Honda Civic. Manual — part 376

2006-08 ENGINE

Fan Controls (K20Z3) - Civic (All Except Si)

COMPONENT LOCATION INDEX

Fig. 1: Identifying A/C Condenser Fan Relay And Radiator Fan Relay
Courtesy of AMERICAN HONDA MOTOR CO., INC.

2008 Honda Civic GX

2006-08 ENGINE Fan Controls (K20Z3) - Civic (All Except Si)

2008 Honda Civic GX

2006-08 ENGINE Fan Controls (K20Z3) - Civic (All Except Si)

SYMPTOM TROUBLESHOOTING INDEX

SYMPTOM TROUBLESHOOTING INDEX

Symptom

Diagnostic Procedure

Also check

for

Engine overheats

1. Check the coolant level.
2. Check for any engine coolant

leakage (from gaskets, hoses, O-
rings, etc.).

3. Check for dirt, leaves, or insects

on radiator and condenser.

4. Check for deteriorated coolant.
5. Check for a damaged or

deformed fan shroud.

6. Inspect the fan motors (see FAN

MOTOR TEST ) or fan relays
(see POWER RELAY TEST ).

7. Check the radiator cap (see

RADIATOR CAP TEST ).

8. Check the thermostat (see FAN

MOTOR TEST ).

9. Inspect the water pump (see

WATER PUMP
INSPECTION ).

10. Check for a plugged or

deteriorated radiator hoses.

11. Check for plugged heater core

or hoses.

12. Check for a damaged cylinder

head gasket.

The A/C condenser fan
runs at low speed, but it
does not run at high speed

A/C condenser fan high speed circuit
troubleshooting (see A/C

Cleanliness
and tightness

2008 Honda Civic GX

2006-08 ENGINE Fan Controls (K20Z3) - Civic (All Except Si)

when the engine coolant
temperature is above 199 °
F (93 °C)

CONDENSER FAN HIGH SPEED
CIRCUIT
TROUBLESHOOTING ).

of all
connectors

With the A/C off and the
engine coolant temperature
at 199 °F (93 °C) or below,
the radiator fan runs at
high speed and the A/C
condenser fan does not
run. When the engine
coolant temperature is
above 199 °F (93 °C), both
fans run at high speed

Remove the fan control relay, and
test.

If the relay is faulty, replace it.

If the relay is OK, check for a
short in the wire between the fan
control relay 5P socket terminal
No. 1 and radiator fan motor 2P
connector terminal No. 1.

Cleanliness
and tightness
of all
connectors

Both the radiator fan and
the A/C condenser fan run
at high speed with the
ignition switch ON (II), the
A/C off, and the engine
coolant temperature below
194 °F (90 °C)

Check for short in the wire between
A/C condenser fan relay 4P socket
terminal No. 3 and ECM connector
terminal A5.

Cleanliness
and tightness
of all
connectors

Both the radiator fan and
the A/C condenser fan run
at low speed with the
ignition switch ON (II) and
the A/C off

Check for short in the wire between
radiator fan relay 4P socket terminal
No. 4 and ECM connector terminal
A4.

Cleanliness
and tightness
of all
connectors

Both the radiator fan and
the A/C condenser fan do
not run at low speed with
the A/C on

Radiator and A/C condenser fans low
speed circuit troubleshooting (see
RADIATOR AND A/C
CONDENSER FAN LOW SPEED
CIRCUIT
TROUBLESHOOTING ).

Cleanliness
and tightness
of all
connectors

Both the radiator fan and
the A/C condenser fan run
at low speed, but the
radiator fan does not run at

RADIATOR FAN HIGH SPEED
CIRCUIT TROUBLESHOOTING

Cleanliness
and tightness

2008 Honda Civic GX

2006-08 ENGINE Fan Controls (K20Z3) - Civic (All Except Si)

CIRCUIT DIAGRAM

high speed when the
engine coolant temperature
is above 199 °F (93 °C)

(see ).

of all
connectors

Both the radiator fan and
the A/C condenser fan do
not run at high speed when
the engine coolant
temperature is above 199 T
(93 °C)

Check for open in the wire between
A/C condenser fan relay 4P socket
terminal No. 3 and ECM connector
terminal A5.

Cleanliness
and tightness
of all
connectors

2008 Honda Civic GX

2006-08 ENGINE Fan Controls (K20Z3) - Civic (All Except Si)