The AC is fully charged, but the compressor will only kick on if I connect a jumper wire from the battery- (THEN it cools great) What is the most likely culprit ?
ANY ADVICE WELCOMED !
Signed, Melting in Louisiana :help
'93 Infiniti J30T AC Compressor won't kick on
Yeah, you can't remove the switch without releasing all the refridgerant. Do you have R-12 or R-134a? Not sure what year they actually switched over. You can get a shop to recover either one for free. For R-134a you can recharge it on your own; R-12 will cost a lot more. Before opening it up, get an ohmmeter on the switch harness and check for continuity. If there's continuity then the switch is probably fine. By opening up the system you're committing to replacing the drier too. Have you checked the relay and whether there's power to it with the AC on?
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Q451990
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Luckily I haven't had too much experience with the Q's airconditioning system - :xfingers but I just did a major overhaul on my truck.
On the truck you have to have good readings from each of these sensors for the the ECU to send the ground signal to the relay.
Pressure sensor: Has to read between certain PSI readings. No or low freon will keep the compressor off.
Compressor Temp. Sensor: Mounted in the case of the compressor housing. If the compressor overheats, the ECU turns it off.
Evaporator Sensor: Mounted in the fins of the evaporator. It opens up when the evaporator get's too cold and is in danger of freezing up.
I don't know if these sensors are on the J's system or not - but they're things to consider. You should be able to check them out with a mulit-meter.
I think the ECU also has to sense that the interior blower motor is on before the compressor will engage too.
Heath
On the truck you have to have good readings from each of these sensors for the the ECU to send the ground signal to the relay.
Pressure sensor: Has to read between certain PSI readings. No or low freon will keep the compressor off.
Compressor Temp. Sensor: Mounted in the case of the compressor housing. If the compressor overheats, the ECU turns it off.
Evaporator Sensor: Mounted in the fins of the evaporator. It opens up when the evaporator get's too cold and is in danger of freezing up.
I don't know if these sensors are on the J's system or not - but they're things to consider. You should be able to check them out with a mulit-meter.
I think the ECU also has to sense that the interior blower motor is on before the compressor will engage too.
Heath