Radiator Cooling Fan Motor: Testing and Inspection

1. Run engine to normal operating temperature.

2. Check wiring connector in C25, C9 and C26 for proper engagement.

3. Connect diagnostic read out tool DRB II to diagnostic connector. Check for fault codes.

4. If fault code 88,12,35,55 is detected, proceed with next step.

5. With ignition switch in Run position, test for battery voltage at fan relay single pin connector. If battery voltage is detected or if voltage reads at zero to one volt, proceed with next step.

6. With ignition switch in Off position, disconnect the 60-way connector from engine controller and return ignition switch to Run position, then proceed as follows:

Engine Controller 60-way Connector.:

a. Test for battery voltage at terminal 31 of 60-way connector.
7. If battery voltage exists and female terminal is not damaged, replace engine controller. If no battery voltage exists, repair open or short in circuit C27.
8. With ignition switch in Off position, disconnect 60-way connector from engine controller and return ignition switch to Run position. Test for battery voltage at single pin connector on fan relay. If battery voltage exists, replace engine controller. If voltage is zero to one volt proceed to last step.
9. With ignition switch in Run position, test for battery voltage at wire C27 in 3-way connector of fan relay. If battery voltage exists, replace fan relay. If voltage is zero to one, repair open or short in circuit C27.
10. Turn ignition switch Off, connect 60-way connector and test system.