Troubleshooting NB air conditioning

timk · Postby **timk** » Fri Jan 24, 2014 9:46 pm

Hey guys,

The air conditioning button in my NB isn't doing anything, but the fan/blower still works. If I pull 1P low on the ECU (air conditioning request) then the system works, but it runs 100% of the time as it has no feedback from the evaporator temperature sensor, or the refrigerant pressure switch.

Here is the schematic:

Is anyone an expert on the system? Any known weak/failure points?

I guess it has to be one of those two sensors or the amplifier (whatever that is), unless anyone has more clues?

I'm a bit of a noob at this kind of thing!

Cheers

MrRevhead · Postby **MrRevhead** » Fri Jan 24, 2014 9:54 pm

Get a leak test, check your pressure sensor and also evacuate/pressure test the gas to see if you have enough in the system. If you're low in gas, the pressure sensor reads and does not let the compressor clutch engage to compress air. If so, refill with a dye, monitor and check for leaks if the problem occurs again in the future.

sabretooth · Postby **sabretooth** » Fri Jan 24, 2014 9:54 pm

As on IRC - my guess is the thermostat. If the thermostat reports too cool then it won't turn on.

MrRevhead · Postby **MrRevhead** » Fri Jan 24, 2014 9:58 pm

IRC.....what server & channel are you guys on?

I was an active IRC user from 95-2010, but left thinking many gave up on it, lol

I know you guys were once/maybe still are old OCAU users lol

timk · Postby **timk** » Fri Jan 24, 2014 10:06 pm

MrRevhead wrote:IRC.....what server & channel are you guys on?

#mx5 on oz.org.

NMX516 · Postby **NMX516** » Sat Jan 25, 2014 9:27 am

Yep, as MrRevhead said, if the gas has leaked out, the compressor won't turn on. Does the idle increase when you switch it on?

timk · Postby **timk** » Sat Jan 25, 2014 6:39 pm

NMX516 wrote:Does the idle increase when you switch it on?

Nope, and the switch isn't flipping the input to the ECU either. The system has been regassed recently so I'll start by swapping out the thermostat with another one.