low speed fan not working?
- Thread starter charged87
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I had a similar problem with a custom tune and stock thermostat. Check for Diagnostic Trouble Codes first. If nothing, check to make sure your low speed fan circuit is working. Turning on the A/C on low (not MAX) should energize the low speed cooling fan after a minute or two. If that works as advertised, I would do a KAM reset.
Any progress? If the above doesn't fix it, re-install your custom tune with your desired fan settings. My problem was software related, not hardware, so between a KAM reset and re-loading my tune in the PCM, my issue was resolved. I now monitor ECT with my AeroForce Interceptor and the low and high speed fan work perfectly.
Clears Keep Alive Memory. Some handheld programmers have a KAM reset function. If yours does not, just disconnect the negative lead on your battery and turn your headlight switch ON to discharge any remaining voltage. I usually let the car sit in that condition for one hour, then turn the headlight switch OFF and reconnect your battery, KAM reset complete.
Ok great... it won't effect with the tune? I'll try that and reload my custom tune then make the fan settings again.
No, won't effect the tune one bit.
No luck... did the KAM reset fan only comes on at 188 in high. The low speed at 182 doesn't come on. I even swapped the high and low relays and same thing happened only high speed 188 comes on. I'm stumped? I mean maybe it's no big deal the car keeps cool but I would like to know why it doesn't work.
Are you using an SCT X4? Try programming 186 low and 192 high. It should not matter, but give it a shot.
Yes X4 I'll give it a shot but can't see it making a difference
Do you know for a FACT that the low speed fan was working before you altered the tune?
Did you scan for fault codes with your X4 and there were none present?
If the new fan settings don't work, you need to troubleshoot your low speed fan circuit. Since you already swapped the relays and ruled them out, you could have a wiring problem (short or open) or the fan motor might be bad for low speed. Attached is a schematic for a 2008, just so you can see how the electrical system works. The relay terminals/locations in the fuse box may be different, but the fan wiring is the same.
Did you scan for fault codes with your X4 and there were none present?
If the new fan settings don't work, you need to troubleshoot your low speed fan circuit. Since you already swapped the relays and ruled them out, you could have a wiring problem (short or open) or the fan motor might be bad for low speed. Attached is a schematic for a 2008, just so you can see how the electrical system works. The relay terminals/locations in the fuse box may be different, but the fan wiring is the same.
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Was told by a few that the fan resistor is the problem on these. . It's mounted right on the shroud and almost the price of a complete fan assembly. . I just ordered the 13-14 gt500 fan assembly so I hope this solves the problem
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