Hey guys, new to these forums, and I am starting off by posting a question that I couldn't really find the answer to anywhere.

I have an 04 Civic SiR that came with an aftermarket radio in it. From what I understand in the Si's for this generation, they still wire the antenna through the OEM head unit, so right now my keyless entry is not working. Is this the case, or am I getting some wrong information?

Is there anyway to bypass this system like buying an aftermarket antenna and wiring it to the original wire that is not plugged in right now? Or do I really have to buy a new radio and stuff it behind the after market one (or just putting the stock one back)?

Thanks

Keyless is completely independent of the radio in that car.

Double check that your fob is actually correct for the factory keyless system (post a pic?) and the red light comes on when you push buttons on it.

Try the DIY transmitter programming (search for it)

I have 2 fobs with FCC ID: NHVWB1U521 that worked before the radio was installed according to the previous owner. Red light does come on when pressing unlock/lock, I even tried buying new batteries to rule that out.

I did try programming it a bunch of times but I get no results.

Do you know where the device is located that receives the signal from the transmitter?

I have a diagram of the hatchback SI body (USA version) showing it below the right side of the gauge cluster.
(not in the same place as a sedan or coupe of the same year and I didn't see a good pic of the location in google images)

has a 5 pin connector with 4 wires in it.
Maybe half the size of a pack of smokes.




Engine compartment fuses # 7, 9, 16
dash fusebox # 10

ANY other weird electrical problems going on? Beeper inop? AC inop? Dome lights don't work right?

Thanks for finding out where it is, I guess I would have to take apart the dash to find out if it's a problem at that end.

I have checked the fuses quickly today but not thoroughly, so I will get back to you on that note, but nothing really out of the ordinary when it comes to electrical problems. Beeper works, ac works, dome lights work perfectly. The only thing that died on me but was working, is the passenger locks won't unlock when hitting the inside switch but that was slowly dying and is most likely the actuator as you can see it try to move up the slightest bit.

Sure, weak/bad actuators are common.

Is the drivers actuator bad too? Does it not work with the switch on the driver door?

Yeah I heard they are common. The driver side is working perfectly

If you can locate the keyless receiver, the 4 wires would be

(black) ground
(blue/orange) data communication to the multiplex unit in the fusebox
(yellow) keyed power
(empty)
(white/red) battery power

Connector is green

The regular Civics sometimes had issues with the multiplex unit, I don't think I've seen enough of the hatchback SI cars here to know if they had the same issues.

If you lock the doors then repeatedly push the lock button on the remote, will the horn beep?