Gentlemen, what am I looking at here?
The A/C (I got EATC) takes its sweet time to kick in. I think I'd need to check the refrigerant pressure, but it seems to be OK, because when it does kick in, the air blows hella cold.
The symptoms to clear things up:
1. EATC works, save for the dead backlighting. It can randomly switch between Celsius and Fahrenheit.
2. The vent diverter flaps work, reach every direction as commanded (floor, vents, windshield, closed cycle).
3. When turned on, the A/C will not blow for a long time. Note this: IT DOES NOT blow hot air from the heater core, it blows fresh air when running in any mode other than Max A/C (in the latter case, it will recycle the cabin air).
4. After a longer time, it starts blowing freezing cold air - as it should when the interior is hot.
I tested it today in these conditions:
Outdoor temp 64 F, cabin temp 72 F (the car sat in the sun). Wouldn't blow cold air from the A/C, just the cooler air from the outside (and recycle air in Max A/C). After 3-4 minutes of driving and fiddling with the EATC controls (blower speed, vent selection, Max A/C, turning it off and on again) I left in Max A/C, only then did it start blowing cold A/C air (after 1 more minute or so). When it blows cold air, it's hella cold, so I think the A/C charge is OK. The temp sensors read from the PCM read OK.
Day two of testing:
Outside temp 76 F, cabin at just about the same, fired her up first time this day.
The A/C compressor took 10 minutes (!) to kick in; then it was blowing hella cold air, so I guess there's no coolant leak.
Left the car for 10 mins on a parking lot, went back, fired it up, the same happened. This time it took the A/C compressor 2-3 minutes to kick in.
Each time it happened I was switching between Max A/C, Normal A/C, and Auto, to no effect, until the compressor "felt like it".
Ran the EATC self diagnostic routine, no codes.
Day three:
Took a feeler gauge to the clutch plate on the A/C compressor. Read ~0.3-3.5 mm at every 120 deg. point around the circle, and the service manual says the gap setting should be within 0.35-0.75 mm, so I guess it's OK.
I'm now leaning to an electrical control issue. It's like something is not commanding to energize the A/C compressor clutch magnet to run, as if there was a feedback missing from one of the sensors in the A/C system or the EATC isn't running the compressor until it does.
Given that my EATC has developed a 'homesick syndrome' (switching from Celsius to Fahrenheit by itself), should I suspect that there's a PCB solder going bad in it and POSSIBLY causing this compressor run delay? As in, the EATC needs to stay tickled with power until it starts responding to what the A/C system sensors tell it and turn on the compressor?
And if not, what sensor outputs EXACTLY make the EATC resolve that the A/C compressor should run or not? I'll repeat - the A/C kicks in when the compressor is 'told' to kick in, and it is told with a HUGE delay - like, 10 minutes of driving at 80 F outside and 80-85 F in the cabin, when I start the car that sat for hours in the sun (and in this case the EATC blows air into the cabin, just without the A/C until the compressor kicks in).
The A/C (I got EATC) takes its sweet time to kick in. I think I'd need to check the refrigerant pressure, but it seems to be OK, because when it does kick in, the air blows hella cold.
The symptoms to clear things up:
1. EATC works, save for the dead backlighting. It can randomly switch between Celsius and Fahrenheit.
2. The vent diverter flaps work, reach every direction as commanded (floor, vents, windshield, closed cycle).
3. When turned on, the A/C will not blow for a long time. Note this: IT DOES NOT blow hot air from the heater core, it blows fresh air when running in any mode other than Max A/C (in the latter case, it will recycle the cabin air).
4. After a longer time, it starts blowing freezing cold air - as it should when the interior is hot.
I tested it today in these conditions:
Outdoor temp 64 F, cabin temp 72 F (the car sat in the sun). Wouldn't blow cold air from the A/C, just the cooler air from the outside (and recycle air in Max A/C). After 3-4 minutes of driving and fiddling with the EATC controls (blower speed, vent selection, Max A/C, turning it off and on again) I left in Max A/C, only then did it start blowing cold A/C air (after 1 more minute or so). When it blows cold air, it's hella cold, so I think the A/C charge is OK. The temp sensors read from the PCM read OK.
Day two of testing:
Outside temp 76 F, cabin at just about the same, fired her up first time this day.
The A/C compressor took 10 minutes (!) to kick in; then it was blowing hella cold air, so I guess there's no coolant leak.
Left the car for 10 mins on a parking lot, went back, fired it up, the same happened. This time it took the A/C compressor 2-3 minutes to kick in.
Each time it happened I was switching between Max A/C, Normal A/C, and Auto, to no effect, until the compressor "felt like it".
Ran the EATC self diagnostic routine, no codes.
Day three:
Took a feeler gauge to the clutch plate on the A/C compressor. Read ~0.3-3.5 mm at every 120 deg. point around the circle, and the service manual says the gap setting should be within 0.35-0.75 mm, so I guess it's OK.
I'm now leaning to an electrical control issue. It's like something is not commanding to energize the A/C compressor clutch magnet to run, as if there was a feedback missing from one of the sensors in the A/C system or the EATC isn't running the compressor until it does.
Given that my EATC has developed a 'homesick syndrome' (switching from Celsius to Fahrenheit by itself), should I suspect that there's a PCB solder going bad in it and POSSIBLY causing this compressor run delay? As in, the EATC needs to stay tickled with power until it starts responding to what the A/C system sensors tell it and turn on the compressor?
And if not, what sensor outputs EXACTLY make the EATC resolve that the A/C compressor should run or not? I'll repeat - the A/C kicks in when the compressor is 'told' to kick in, and it is told with a HUGE delay - like, 10 minutes of driving at 80 F outside and 80-85 F in the cabin, when I start the car that sat for hours in the sun (and in this case the EATC blows air into the cabin, just without the A/C until the compressor kicks in).
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