A/C unit not working properly

2003 HONDA ACCORD

16,878 MILES • 3.0L • V6 • 2WD • AUTOMATIC

FRESH8400

MEMBER
1 POST

Replaced heater core, condenser, seals (rubber rings) all of them, power transistor, AC unit (compressor) AC Freon and a radio with same plug in (upgraded). These things need replaced, I'm getting warm air, no cold or/and fresh air and no power to compressor. Do you think I may need blend motors (2) fuse and Relays? I know there is one relay under hood. Please and thank you.

Mar 22, 2022 at 2:05 PM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

The blend door motors are not going to cause no power to the compressor.

So, we need to find out if the compressor is able to function by jumping 12 volts to it. You can do this by removing the relay and jump pins 4 to 2 and the compressor should come one with the engine running.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

If it does, then we have to find out why the relay is not being commanded on.

We do this by checking power at pin 1 and 4 which should be 12 volts.

Then we need to check pin 3 for ground when the compressor is turned on.

https://www.2carpros.com/articles/how-to-check-wiring

If this all checks out, then we need to check the pressure in the system because it may be under charged causing the pressure switch to prevent the compressor from coming on.

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Please run through this and let me know what you find. Thanks

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Mar 23, 2022 at 5:46 AM

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