No power to the Climate control?

2012 HONDA ACCORD
130,000 MILES • 2.4L • 4 CYL • 2WD
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TYLER573
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Not too long ago I was trying to replace my radio and accidentally cut my climate control head unit wiring harness instead of the radio harness. I’ve gotten it rewired and I’ve checked all the fuses and relays and there is still no power to the climate control head unit.
Dec 13, 2022 at 11:42 PM
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STRAILER
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We need to test the power at the climate control head pin # A9 lt/green wire with the key on. Also check for power at fuse #16 7.5 amp at the under-dash fuse panel left kick panel.

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Here is a guide to help and the climate control wiring diagrams so you can see how the system works in case you need them. Check out the images (below). Please let us know what you find. We are interested to see what it is.
Dec 15, 2022 at 11:49 AM
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TYLER573
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So, I’m getting a 4.8 reading back from the #16 fuse but no power from pin #19.
Dec 15, 2022 at 2:39 PM
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STRAILER
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My bad, I made a correction its pin A9 on the climate control unit, it should be 12 volts, key on. So, you are getting 4.8 volts at the fuse #16 on the drives side fuse panel (behind left kick panel) correct? This fuse is powered by the ORG wire that comes from the ignition switch. Let's double check the voltage at fuse 16 before we replace the switch. Here is how to replace the switch in case you need it. Check out the images (below). Please let us know what you find.
Dec 16, 2022 at 11:31 AM
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TYLER573
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That is a guide for changing the ignition switch ???
Dec 16, 2022 at 9:27 PM
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STRAILER
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Sure is, did you re-check for power at fuse #16?
Dec 17, 2022 at 1:51 PM
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TYLER573
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I did and I’m still getting 4.8 still no power at the harness.
Dec 17, 2022 at 8:26 PM
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TYLER573
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I forgot to mention that the 12v charging ports are also out they won’t charge or power anything.
Dec 17, 2022 at 8:27 PM
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STRAILER
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With the key on please test the red wire coming out of the ignition switch, it should be 12 volts. Let me know.
Dec 19, 2022 at 1:12 PM
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TYLER573
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I am getting 12v from it.
Dec 19, 2022 at 8:30 PM
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STRAILER
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Okay, are you getting 12 volts at pin A9 on the climate control unit? If so, we should confirm the HVAC controller failure by doing a CAN scan which is easy, you can get a CAN scanner (Controller Area Network) from Amazon from about $32.00. here is a video to show you how. Also check the ground b4 which is behind the middle of the dash.

https://youtu.be/u-4syLc-ifQ

and

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Amazon CAN scanner link:

https://amzn.to/3sX8MCX

Here is how to change the HVAC controller out in case you need it. Check out the images (below). Please let us know what you find. We are interested to see what it is.

Dec 20, 2022 at 11:53 AM
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TYLER573
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Okay, so I made a mistake I’m getting 58.2v from the red wire on my ignition switch.
Dec 20, 2022 at 3:02 PM
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TYLER573
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But still no power from pin 9 on the harness.
Dec 20, 2022 at 3:04 PM
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TYLER573
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When I test the head unit in this video it gives me a 10.88v reading.
Dec 20, 2022 at 3:20 PM
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TYLER573
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And now I’m not getting any voltage from the #16 fuse but it isn’t blown.
Dec 20, 2022 at 3:38 PM
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STRAILER
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Double check the voltage reading and if none the ignition switch is bad, or you have a short in the wiring. You can use the wiring diagrams in my first post to check the connections and see how the system works.
Dec 22, 2022 at 2:16 PM