ENGINE COOLING -
SPECIAL TOOLS
Tool
A
B
C
D
APS
TROUBLESHOOTING
INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptoms
Radiator fan does not operate.
Radiator fan does not change speed or stop.
INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
Inspection Procedure 1
Radiator fan does not operate.
Failure may occur on the power supply of the radiator fan controller and the
earth circuit.
Failure may also occur on the radiator fan controller and engine-ECU.
Special Tools/Troubleshooting
Number
Name
MB991223
Harness set
A: MB991219
A: Test harness
B: MB991220
B: LED harness
C: MB991221
C: LED harness
D: MB991222
adapter
D: Probe
MB991658
Test harness
MB991791
Throttle cotroller
Use
Measurement of terminal voltage
D
Inspection of radiator fan controller
D
A: Connector pin contact pressure
inspection
B: Power circuit inspection
C: Power circuit inspection
D: Commercial tester connection
Inspection of radiator fan controller
Inspection of radiator fan controller
[Use the accelerator pedal position sensor
disconnected from harness.]
Inspection procedure
Reference page
No.
1
14-3
2
14-5
Probable cause
D Malfunction of fusible link
D Malfunction of radiator fan relay
D Malfunction of radiator fan controller
D Malfunction of radiator fan motor
D Malfunction of engine-ECU
D Malfunction of harness, connector
14-3