# 2004 Nissan Altima-A/C relay



## redsradiatorspec (Jun 5, 2013)

Working on a 2004 Nissan Altima A/C system...assuming it is a relay issue but cannot locate the relay.....anyone know why I'm not getting power to the compressor??


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## smj999smj (Jan 1, 2006)

The A/C relay is in the IPDM/ER behind the right side headlamp in the engine compartment. There are a lot of things that can cause the compressor to not engage. Most common cause is low freon in the system, which is sensed by the A/C pressure sensor. The IDPM/ER controls the A/C relay. Its CPU receives inputs from the pressure switch, ECM and HVAC control head to determine when to send power to the A/C clutch assembly. You can try swapping out the A/C relay and see if it corrects the problem. If you don't have one, I would recommend you download a copy of the Nissan FSM for your Altima and follow the diagnostic procedure for you problem if that doesn't work and you've checked all of the fuses. If you don't have an R-134a gauge set, a scantool and a multimeter, it's going to be difficult to diagnose the problem.


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