2008 honda accord air will not work ,has freon ,relay works but compressor will not kick on.
#1 top A/C post here ever. bravo that.
this is caused by by the AC brain.
(location varies by year, and country)
A/C brain discrete, cira 90s
to after 2007 , they moved the brain, now pure software inside
the ECU or BCM , on most cars.
it really dont matter much where it is until you get to back probe the bugger. right?
so , here is the reasons for A/C clutch dead.
1:clutch bad, apply 12v to it see if it works (wires discon, please)
do so for on 1second, so as not damage system.
check for coil ohms near 1ohm. at clutch.
infinity is bad coil.
OR do :
1b" 12v to coil AC on? any volt meter works. 11 to 15v typical.
13.3 to 14.7 running engine typical.
yes, clutch dead.
2: 12v not at coil of clutch bad relay.
3: relay coil not energized.
3a: power to relay not on coil, if yes, bad relay .
3b: relay coil dead. no power. the brain has it shut down!
4: the brain, stops the AC for all these reasons
simple answer , inputs wrong.
a: too low freon pressure, in truth or sensor fibbing
b: too high freon pressure, same, reasons.
c: ENGINE over load, (pulling trailer or going WOT )
d: engine overheat. (ecu say so or AC has its own sensor saying so, RTM.
e: Evap core (the cold core in dash) has frozen over to a ice brick. (a freeze sensor is there) caused by stuck open expansion valve. in core.
f: no power to AC brain, 90s cars. or missing ground,
g: AC not on, or brain can not see fan going, usual the is just
the 12vdc to fan missing. or the wire fell off.
some cars have all this, my 96 does.
on newer cars the ECU can shut the AC down for many reasons.
most are related to safety to the driver, or Compressor.
for what reasons, only the FSM answers that , and varies
by year, engine type, model and country sold.
if in usa , you didnt say. then alldata dot com has these facts
and more , under section called HVAC.
The brain will not allow you to burn up the compressor or worse.
it tries very hard at that. even as old as 1991 cars. (some)
Oct 12, 2013 |
2008 Honda Accord 2.0i-VTEC