i recently had an a/c guy recharge the maxima with r-134a but the compressor refuses to turn on. he says with enough r-134a the compressor should turn itself on, but without pressure, it turns itself off. he also said i might just have to knock it since its been still for so long. he put in one can of refridgerant, and claimed that should be enough to kick the compressor on. to my knowledge i dont have a leak and the fuses look intact. the fan blows air as well. does anyone have any ideas before i pay the shop to fix it? it hasnt worked since last year (heater too) but ive been at the naval academy where we cant drive anyway. thanks for the help

Mike

 

Well first of all, unless you have repaired it, you DO have leak. Why else would you need to add refrigerant?

If you are confident that the system is properly charged, then use a jumper wire to engage the compressor clutch. This will tell you if the mechanical portion of the system is OK. Then it is on to sensors, switches and such.

 

can you elaborate i only have an idea of how to do that. it is my understanding the a/c has never needed a recharge before this but i see your logic

 

The compressor has a one terminal connector wire running to it. This provides 12v power to engage the clutch.

Simply disconnect this wire and run a jumper wire to the connector on the compressor, before starting the car. Then after starting, attach the other end to the positive terminal on the battery. This will require about 3 feet of wire, BTW. Your clutch should now engage and you can tell whether or not you have a functioning compressor.

AC gages hooked up to the system while doing this would also be a good idea. You could then monitor the system correctly. You should have around 70-80 psi on both HI & LO sides before starting the engine.

 

I agree^ jump it, if it's ok check sensors, and connectors- you said ur heater doesn't work, so after checking the mechanicals check ur switch (a/c panel inside) if u did anything with the radio u probably left a loose plug or swith may be defective though rare, heater doesn't run with comp on, it uses engine heat, so check the switch if the comp clutch engages---> overcharge may b a possibility.