2004 EX-L w/ RES, want nav prompts thru spkrs using OEM signal/mute

[volvofan]

Hello everyone, this is my first post on this forum. Thanks to all for the great info provided (I've been lurking for a while and have found answers to a few questions about previous issues). For this issue, however, I've run out of places to look for the answers (both here on this forum and elsewhere) so I'll give this a try:

As stated in the title, my wife has a 2004 Honda Pilot EX-L with Rear Entertainment System. Looking at various pinout diagrams on this site and others (Crutchfield), I can see on the 20-pin blue connector that there are unused pins for the RES model that are utilized when NAVI is connected. There are two for audio input and one for muting. I am hoping that I can connect my dash-mounted GPS audio out (via an auto-muting circuit) to these inputs on the OEM head unit in order to hear GPS commands via the stereo. Aside from the overall "is this even possible and/or has anyone done it" question, I have two particular questions (assuming that it can be done):

1) Is the Navi mute a "grounding" mute or a "hot" mute, i.e. does it mute the head unit when grounded, or when some voltage or other signal is applied? I do NOT think that it is a grounding mute (although that was my first suspicion) because I did attempt to ground the pin to chassis ground and it seemed to have no effect on the radio.

2) Is the audio input from the nav unit into the head unit line level (i.e. already amplified) or low level (i.e. RCA inputs, headphones, etc)? I presume it is mono.

One unrelated question, but perhaps one I can get answered enroute - where did honda-pilot.org go? I see many links and references to threads and files on that site, but it appears to be no more. Any idea if those topics / knowledge bases got moved elsewhere or if they are gone for good?

Thanks in advance for any help you all may be able to provide.
-Jon

[rocky]

Honda North American lawyers callously took action against the forum resulting in our having to give up the hondapilot.org name. If you find a link with that in it and substitute piloteers.org, you'll find the thread you need.

[volvofan]

Originally Posted by rocky

Honda North American lawyers callously took action against the forum resulting in our having to give up the hondapilot.org name. If you find a link with that in it and substitute piloteers.org, you'll find the thread you need.

Sorry to hear about that mess, but good to know that noobs like me can still find info in linked messages located w/ the search feature.

One question answered... two to go! Anyone w/ NAVI who can chime in on the others? Thanks!

[rocky]

Thanks for posting back up. Try thumbing through this rather large thread to see if Edog did what you are looking for. Its one of the best out there.

Vizualogic / NAV A/V Switch / DVD Changer Installation Instructions

[volvofan]

Originally Posted by rocky

Thanks for posting back up. Try thumbing through this rather large thread to see if Edog did what you are looking for. Its one of the best out there.

Vizualogic / NAV A/V Switch / DVD Changer Installation Instructions

That's one heck of a write-up! Very thorough... I read all ten pages and looked at most of the photos. Unfortunately, the wiring in question (the plug between the NAV computer and the Head Unit) is simply "passed through" the plug-n-play wiring harness he used for his aftermarket setup. The company that made it doesn't even know what those wires do, they just tapped into the video, power, and control signals that they needed and left the audio & muting signals alone.

I will continue to search and call around to find out what the deal is... if anyone has any answers, they would be most appreciated.

Best,

[volvofan]

Okay, some more digging and searching (armed with the capability to change hondapilot.org to piloteers.org and get links to work) yielded some useful wiring diagrams and other tidbits of info:


Replace Factory Audio on Pilot EX-l/Navi

This one links to some wiring diagrams and also references the fact that the voice signal coming from the NAVI unit to the head unit is NOT amplified, which is good news from my perspective. That is verified in several other threads as well.


Navi Wiring Diagram?

This one has many useful audio wiring diagrams in one thread... I think they are for the '03 but I'm pretty sure the '03 and '04 are identical. This also clears up which audio is + and which is -.


EX-L NAV -> RES Retrofit - Possible??

This thread had the most POTENTIALLY useful information as it was directly discussing using the pins labeled as "unused" to get voice input through the stock RES headunit. However, whether or not this was possible hadn't been confirmed. It also gives the part numbers for three different head units used depending on whether the EX-L comes with NAVI, RES, or neither.




So...........

I now know that if the RES headunit will accept voice input I know which pins to put that unamplified input into. I still don't know what type of muting signal the head unit wants to receive in order to mute... the fact that grounding that pin did NOT mute the unit is frankly a little disconcerting... hopefully not a bad sign. Unless I hear some progress on the final linked thread above that definitively confirms or denies whether or not it's possible to use the NAVI voice inputs on the RES head unit, I think I will have to purchase a NAVI head unit to do a little troubleshooting by comparison. As always, any input or advice would be much appreciated.

Thanks,
-Jon

[volvofan]

Well, I tried hooking everything up last weekend to the "unused" pins on the RES head unit. Neither a ground nor a +12V input to the head unit caused the stereo to mute, and no sound came through the line-in at any point. The only thing I did NOT do was test this method on a NAVI or regular EX-L head unit to see if it DID work on one of them.

Opening up the RES head unit to see where those pins lead to did not give me any resolution... I traced them through the circuit board for a while but didn't see any simple solutions like dip switches or anything like that. The other option I'd hoped for (tapping the audio output from the GPS into the wife's Parrot CK3100 hands-free car kit right before the 7W amplifier) met with a similar fate, especially since it's a multi-layered circuit board so I could not trace the audio output back into the amp effectively.

All is not lost, however... we have successfully circumvented the crappy audio and the lack of easy-access volume control on the GPS by adding another pair of speakers. It doesn't auto-mute the stereo, but given the fact that it cost only about $10 and a couple hours of my time, and the fact that the wife likes it just dandy, I am going to call it a day with this project. I used a sound bar designed for Dell monitors. In fact, I ordered three, since I have a Dell monitor at home and another at work, so this gave me the opportunity to declutter two desks while saving on shipping. The sound quality is EXCELLENT compared to the tinny internal speaker built into the GPS unit, and the installation is very clean if I do say so myself. I actually mounted the sound bar upside down so that the volume control knob would be on the driver's side. I could have reached it if it was right side up, but my wife is 5'1" with self-described "T-Rex arms" I drilled two holes in the bottom (now the top) of the bar and inserted 1/4" threaded rod that I epoxied in place. It stuck up about 3/4" out of the sound bar. Poked two holes in the headliner and attached nuts/washers on the back side. Works like a champ. Hopefully this thread can help others even though it's not a perfect solution.

Best,
-Jon