cal45fan

My 01 Civic has no AC! I replaced the OEM AM/FM radio with an OEM CD Player. To replace the radio, I removed the AC panel along with the dials and switches for the HVAC. I put it together after the radio has been replaced. Radio works but the AC button will not light up. The Recirc and Defroster buttons work.

I looked for the fuse that controls the AC but I could not locate it. All I found were the relays that control the AC system under the hood. I swapped them out with the other identical relays and still nothing. I went back in the AC panel to double-check my connections and re-plugged everything in. Still nothing.

I had an AC indie check pressure in the system and he said there is pressure on the high side. He cannot check the pressure on the low side because the AC clutch will not engage.

I shorted out low pressure switch connector on the diver side of the radiator , started the car up, turned on blower and pressed the AC switch. Still nothing.

Did I miss anything? Is there a hidden fuse for the system? Where do I go from here?

Please

ezone

You can't jump the pressure switch and expect it to work, the system does not work that way.

Pull the HVAC panel out and leave all the wires connected....

Make a jumper wire with a unbent paper clip on one end, connect the other to a ground....

Start the engine up....

Stuff the tip of the paperclip into the back of the connector (touch the metal to make a connection) to ground the blue wire in the connector A-4 on the control panel. See if the AC runs now.


If the AC runs now, then that rules out a lot of stuff, the problem is down to the HVAC control panel area.


EDIT: Don't do this unless you know what you are doing! I'm not taking the blame for "accidents", I'm telling you what *I* would do to check this.

lazlong

Connector A is a 14 pin connector

cal45fan

I read another thread of "AC Not Working" and the culprit was blamed on the 'multiplex'.

http://www.justanswer.com/honda/3lpu...-fans-not.html

What is a multiplex? Is this the fuse box underneath the steering wheel? If so, are the wires (harnesses) directly connected to the HVAC panel from this multiplex?

Thanks.

ezone

Multiplex unit, or MICU, is a body computer. It is built into the dash fuse box.
It has some control over the AC system, but only a couple of functions. It does have the ability to shut the AC down or keep it from operating.

It does not control the lights on the buttons.