Can a 2002 truck PCM and harness support hi and low speed electric fans?
#22
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Yes you can.
Pin 42 - empty - Fan 1 Control - This will be empty on 99-2002 harnesses. A pin can be added for electric fan control. Programming will enable the fan control. PCM supplies a GROUND to turn on a relay. If you have two fans, keep reading, pin for fan 2 will be on the RED connector C2. You must wire your fans through a relay.
Pin 33 - Dk Green - Fan 2 Control - some 99-02 harnesses will have a pin here, this was used for the HVAC Recirculation Door control. The PCM would control the A/C recirculation to help cool the a/c system if it got too hot. In an engine swap, programming can be changed to let this control a second cooling fan. Again, PCM supplies a GROUND to run on a relay. You must wire your fans through a relay.
Got this info from www.lt1swap.com.
Tim.
Pin 42 - empty - Fan 1 Control - This will be empty on 99-2002 harnesses. A pin can be added for electric fan control. Programming will enable the fan control. PCM supplies a GROUND to turn on a relay. If you have two fans, keep reading, pin for fan 2 will be on the RED connector C2. You must wire your fans through a relay.
Pin 33 - Dk Green - Fan 2 Control - some 99-02 harnesses will have a pin here, this was used for the HVAC Recirculation Door control. The PCM would control the A/C recirculation to help cool the a/c system if it got too hot. In an engine swap, programming can be changed to let this control a second cooling fan. Again, PCM supplies a GROUND to run on a relay. You must wire your fans through a relay.
Got this info from www.lt1swap.com.
Tim.
i have an 02 avalanche and my tunner guy says there is no setting in the hpt file to have both speeds set to work. any suggestions???