ac not working in 04 buick rainier but it appears to have a full charge
what does the pressure gauge read at idle high side and low side?
You can bypass the compressor relay by pulling the relay and putting in a jumper wire.....this should get the system working so you can get pressure readings. There are high and low pressure switches built into the system and if they are bad or giving a bad reading the ECM will not turn on the relay to start the compressor.
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