MAF Conversion EEC Pin 43 Conflict...HELP!!!

**jrosengarth** · 08-03-2007, 05:53 PM

I have a 93 F-150 that I have replaced the computer with an A9P for a MAF conversion, and while repinning the PCM harness I found pin 43 occupied (L HEGO on the A9P). My wiring diagrams for the old computer say this pin is spliced to the wire going from the A/C pressure switch to the A/C blower switch. Sounds to me like it's just a way for the computer to tell if the A/C compressor is running when switched on, right? My question is: what do I do with this wire? Can I just pull it and leave it hanging, or does this belong in another pin position on the new computer? I do not have the EVTM for the A9P (92 Mustang GT). Any help would be most appreciated!
-J

**Joel50** · 08-05-2007, 06:57 AM

Yep....that's the A/C Demand signal in a 4.9L ECM....you could remove it and leave it disconnected, it's not used in the A9P as you see here .

**jrosengarth** · 08-06-2007, 11:30 AM

That's what I'll do then. Thanks!
-J



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