Diagnosis and Testing (4.0L & 4.7L)

The PCM will enter a DTC in memory if it detects a problem in the auxiliary cooling fan relay or circuit. If the electric cooling fan is inoperative, check the 15A fuse in the junction block and the 40 A fuse in the Power Distribution Center (PDC) with a 12 volt test lamp or DVOM. Refer to the inside of the PDC cover for the exact location of the fuse. If fuses are okay, refer to ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS in ELECTRICAL for cooling fan and relay circuit schematic.