E46 M52TUB20 ac issue - ac compressor not getting power.

[Arata 30]

Hi team. Dealing with my E46 hvac today. 
Basically the ac is not blowing cold, not even warm cold. Heater is working fine as well as blower blowing all speed.

i have checked the fuses and they are fine and getting power, checked the relays behind fuse boxes and they are ok too. Now only thing is that the ac compressor connector is not getting power when the button is pressed. When I press the button the engine rpm changes, so I’m assuming that the modules are telling to the ac compressor to engage the clutch but no power. I’m assuming that the ac clutch is gone and needs new compressor. But I’m just wondering what’s preventing it from not sending power to the compressor, is it because it’s in the fail safe mode that the modules are not sending power on purpose, or I do have wiring issues?

I have tried using the ac recharge can but according to the can and with the gauge telling me, unable to recharge as showing on red warning zone (70psi at low pressure) at needle pointing when the car/ac is on. Haven’t got to test the high side. What’s everyone’s suggestion? Thanks in advance.

[Eagle 1662]

So you are saying you pulled the compressor plug and have no power when pressing the A\C button?

You can manually test the clutch by applying 12V. If its not working then you either try another clutch from a wrecked unit or another compressor.   

[NZ00Z3 187]

Have you checked the operation of your electric radiator fan.  It should start for a second or 2 every time you start the engine.  The DME records the success of the start and uses it as a pre-condition to starting the A/C compressor.  If the fan is faulty, then no A/C.

[Arata 30]

On 12/30/2023 at 6:38 PM, Eagle said:

So you are saying you pulled the compressor plug and have no power when pressing the A\C button?

You can manually test the clutch by applying 12V. If its not working then you either try another clutch from a wrecked unit or another compressor.   

Hey Eagle, happy new year. 
That is correct, when the car is on and when I press the air con button on (or off) there’s no power at the compressor plug.

Ok that sounds like another thing I’ll try. Thanks for advice.

[Arata 30]

On 12/31/2023 at 7:37 AM, NZ00Z3 said:

Have you checked the operation of your electric radiator fan.  It should start for a second or 2 every time you start the engine.  The DME records the success of the start and uses it as a pre-condition to starting the A/C compressor.  If the fan is faulty, then no A/C.

Are you talking about the condenser fan? It is working as far as I know. I’ll give another look for the fan operation.