Aftermarket Radio and Keyless Entry
 

Hi all, thanks for any help you can provide.

I replaced the OEM speakers and head unit with a Kenwood unit recommended by Crutchfield. Now the ignition works strangely. Keyless entry works fine, but if i try to start the car with the keys in my pocket, it just beeps and the Keyless Entry light comes on in the dash.

If I hold the Key up to the start button, I can get the car to start, but the error light stays on and if someone opens and closes a door, I get a "No key" indicator with beeps.

Did the OEM head include some sort of antenna for this system, and if so, is there a way to make it work with an aftermarket stereo?

(I did put a new battery in the key fob just to check)

Take your stock radio and plug it in again (temporary), see if everything returns to normal.

That's good advice. I've been advised by my vendor that there's a problem with the batch of wiring harnesses mine came from, so when that comes in, I'll take it all apart and try the original radio again.

Look for blown fuses in all fuse boxes (there are at least 3)

"Back-up" fuse in engine compartment fusebox blown??

I tried re-installing the factory radio the other day - didn't have the keycode so Im not sure its a good test. I may have to go back in next week.

Checked all the fuses under the hood and under the dash that had anything to do with "back" or "Smart" and didn't find anything blown.

What is that? Radio unlock code?
Does the original radio have a touchscreen?
With the ignition powered up, just hold the radio power button down for about 3 seconds to unlock it.

If it does not have all of the correct power sources (i.e. blown fuse), the radio may not come on or may not unlock.


Is the car a 15 or 16? Trim level?

Since you only messed with the radio, I would only expect fuses blown that have to do with the radio.

here's the fuses I found to do with the audio system on a 2015 USA GK5 EXL CVT (without navi)

Battery terminal fuses A1 (100A), A2 (70A)

engine compartment box
b21 (15A)

Dash aux box d4 (30A) d1-3 (50A)

Dash fusebox c3 (10A), c34 (7.5A), c37 (7.5A)


I use a simple 12v test light for checking most of the small fuses, fairly simple and super quick. No fuse removal necessary.
I also tend to check ALL the fuses in a fusebox this way, without knowing or caring which fuse is used for what system...because so many systems use multiple fuses.
If/when I find a blown one, replace it, retest it, and keep checking the rest of them.


HTH

Thank you for the reply. I should have provided specs up front - it's a 2015 USA EX, six-speaker without Navi, so it's got the seven-inch OEM radio. Upon reconnect, it requires the radio unlock code, which I have not gotten from the dealer yet.

Thanks for the fuse suggestions - I will do that when the weather gets better.

The test light is a great idea! Do you unplug the negative terminal on the battery first?

It's very strange - the keyless entry works in that I can unlock the car remotely, but I have to hold the key right up to the ignition button to get it to start. The key error light stays on and if you open a door while it's running, the car beeps and a "No Key" light flashes in the odometer side of the readout.

I've never had to use a code to unlock one of those.

No code needed as long as the other necessary control units in the car power up. Just turn the ignition on (start the engine), hold the radio power button on for a few seconds and once the radio 'shakes hands' with the rest of the control units and decides it's still in the car it belongs in, it will unlock.

But the pushbutton start has to work correctly first....and it does not (and it shares at least one of the fuses listed previously), so the radio probably won't unlock. Once this is corrected, the radio would be expected to unlock electronically with the above method again.


Maybe you should google for some of the basics on how to use a 12v test light.

If looking for B+, the other end must be hooked to a ground. It does not have to be the battery post, as the entire car body is 'chassis ground'. Much of the visible bare steel under a dash will be a part of the ground.

Conversely, If searching for a ground with the test light, the other end would need to be connected to a B+ source.


Did you check the fuses I listed in the previous reply?

Hi there,

I have checked the fuses myself and had a Honda mechanic do it as well. They are all good. The mechanic theorizes that there is a part of the ignition system in the OEM radio itself, but he can't go to tech support above his level without making a ticket and charging labor.

Does any of this from the Owner's Manual apply to you?
https://i.imgur.com/UMDI96d.png (pg. 92)

I can't speak from experience, but I remember a post by DucktapeMaster saying he drove around without a Head Unit and had normal operations.

https://www.fitfreak.net/forums/3rd-...ml#post1324866

I'm looking into swapping my Head Unit too, so I'm interested in solving this.

They don't apply. There's no problem with keyless entry. It's only keyless ignition. I can lock and unlock the doors remotely.

This is not the case. The car should start and run without the factory radio connected, as someone else noted earlier (when everything else is working correctly)

I wonder if the mis-built aftermarket radio harness caused a communication network fault?
This could get expensive if it took out any control units.

Put the original radio back in as the factory built it, show up at the dealer expecting warranty to cover the pushbutton start not working right......and just play dumb. LOL

Wait, the dealer already knows your car has been messed with? OOoooh, that may hurt.

What was the resolution?

Solution!
 

User JimReeves found a solution! It worked for me and I've added photos. My own fault for not making sure EVERYTHING was plugged back in on the lower panel.

https://cimg5.ibsrv.net/gimg/www.fit...82ffb73f8d.png

https://cimg4.ibsrv.net/gimg/www.fit...14cccb39af.jpg