Too Hot, Too Cold, Just Right

We have a 96 Honda Odyssey van. I keep thinking of selling it. It keeps coming in handy. So now we have a van with more than 198,000 miles. Recently the van was too hot since the A/C stopped working. At 198,000 miles, stuff happens.

I took it in for repair and before the shop could find the root cause, the A/C spontaneously started to work again. Since it is hard to fix something that is not quite broken, the shop asked me to bring it back when it failed again. I agreed with their logic and appreciated their non-random methods.

It soon failed again just prior to when we needed the van and really, really needed the A/C to function. Since it failed on the Thursday before the July 4th holiday, the shop was very busy and not able to look at it until the following week.

We really needed the van, so I went for plan B. They shop had narrowed down the problem and well described what they had already checked, so I knew the A/C thermostat was the likely problem. Using Google, I found the electrical schematic for the A/C system for my van. Using the schematic and a volt meter, I confirmed that this A/C thermostat, located behind the glove compartment, had failed.

I called the local Honda dealer and they did not have the part on hand. So, I opened up the black box (it was not working anyway) as shown.

I was not able to tell what component had failed, so I soldered in a jumper wire (see below) to make the thermostat relay appear as always on.
It worked. We made the trip just fine, but it was too cold, which seems better than too hot.

I ordered and installed the new part this week and it now it is just right!

Rick