Toyota Tundra Forums banner

1 - 6 of 6 Posts

·
Registered
Joined
·
138 Posts
Discussion Starter #1
My AC will work fine for a week or so and then out of the blue quits cooling. This usually will last a day. Cutting off Ac and back on, shutting off ignition, or not cranking for several hours has no effect. Crank the car the next day and have cold air for a week or so again. Already had coolant level checked. Any suggestions?
 

·
Registered
Joined
·
910 Posts
Could be many things...but let's start with the basics.

1. When you turn on the AC (and it's not blowing cold), is the compressor kicking on. You can usually hear a "Click" sound and notice a change in the engine idle. If NO, then it could be a low system charge, or more specifically, a charge that is just low enough that when the ambient temp drops, the pressure in the system will drop just enough to not let the system turn on and vice versa when ambient temp goes up.

2. Assume a NO to number 1, the cause could be a faulty pressure switch. Verify the connection is good. The switch goes to continuity between 28 and 455 psi.

3. If/When the compressor does kick on, look at the site glass on top of the receiver/dryer. Is should be clear when the system is running. If you see bubbles in the glass, it usually indicates a low charge.

4. You could have trash in the expansion valve that sometimes restricts proper flow and cooling.

There's a ton of stuff to check. It's really about isolating a specific component using a decision tree then troubleshooting. To do it right, you need a set of gauges. If you can figure out the answer to Q1 above, we can give you more direction.
 

Attachments

·
Registered
Joined
·
138 Posts
Discussion Starter #3
Thanks for the response. I will check out when it quits cooling again. Could it be something electrical. Talked w/ my stereo installer. There is a sirius box and bluetooth wired and cramped in space behind center console. Wonder if him being back there could have anything to do with it, ie loose connection, etc...
 

·
Registered
Joined
·
910 Posts
Thanks for the response. I will check out when it quits cooling again. Could it be something electrical. Talked w/ my stereo installer. There is a sirius box and bluetooth wired and cramped in space behind center console. Wonder if him being back there could have anything to do with it, ie loose connection, etc...
Possible but not likely. If it is cooling right now, go look in the sight glass on the receiver/dryer. That will give you some idea if the system is adequately charged.
 

·
Premium Member
Joined
·
66 Posts
My AC was acting the same way. After weeks of trying everything, I remember this problem began after I installed my new head unit. It turns out that the harness on the reverse side of my AC button/switch had a loose connection. Must of jacked it when I installed my new stereo . When my the circuit was opened the cold air would stop. Check your harness behind the AC light.
 
1 - 6 of 6 Posts
Top