Ac and recirculation buttons flashing?

[JASON SHIMKUS]

Hello all! I'm new to the forum as my 2012 1500 is my first truck I've owned. I'm having an issue with my ac. It intermittently goes out. When it's working it blows ice cold. But when it's not, and this is really weird as I've never seen this before in any vehicle I've owned, the AC light and the recirculation lights flash fast, even with the engine off and the key out of the ignition. I've checked all the fuses and they are good to go. When I turn the AC on I hear the click at the relay but the clutch on the compressor won't engage.

This has happened twice before but only laster for a day or two. Yesterday is now the third time. Also when this happens, the auto headlights don't work. But as soon as the AC starts working again, the auto headlights work again too.

This is totally odd behavior. Like what does one thing have to do with the other. Anyone ever experience this that can enlighten me on the problem? Anything mechanical I can fix myself, but with all the computers wired into everydamnthing nowadays, it's a lot more difficult to diagnose this stuff!

Also I check all connecting points for the AC system and there are no noticeable freon leaks, although I haven't tested that yet.

Any help would be greatly appreciated! I hope to pay it forward someday being new here!

Edited to add. Just noticed while driving at night, everything on the dash and radio is illuminated except for the heat/ac controls.

 

[meedom]

First thing have your battery TESTED at Auto Zone or O'reillys before you go any further.....

 

[madtrucker2016]

ground problem or check the battery might be a problem

 

[JASON SHIMKUS]

Well I had the battery and alternator tested and they both tested out fine. I've searched Google about this but could not find anything specific to this issue.

 

[indept]

Well I had the battery and alternator tested and they both tested out fine. I've searched Google about this but could not find anything specific to this issue.

Sounds like it's a connection or ground issue. You need to find schematics for your truck and find what modules are common between AC & headlights. There is someone in this forum that had a thread with those schematics. I'll try to find it.

 

[Tach_tech]

Usually if the lights on the HVAC controls flash it is due to the control head has detected a fault.

A scan tool that can read the HVAC module is going to be the best bet.

 

[JASON SHIMKUS]

Sounds like it's a connection or ground issue. You need to find schematics for your truck and find what modules are common between AC & headlights. There is someone in this forum that had a thread with those schematics. I'll try to find it.

Well as crazy as this sounds, I was messing with the fuze box(TIPM), I pulled the biggest relays out, the 2 in the center top. I started the truck and it started fine. Turned the truck off. Installed one of the relays. Started the truck again and the AC clutch engaged immediately. Turned the truck off and put the other relay in. Started the truck again and the AC still engaged. I put a towel over the auto headlights sensor and the headlights turned on.

What stumped me about this...the fuze panel that shows what everything is...does not label those relays with anything AC related. Otherwise I never would have posted here because that was the first thing I checked. Now I know. But I wanted to report back in case anyone else has a similar issue as I found this forum on a Google search.

 

[meedom]

Really appreciate your sharing that sir instead of leaving us all hanging like some do.....

 

[JASON SHIMKUS]

No problem. I couldn't find anything about this anywhere else on the net so hopefully this thread pops up on a Google search for someone else having the same issue