There are two diodes in the fan ciruit. One prevents the otterstat from switching on the AC compressor, and the other one prevents the AC compressor from powering the IGN circuit via the otterstat. They are taped together underneith and on the right side of the main harness in the electrical compartment. It is possible yours have either failed, inproperly installed after PO work, or nonexistant. However there is another possibility. If the PO installed some "custom" wiring when installing the new compressor, and tied it directly into the otterstat circuit since the two devices are relatively close together in the engine compartment. Visually check that first by verifying that there is only ONE cable going into the AC compressor (pink on harness side) and that nothing is tapped into it. Also check the otterstat wires to ensure there are only two of them and nothing is tapped into them. Once that checks out verify the presence, installation, and operation of the diodes. Jim Reeve DMC6960 --- In dmcnews@xxxxxxxxxxxxxxx, "Marv Hein" <marvhein@xxxx> wrote: > > My PO installed a new A/C compressor and it seems some monkey > business may have happened in the process. I didn't notice it until > recently because I ran the A/C all summer. > > Whenever I turned on my A/C, my fans would come on and stay on as > long as the control was set to any of the A/C settings. I > understand this is good. However, the inverse seems not so good. > > Example: > Vent controls set to "vent," engine idling, compressor not running > and front fans not running. Engine warms up to around the 1/4 mark, > front fans come on and compressor simultaneously engages. Cool air > comes out of my vents. I can overcome it by turning the temp > control to HOT, but the compressor is still doing its thing. I > have "automatic A/C!" > > I'm guessing this is abnormal behavior? Trickery, if there was > trickery, may lie in the relays? > > Any suggestions appreciated. > > Thanks, > Marv > #10820 > To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/