Car Air Conditioning not Cooling well
In this diagnosis case series lies my recent troubleshoot and resolution of poor cooling from the air conditioning (AC) on a friend’s 2003 Toyota Corolla. Regardless of car make or model these steps will work in other vehicles with an AC system that isn’t cooling enough. Problem: the basic complaint from my friend was that passengers often complained of the AC not being cool enough despite being on max. The car was purchased used and the poor cooling had been observed right after purchase.
Troubleshooting and Resolution: When a car’s AC system isn’t cooling enough, one of the first things for the DIYer to confirm is if the compressors cycles on and off as designed. On the index car, the compressor cycled well. Also confirm that the blower works (i.e air comes out of the AC vents)
With both ruled out, I always recommend checking the state of the cabin air filter. This is a good step to tick before checking the charge on the system. Most cabin AC filters are located behind the glove box. To access it, open the glove box, then holding the 2 side walls of the compartment, compress i.e. push both sides to each other. You may need to unhook hinges (depends on car make) for the glove box door to drop out of the way. Once done, the cabin filter will typically be behind a cover that will be opened by depressing 2 locking tabs on either side of the cover.
Location of the cabin filter
Once I opened the cover to the recess housing the cabin filter, I needed no one to tell me what the diagnosis was….A clogged cabin filter!!!
Cabin air filter on 2003 Toyota Corolla
The magnitude of the problem…
Diagnosis: Clogged cabin filter!
A simple change and the AC chills like winter! And my friend wouldn’t stop talking 🙂
New cabin filter going in!
Where the cabin filter isn’t clogged attention should be turned to the level of charge in the system. Either a low or an over charge can cause poor cooling. A clogged condenser can also cause poor cooling. I found this resource from certifiedmastertech.com a good one in troubleshooting poor cooling and would gladly recommend.
Happy new year!!!
Good morning,
how do i check the level of charge in my AC cooling system because my AC still isn’t cooling well enough?
Hello stec,
Happy new year to you!
To check the level of charge in your system you will need an AC gauge or manifold gauges. This will be attached to the low side of AC system port (usually marked “L”) and will read the actual psi of the charge in the system just like the psi of air in a tire.
However, the reading obtained is dependent on the ambient temperature, meaning that depending on the temperature of the environment at the time of reading, you will get different levels of psi (charge).
Thankfully, there are charts available for free online that list the correct pressure reading of the low side at different ambient temperatures. In the link below check the reverse side of the can to see a sample of this chart. Remember that an over charge can also cause poor cooling. I hope this helps. Do fee free to call back should you need further assistance.
http://www.amazon.com/gp/product/B001810SHA/ref=s9_simh_gw_g263_i3_r?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=desktop-1&pf_rd_r=07A500TXTQ5NR783QYPD&pf_rd_t=36701&pf_rd_p=2079475242&pf_rd_i=desktop
In addition to the above, some other practical ways where there’s no manifold gauges:
1. The low pressure piping in the engine bay should feel very cold when your AC has been running for a while.
2. In combination with 1, does a mist come from your vent(s) especially in the evening or early mornings with the AC in vent (as against recirculate)? These are suggestive of a low charge.
Good Morning Piyke,
I would like to know the procedure for checking to know if your cooling system is low on charge? I believe i have done what you have said so far but still feel my AC can chill better than it is doing now. How do i check the level of charge in the cooling system?