Troubleshooting a 2003 Honda Civic Air Conditioner
- 1). Inspect the fuse box (under driver's side dashboard) for fuses that may have blown. Read the instructions on the inside of the panel how to locate the fuse connected to the A/C system. If the thin metal strip inside the glass fuse is damaged, or broken, replace it with another of the exact same amperage rating.
- 2). Test all the A/C buttons and dials (with the engine running) for damage or resistance. Ensure that you have the air conditioner turned on and not just the electric blower fan. If you do not hear the fan start, a fuse may have blown, or the fan may need to be replaced.
- 3). Check under the hood (with the engine running and controls set to high) to see if the magnetic compressor clutch is operating correctly. Wait until you see and hear the clutch kick on. If it does not start, the A/C system may be low on refrigerant. Feel the drive belt attached to the compressor for looseness and ensure that that the A/C hoses and compressor are free of leaks.
- 4). Check the A/C system for sufficient pressure. Attach the color-coded compression gauge hoses to the system, with the blue hose connecting to the low-side port, and the red hose connecting to the high-side port. If the pressure is not somewhere between 50 PSI (Pounds Per Square Inch) and 80 PSI, have a mechanic investigate the system further for you.
- 5). Start the engine and look under the hood for the two hoses connecting to the firewall. The hoses are about the thickness of a garden hose and both of them should be warm to the touch. However, one should be noticeably cooler than the other. If it is not, the valve control may need to be replaced. Have a mechanic fix this for you.
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