4: Radiator Fan and Condenser Fan Do Not Change Speed or Stop

Inspection Procedure 4: Radiator fan and condenser fan do not change speed or stop
Radiator Fan and Condenser Fan Drive Circuit.

CIRCUIT OPERATION
^ The fan control module is powered from fusible link number 5.
^ The ECM or PCM 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 or PCM activates the fan control module to drive the radiator fan motor and condenser fan motor.

TECHNICAL DESCRIPTION
The fan control module has variable control of the radiator fan motor and the condenser fan motor speeds using signals transmitted from the ECM or PCM .

TROUBLESHOOTING HINTS
^ Malfunction of fan control relay
^ Malfunction of fan control module
^ Malfunction of ECM or PCM
^ Malfunction of ECM or PCM

DIAGNOSIS
Required Special Tool: MB991223: Harness Set

STEP 1. Check the fan control relay.
Refer to Fan Control Relay Continuity Check.
Q: Is the fan control relay in good condition?
YES: Go to Step 2.
NO: Replace the part, then go to Step 6.

STEP 2. Check the harness wire between fan control relay connector A-1 3X and fan control module connector A-30.
Q: Are the harness wire between fan control relay connector A-1 3X and fan control module connector A30 damaged?
YES: Repair or replace the part, then go to Step 6.
NO: Go to Step 3.

STEP 3. Check the circuit at ECM connector C-109 <2.4L M/T>, C-111 <3.0L-M/T>or PCM connector C-110 <2.4L-A/T>, C-112 <3.0L-A/T>.
1. Connect ECM connector C-109 <2.4L-M/T>, C-111 <3.0L-M/T> or PCM connector C-110 <2.4L-A/T>, C-112 <3.0L-A/T>.
2. Start the engine and run it at idle. [Engine coolant temperature: 80°C (176°F) A�]
3. Measure the voltage between terminal number 21 <2.4L-M/ T> or 18 <2.4L-A/T, 3.0L> and ground.
Q: Is the voltage 0 - 0.3 volt when radiator fan is not operating?
YES: Go to Step 6.
NO: Go to Step 4.

STEP 4. Check the harness wire between ECM connector C-109 <2.4L-M/T>, C-111 <3.0L-M/T>or PCM connector C110 <2.4L-A/T>, C-112 <3.0L-A/T> and fan control module connector A-30.

NOTE: If intermediate connector C-06 is damaged, repair or replace it.

Q: Are the harness wires between ECM connector C-109 <2.4L-M/T>, C-111 <3.0L-M/T>or PCM connector C-110 <2.4L-A/T>, C-112 <3.0L-A/T> and fan control module connector A-30 damaged?
YES: Repair or replace them, then go to Step 6.
NO: Go to Step 5.

STEP 5. Check the fan control module at ECM connector C-109 <2.4L-M/T>, C-111 <3.0L-M/T>or PCM connector C110 <2.4L-A/T>, C-112 <3.0L-A/T>.
1. Connect ECM connector C-109 <2.4L-M/T>, C-111 <3.0L M/T> or PCM connector C-110 <2.4L-A/T>, C-112 <3.0L-A/T>.
2. Turn the ignition switch to " ON" position.
3. Pull out the terminal number 21 <2.4L-M/T> or 18 <2.4L-A/ T. 3.0L> and connect it to the body ground.
Q: Do the radiator fan motor and condenser fan motor stop?
YES: Replace the ECM or PCM . Then go to Step 6.
NO: Replace the radiator fan motor and fan control module assembly. Then go to Step 6.

STEP 6. Check the symptoms. Q: Do the radiator fan and condenser fan operate correctly?
YES: This diagnosis is complete.
NO: Return to Step 1.