2002 Thunderbird Hydraulic Cooling Fan Conversion

actuator is on the back of the hydro pump it is a solenoid valve . low engine temp =low frequency pluswith to actuator =valve in actuator open bypassing pressure to hydro fan motor. high engine temp =high frequency pluswith to actuator closes bypass . when ac is on and high pressure switch closes = high frequency pluswith to actuator =high fan speed at once .this is ok on the hydro system . not on the ele fan system .there will be voltage spike .reason for micro processor in 2003 fan to slow start fan when ac is on .2003 fan will slow start on temperature go through duty cycle shut off ,slow start go through duty cycle shut off . as long as ac high pressure has pressure switch closed fan will run on high when inside car is cool enough to drop high pressure below pressure limit fan will shut off if engine temp is in range . all that being said .how many high mileage 2003 thunderbirds or lincoln ls 2003 have fan problems that would be the big answer.
 

medurham

Well-Known Member
the controller is in the ecm on 2002 did they replace the ecm ?
No, the flex a lite 183 comes with its own controller. It’s adjustable during initial setup. The system is complete and self contained so does not rely on the ecm command signal. It has its own temp sensor and power wire with fuse block.
 
can the new 2013 electric fan be connected to those wires for control?
It's very unlikely that circuit has the power needed to run an electric fan directly. Although it could be used to trip a relay from a stronger power source, preferably a dedicated source. Fans typically draw 15 or more Amps depending on the size. Starting of the fan often requires more. I would recommend the variable speed or slow start types.
 
It's very unlikely that circuit has the power needed to run an electric fan directly. Although it could be used to trip a relay from a stronger power source, preferably a dedicated source. Fans typically draw 15 or more Amps depending on the size. Starting of the fan often requires more. I would recommend the variable speed or slow start types.
I bought a 2003 thunderbird fan, it has two control wires I was planning to connect to actuator wires, I wonder if I can dissasemble fan to get to the red and black wires that must be internally connected to some kind of internal relay. I do have the black and red wires connected to ground and power from fuse box 8 gauge wires. im waiting on 2002 wiring diagram to compare.
 

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  • fan sechem tbird.pdf
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It's very unlikely that circuit has the power needed to run an electric fan directly. Although it could be used to trip a relay from a stronger power source, preferably a dedicated source. Fans typically draw 15 or more Amps depending on the size. Starting of the fan often requires more. I would recommend the variable speed or slow start types.
so by looking at this schematic, assuming the circuit is similar to a 2002 thunderbird, in theory the PCM sends a pulse to complete a ground to activate relay inside fan, making fan work or we can put a thermostat or a temp probe to 18BN wire or brown wire from the new fan it would be NCA BLK yellow on 2003 wiring diagram posted earlier. I will try this tomorrow.
 

Attachments

  • 2009-11-29_005557_00_LS_Cooling_system_wiring_diagram.jpg
    2009-11-29_005557_00_LS_Cooling_system_wiring_diagram.jpg
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so by looking at this schematic, assuming the circuit is similar to a 2002 thunderbird, in theory the PCM sends a pulse to complete a ground to activate relay inside fan, making fan work or we can put a thermostat or a temp probe to 18BN wire or brown wire from the new fan it would be NCA BLK yellow on 2003 wiring diagram posted earlier. I will try this tomorrow.
You might want to also check the PCM output voltage to be certain they are similar between the '02 and '03. Computer outputs that do signaling can have often lower voltage. 5 VDC typically. And also that it is switching on and off properly, and not opposite of your needs. .Only use a computer safe voltage tester if probing wires. A service manual may give the proper output volts and timing for the circuit.
 
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You might want to also check the PCM output voltage to be certain they are similar between the '02 and '03. Computer outputs that do signaling can have often lower voltage. 5 VDC typically. And also that it is switching on and off properly, and not opposite of your needs. .Only use a computer safe voltage tester if probing wires. A service manual may give the proper output volts and timing for the circuit.
I connected brown wire to NCA3 that is your pulse (ground) and green and yellow to NCA4 that is your plus 12vdc from the actuator. with new fan that has a microprocessor, as long as I had the NCA4 connected to green and yellow from actuator wiring, I got 12vdc, the fan kicked on. The voltage will not show up in NCA4 until you reach temperature. the other two ties NCA2 is ground and NCA1 positive 60amps . I don't think you need any relays so far is just a straight connection to the actuator wires fro control of Cooling fan. will drive it later on .
 

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  • fan sechem tbird.pdf
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Need to remove everything pertaining to the hydraulic cooling fan, pump, reservoir, lines, expansion tank. Install a 100’’ sepentin fan belt, install a flex a lite 3400 cam 15´’ fan and shroud assembly, install a flex a lite fan speed control #31165 , and fine tune adjustments... I check my engine block temperature with OBDII reader, stays 208 degrees with a/c on, a hot day.
How do you route the 100” belt after the hydraulic pump is removed?
 
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