So the A/C suddenly quit in our 2004 Honda Odyssey.

When you set the controls to 'auto', and start the van, you hear the A/C compressor momentarily engage for about 2 seconds, then disengage.

I assume something is wrong with the relay that controls the A/C clutch... or possibly some breaker is being tripped by a short, causing the compressor to disengage.

Now, my question is... WHERE ON EARTH IS THE A/C CLUTCH RELAY?

I looked in all the fuse boxes I could find... nothing.

There are 2 unlabeled relays in the engine compartment, but it looks like they're connected to the starter.

Anyways, any help in the matter is appreciated. It's quite hot in Alabama, and this whole no A/C thing is a real problem for us.

 

First thing you always check is pressure in the system, if the compressor comes on the most likely the relay is not the problem. It also does not have two relays for the starter so very likely they are related to the fan or compressor. You need your own repair manual with a wire diagram if you are going to work on your own vehicle.

A little relay operation theory, it takes a good amount of power (amperage) to pull a relay closed, but it only takes a little power (amperage) to hold it closed, so since your relay is working for a couple of seconds, I dont think it is the problem. Relays can be bypassed (jumpered) to see if the problem lies elsewhere, although it is possible that the coil side of the relay, the control side may be loosing its signal but that is outside of the relay, its power source or its ground, again, the relay can be bypassed to show if there is a problem with something else. Get a pressure gauge set (autozone rental) and a wire diagram, even check your local library for Haynes manuals. You simply may not have enough freon to keep the pressure switch closed.