SDBA100
Use the following tests to check sound quality.
NOTE:
Before beginning the following tests, write down the bass, the treble,
the fader and the balance settings, and then set them to their center
positions for testing.
Always verify the custom
EPS System Description - Motion Adaptive-EPS Control
Overview
Motion adaptive-EPS control performs the steering torque correction control
coordinated with VSA system for
stabilizing the vehicle when the steering is unstable. The EPS system determines
the state of the vehicle based
on the data calculated by the VSA modulator-control unit, and the dat
