Fix code P1489 and overheating 300M
Owners who have an P1489 and overheating 300M with trouble code High Speed Fan CTRL Relay Circuit, here’s what to do. Remove the high speed fan relay and use a digital multimeter to check for power on the two terminals of the electrical connector. If you show power, reinstall the relay. Then ground the dark blue/light green wire at pin 69 of the PCM. The relay should click. If it doesn’t try swapping in a new relay or run a continuity test on the wiring harness.
© 2012 Rick Muscoplat
Posted on by Rick Muscoplat