Hello there,



During the summer on especially hot days, the A/C would not kick on with the car. If I let the car sit in the shade for a few hours, it comes back on by itself. It didn’t happen frequently enough for me to be concerned, so I didn’t work on it. Now that we’re getting to the colder months, I seem to be having an issue with the heat not coming on at all. Any ideas where to start?

To clarify, both the fan and the compressor seem to have a hard time getting started on exceptionally hot days (I live in Central FL).

 

Ok so the first things I always recommend...
Have the battery load tested.
Age, when you bought it or brand has nothing at all to the current condition of the battery!

This means that the battery must be at least 12.5+ volts to do a proper load test.

Many automotive parts outlets offer this for free.

Then check the terminal connection on the battery as well and maybe more important is the ground cable to the chassis and the positive cable to the starter.

After that report back and we can move to the next things.

 

Hello there. Thank you for the advice. Sorry for the delayed response. There has been an update. The fan does not turn on now, regardless of temperature. I can hear the compressor turning on, and feel cool air slowly pouring from the vents when the car is moving, so I am certain it is an issue related to the fan itself.

Two different shops got a “bad battery” reading. One of the two was able to tell me the battery is rated for 14v but is reading 12.5v and is not at optimum capacity. The one with more info told me he didn’t believe the issue with the AC/Heat has anything to do with the battery. I only mention that to say I don’t think that he was trying to sell me a battery. What do you believe my next steps should be?

 

Ok so back to my first response.

If what I am reading is somewhat accurate your battery is not being tested properly????
I suggest going to your local Pep boys auto parts or better yet Firestone or both and having them "LOAD TEST" the battery properly.

Your information about the results is not exactly what I would consider useful
However, if what I think is a bad battery then that must be replaced first. But I am going to repeat RE-READ my first response and adhere to the recommendation..... completely


Maybe next time you have some in a shop look at your Mazda see if he has an ASE patch or bottom on his/her shirt or is certification hanging in the office area.
If a Mazda dealership, service department then that would be a Mazda Certified Trained Auto Technician.

ASE

 

I have attached the results of the test that Firestone performed on my battery. I was very specific to ask for a “battery load” test.


I am seeing that No-load current and Load current are void of data. Did they not perform a part of the test?

 

The first section is accurate, and you have a battery that is in state of failing.

Further testing is not really required or needed at that point of testing! But it indicates the charging system is working.

I can tell you with winter temperatures if you do not replace your battery better have that AAA membership up to date. At some point unexpectedly (if you disregard replacing your battery) you will get a no start engine.

As well until you replace your battery and follow the rest of my first response anything connected to the electrical system and diagnosing a problem is negated until you get a new battery!

 

I just installed a new battery. What should my next diagnostics steps be?