2004 honda Odyssey front air cond sometimes works
strange, why strange, the car has protection built it to save you from blowing up the freon loop parts, one such part is the Hi/lo pressure switch.
the way to fix all systems is to diagnose it
and the best time is when it fails (or its gobsmack time)
1: check 1. is the compressor off? clutch energized?
yes, then maybe the brain told it to do so, in fact i bet it did.
if clutch is energized and the compressor is running full speed.
belt not slipping (i use a hand opto tachmeter.)
2: clutch dead, and 12v on coil reads 0v. (commanded to do so)
3: I then check the Hi/lo switch, 12v on both sides.
if not , the loop is too much freon , or too little. most times its too low. takes vast pressures to trip the high (its all in the FSM read it)
4: the HI/low is not tripped.
5: the ECU on most newer cars does all the A/C protrection logic,
unlike olden days with discrete a.c logic box.
The ECU on most newer cars can cut the cluch for:
1: evap core, freeze up (icing,) (normal in some cases but if excessive is a bad expansion valve "stuck".)
2: engine overheat or the ECT is fibbing its buns off.
3: engine overload. (driving too fast, too much load, or up hills , passing or all three,. slow down)
4: the ECU may drop A/C on some cars if the ECU goes to limphome mode, (saving engine from overheating, preemptively.
so is the check engine lamp on running. ah, bingo?
read the HVAC page online
at alldata.com, its there all the time.... read it.
my post is generic today, for 2004 era cars... RTM
on Nov 11, 2013