2001 Chevy Tahoe Z71 4x4 , installed a 3 relay harness for duel fans . Ok I did everything that was on this schematic and the fans won't turn on run

[Panchosancho]

2001 4x4 Tahoe Z71 fan upgrade . Fans won't turn on while it's runing . Turn off and they turn on wtf

 

[afpj]

I believe you need a tune to tell pcm to activate control signal. I didn't understand the turn off then turn on comment. I've seen multiple threads on this... recommend a search for threads on efan conversion... others with personal experience should chime in, but it's a holiday weekend...

 

[Tonyrodz]

I believe you need a tune to tell pcm to activate control signal. I didn't understand the turn off then turn on comment. I've seen multiple threads on this... recommend a search for threads on efan conversion... others with personal experience should chime in, but it's a holiday weekend...

Def need a tune to tell the pcm to turn the fans on.

 

[Fless]

I guess we don't know what schematic was used.