chason

Hey gang,

I have two issues--heating and cooling. I've tried a lot of things, tested what I know how to, and am at my wits end. I can rebuild an engine, but can't seem to get this down. New tires and surprise bills have funds tight right now, thus adding to the frustration. I'm two steps away from draining my savings and taking it to the shop. Please halp!

Down to business:

Heating -- The heater in my car has not worked since the day I bought it. After a couple of recommendations here, I thought I could replace the heater control valve for $40 and call it a day. Wrong. I should have tested the old one first by moving the vacuum cable, because the old one works. When you move the vacuum cables around to apply vacuum to the HCV, it moves fine. The electrical connector there is reading 12 volts, so the climate control is telling it to turn on, but it doesn't move. Now, replacing the electronic vacuum switch would make the HCV open, but opening the HCV manually still doesn't produce heat. What do?

Cooling -- The A/C in this car has always worked wonderfully, until a few months ago. The last time I looked at this, I hooked up gauges, looked at pressures, bypassed the low pressure switch, tested the relay, but still can't get the compressor to turn on. When I bypass the relay, the compressor kicks on and the A/C gets ice cold.

Other info -- I ran the diagnostics check on the climate control unit, I'm pulling codes 21, 42, and 43.

21 = solar sensor, it's been dark and rainy here, so maybe that's the reason... I'll check again as soon as there's some sun around--hopefully tomorrow.

42 = air inlet servomotor circuit

43 = air outlet servomotor circuit

Would any of this cause the compressor or heat to not kick on? It seems like all of those wouldn't halt the operation of heat or cool. Is this necessary to fix before moving on?

Where do I go from here?

Thanks

t2d2

iTrader: (8)

Mine stores the #21 CEL unless it's in direct sunlight, even if it's plenty bright out. I was a bit concerned about that at first when diagnosing heater stuff. I haven't dealt with codes #42/43, but that sounds like a reasonable place to start. If opening the HCV manually produces no heat, it seems like it has to be something along the lines of the blend door or whatever inner workings route hot and cold air as needed. Inlet/outlet servomotor circuits sound like as good a culprit as any.

chason

Tested in sunlight, code 21 is no longer.

I'm still skeptical that fixing 42 and 43 are going to fix my issues... like I said, when you manually kick the compressor on the A/C runs great, but I suppose they need to be done anyway.