Power flows from Fuse #23 to the low and high fan relates. The control coils in the relays are grounded by the front control module. If the relays don't get ground, they won't switch the relay contacts and won't start the fans.
Start by applying battery power and ground to the radiator fan to see if it works when supplied power directly.
Yank the fan relays. Using a digital meter, check for battery voltage on terminal 86 in the low speed relay socket. You should see battery voltage. With the AC on and engine running, check for ground on terminal 85. If you're not getting ground the next question is: is the front control module not getting the command or is the front control module bad? Perform the same tests on the high speed rely. Battery power on terminal 85 and control coil grond on terminal 86
Did you check the fuse and the voltage at the supply side of the relays? How about the wiring and particularly the connectors? Also, it is not unusual for a new temperature sensor to be faulty - try jumping the contacts in the sensor connector to see if the fans activate.
I am assuming that you also checked the fuses for it to so now we have to check the wires and connectors check the wires for continuity and voltage from the pcm and from fuses in the power distribution box and relays also make sure that they fit tight in the connector inside the box so now if all fuses & relays are tight and the connectors are good and not broken and you have continuity through all the wires and no breaks are found under the power distribution box and from the temp sensor then the pcm fan controller chip has shorted out also did this start after giving someone a jump start or did you ground out the battery cables by mistake if so you might have blown a fuse link these are small gaged wires in the line that blow out to avoid over voltage from flowing through the system and damaging the pcm and components
Answers & Comments
Power flows from Fuse #23 to the low and high fan relates. The control coils in the relays are grounded by the front control module. If the relays don't get ground, they won't switch the relay contacts and won't start the fans.
Start by applying battery power and ground to the radiator fan to see if it works when supplied power directly.
Yank the fan relays. Using a digital meter, check for battery voltage on terminal 86 in the low speed relay socket. You should see battery voltage. With the AC on and engine running, check for ground on terminal 85. If you're not getting ground the next question is: is the front control module not getting the command or is the front control module bad? Perform the same tests on the high speed rely. Battery power on terminal 85 and control coil grond on terminal 86
Did you check the fuse and the voltage at the supply side of the relays? How about the wiring and particularly the connectors? Also, it is not unusual for a new temperature sensor to be faulty - try jumping the contacts in the sensor connector to see if the fans activate.
I am assuming that you also checked the fuses for it to so now we have to check the wires and connectors check the wires for continuity and voltage from the pcm and from fuses in the power distribution box and relays also make sure that they fit tight in the connector inside the box so now if all fuses & relays are tight and the connectors are good and not broken and you have continuity through all the wires and no breaks are found under the power distribution box and from the temp sensor then the pcm fan controller chip has shorted out also did this start after giving someone a jump start or did you ground out the battery cables by mistake if so you might have blown a fuse link these are small gaged wires in the line that blow out to avoid over voltage from flowing through the system and damaging the pcm and components