2008 coolant fan issue
#1
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I have a 2008 6.2 in my shop that was wired by a previous mechanic. I have been asked to complete job as previous mechanic left. My issue is the coolant fans do not come on when commanded on. I have checked the wiring all the way back to pcm terminal 17 and 58 if i ground at pcm connector fans come on as i understand they should. When engine is running and up to temp scan data shows fan commanded on but does not ground either terminal 17 or 58. If i go to scan tool special function and command fan on still no ground signal any ideas? I have tried 2 pcms same result
#2
TECH Fanatic
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This is a very similar situation I encountered with my 896 PCM controlling E-fans. Apparently, I did not get enough of the donor vehicle system to make this work with an 896 PCM but could have worked with a 411 PCM. However, I never tried a 411 and eventually got tired of doing all that you describe above to still wind up with no fans.
I went with an external fan controller - actually, two for my two El Camino fans. Four Seasons part number 35879 for about 35 bucks each. This leaves me with both fans thermostatically controlled with adjustable "on" temperatures and a wire on one controller used to instantly turn on the passenger side fan when I turn the air conditioning on.
My two fans are completely independent of each other with their own power, grounds, adjustable thermostat, relays, and temperature probe for complete independence and best reliability.
Rick
I went with an external fan controller - actually, two for my two El Camino fans. Four Seasons part number 35879 for about 35 bucks each. This leaves me with both fans thermostatically controlled with adjustable "on" temperatures and a wire on one controller used to instantly turn on the passenger side fan when I turn the air conditioning on.
My two fans are completely independent of each other with their own power, grounds, adjustable thermostat, relays, and temperature probe for complete independence and best reliability.
Rick
#3
TECH Fanatic
iTrader: (1)
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I have a 2008 6.2 in my shop that was wired by a previous mechanic. I have been asked to complete job as previous mechanic left. My issue is the coolant fans do not come on when commanded on. I have checked the wiring all the way back to pcm terminal 17 and 58 if i ground at pcm connector fans come on as i understand they should. When engine is running and up to temp scan data shows fan commanded on but does not ground either terminal 17 or 58. If i go to scan tool special function and command fan on still no ground signal any ideas? I have tried 2 pcms same result