Highlander 2WD V6-3.3L (3MZ-FE) Hybrid (2006)
Radiator Cooling Fan Control Module: Testing and Inspection
COOLING FAN ECU
ON-VEHICLE INSPECTION
Cooling Fan ECU Harness Side Connector (NO.1 And NO.2)
1. CHECK COOLING FAN ECU (NO.1 and NO.2)
a) Inspect the input voltage.
1) Disconnect the cooling fan ECU connectors.
2) Turn the ignition switch on.
3) Measure the voltage between terminals +13 and GND.
Standard voltage: 8 to 15 Volts
If the voltage is not as specified, check the fusible links, fuses, wire harness and fan relay.
4) Reconnect the connectors.
HINT: Wire harness condition is diagnosed by cooling fan operation.
b) Check the HV control ECU power source.
c) Check RFC1 and RFC2 signal generation.
NOTICE: Perform this inspection when coolant temperature is 82°C (180°F)
1) Connect an oscilloscope to terminals RFC1 (RFC2) and E1 of the HV control ECU.