AK49BWL
GMT400 Forever!
In the trucks that applies to, the compressor relay was directly activated by the HVAC controller, and there was only one pressure switch on the low side for cycling. The high pressure switch indeed activated the recirc door. With the Vortec and later, the PCM assumes control over the compressor cycling, therefore there is no need for the high pressure switch to deal with the recirc.
Not only that, but on trucks that the high pressure switch actuated the recirc door, there was no button in the HVAC controller to actuate it yourself. I'd be hard pressed to find a 95+ controller that doesn't have the dedicated Recirc switch lol
Yeah that manual is referring to the 88-94 systems, note it talking about the blower fan relayS... There's only one in the newer models for the high blower speed.
Not only that, but on trucks that the high pressure switch actuated the recirc door, there was no button in the HVAC controller to actuate it yourself. I'd be hard pressed to find a 95+ controller that doesn't have the dedicated Recirc switch lol
Yeah that manual is referring to the 88-94 systems, note it talking about the blower fan relayS... There's only one in the newer models for the high blower speed.