Mitsubishi Eclipse / Eclipse Spyder (2000-2002). Service and repair manual — part 344

ENGINE COOLING DIAGNOSIS

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COOLING SYSTEM

14-7

AC005065

<3.0L ENGINE>

AB

AC000242

FUSIBLE LINK (5) AND
CONNECTORS: A-13X, A-21X

FUSIBLE
LINK (5)

BATTERY

A-21X

A-13X

AB

AC000260AB

CONDENSER FAN
MOTOR CONNECTOR
AND CONNECTOR: A-30

CONDENSER
FAN MOTOR
CONNECTOR

A-30

RADIATOR
FAN

ENGINE COOLING DIAGNOSIS

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COOLING SYSTEM

14-8

CIRCUIT OPERATION

•

The fan controller is powered from fusible link
number 5.

•

The ECM <M/T> or PCM <A/T> judges the
required revolution speed of radiator fan motor
and condenser fan motor using the input signals
transmitted from A/C switch, automatic
compressor controller, vehicle speed sensor and
engine coolant temperature sensor. The ECM
<M/T> or PCM <A/T> activates the fan controller
to drive the radiator fan motor and condenser fan
motor.

TECHNICAL DESCRIPTION

•

The cause could be a malfunction of the fan
controller power supply or ground circuit.

•

The cause could also be a malfunction of the fan
controller or the ECM <M/T> or PCM <A/T>.

TROUBLESHOOTING HINTS

•

Malfunction of fusible link

•

Malfunction of fan control relay

•

Malfunction of fan controller

•

Malfunction of ECM <M/T> or PCM <A/T>

•

Damaged wiring harness or connector

DIAGNOSIS

Required Special Tool:
MB991223: Harness Set

STEP 1. Check the circuit at fan controller connector A-30.
(1) Disconnect fan controller connector A-30, and measure at

the harness side connector.

(2) Measure the voltage between terminal number 3 and

ground.

•

When the ignition switch is turned to "ON" position,
voltage should be battery positive voltage.

Q: Is the voltage battery positive voltage when the ignition

switch is turned to "ON" position?
YES : Go to Step 7.
NO : Go to Step 2.

STEP 2. Check the fan control relay.
Refer to

P.14-18

.

Q: Is the fan control relay in good condition?

YES : Go to Step 3.
NO : Replace it, then go to Step 10.

AC000244

CONNECTOR: C-07

AC

AC000245 AE

CONNECTOR:
C-49 <2.4L-M/T>, C-50 <2.4L-A/T>
C-51 <3.0L-M/T>, C-52 <3.0L-A/T>

ECM <M/T>
OR
PCM <A/T>

AC000246

CONNECTOR A-30

AB

ENGINE COOLING DIAGNOSIS

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COOLING SYSTEM

14-9

STEP 3. Check for continuity between fusible link number
5 and fan control relay connector A-13X.
Q: Are the harness wires between fusible link number 5

and fan control relay connector A-13X damaged?
YES : Repair or replace them, then go to Step 12.
NO : Go to Step 4.

STEP 4. Check for continuity between fan control relay
connector A-13X and fan controller connector A-30.
Q: Are the harness wires between fan control relay

connector A-13X and fan controller connector A-30
damaged?
YES : Repair or replace them, then go to Step 12.
NO : Go to Step 5.

STEP 5. Check for continuity between MFI relay connector
A-21X and fan control relay connector A-13X.
Q: Are the harness wires between MFI relay connector A-

21X and fan control relay connector A-13X damaged?
YES : Repair or replace them, then go to Step 12.
NO : Go to Step 6.

AC000247AB

BATTERY

FUSIBLE LINK (5) AND
CONNECTOR: A-13X

A-13X

FUSIBLE
LINK (5)

AC000248AB

CONNECTOR: A-13X

BATTERY

AC000270 AB

CONNECTOR: A-30

RADIATOR
FAN

AC000250

BATTERY

CONNECTORS: A-13X, A-21X

A-13X

A-21X

AB

ENGINE COOLING DIAGNOSIS

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COOLING SYSTEM

14-10

STEP 6. Check for continuity between fan control relay
connector A-13X and ground.
Q: Are the harness wires between fan control relay

connector A-13X and ground damaged?
YES : Repair or replace them, then go to Step 12.
NO : There is no action to be taken.

STEP 7. Check the circuit at fan controller connector A-30.
(1) Disconnect fan controller connector A-30, and measure at

the harness side connector.

(2) Measure the resistance between terminal number 1 and

ground.

Q: Is the resistance less than 2 ohm?

YES : Go to Step 9.
NO : Go to Step 8.

STEP 8. Check the harness wire between fan controller
connector A-30 and ground.
Q: Are the harness wires between fan controller connector

A-30 and ground damaged?
YES : Repair or replace them, then go to Step 12.
NO : There is no action to be taken.

AC000248AB

CONNECTOR: A-13X

BATTERY

AC000252 AB

CONNECTOR: A-30

AC000270 AB

CONNECTOR: A-30

RADIATOR
FAN