Recently, in my 2017 Chevy Trax, the AC air wouldn’t come on for 10 or so minutes but would come on eventually. And once it came on, it would stay on. Now, it won’t come on at all. There will be a 5 sec time where the air would come on but ever so faintly.

I’ve changed the air filter, I’ve changed the blower motor. I cannot isolate the problem. The fuses seem to be fine. I need help locating the problem in order to fix it. Please help.

The blower won't turn on? . . . or the AC won't turn on?

"fuses seem to be fine" can mean a lot of things. Have you checked fuses with a volt meter set to continuity?

The blower won’t turn on. And it’* a new blower motor. I will feel very cold air for about 5-10 seconds after driving for quite some time but it is very faint, like fan speed 1 type flow.

I have not actually checked fuses with a volt. But to be fair, I’m not sure at all on how to read the meters either.

I think that'* the next step, or at least check for 12V on both sides of the respective fuses.

I believe what you are looking for are fuses F21 and F23 and relay RLY04 in the instrument panel fuse block.

From your owner'* manual:




I circled the section that I think you need to worry about. Without a meter and without knowing how to use a meter, here'* what I'd do:

1. Pull fuse F21, does it look burned in the middle? If yes then proceed to step 14 and if no then reinstall and proceed to step 2.

2. Pull fuse F23, does it look burned in the middle? If yes then proceed to step 14 and if no then reinstall and proceed to step 3.

3. Using your thumb, press on relay RLY04 with a few pounds of force. This would be about the same amount of force as your thumb feels when squeezing one of those black binder clips that hold stacks of documents together. While pressing, wiggle your thumb around a bit like you're trying to squash a bug really good. Stop pressing. Try the blower again. Did this help? If yes then replace and proceed to step 16 and if no then proceed to step 4.

4. Look at the top of relay RLY02 to understand which way it is oriented. There should be text or something there to allow you to tell which way it plugs into the terminal.

5. Look at the top of relay RLY04 to understand which way it is oriented. There should be text or something there to allow you to tell which way it plugs into the terminal.

6. Carefully remove relay RLY02. Don't get it mixed up with the other relay.

7. Carefully remove relay RLY04. Don't get it mixed up with the other relay.

8. Compare RLY02 with RLY04. Do they have the same number and orientation of metal pins? If yes then proceed to step 9 and if no then proceed to step 12.

9. Install the relay that you removed from RLY02 into the terminal for RLY04. Does the blower work properly now? If yes then you have learned that you have a bad blower motor relay, proceed to step 17, and if no then you have learned that the blower motor relay is probably okay.

10. Install the other relay that you have removed into the terminal for RLY02. Does the liftgate work properly? If yes then you have learned that the blower motor relay was fine, and now you have promoted the blower motor relay to liftgate relay.

11. Go to step 19.

12. Replace both relays back where they came from.

13. Go to step 19.

14. Replace this fuse with another fuse of the same type and rating. Did this help?

15. Go to step 19.

16. It looks like the relay shook loose a little bit or otherwise had bad contact. Moving it around a tiny bit appears to have solved this. Proceed to step 19.

17. Replace the other relay with a new equivalent relay. Does the liftgate work properly now?

18. Go to step 19.

19. End.