headunit faceplate extension woes continued..

**mattress** · 10-04-2005, 03:42 PM

in a previous thread I posted how I'm trying my hardest to relocate my headunit to the glovebox, and mount the faceplate in the headliner..
Pioneer 7700 -
http://www.pioneerelectronics.com/pn...874695,00.html

it's got a 12 pin connector that connects the face to the unit.

I started out by using 2 pieces of cat5 cable. that didn't work at all.

next, I tried using a 10 foot printer cable (the old kind.. LPT/parallel/whatever you wanna call it) I chopped the connectors off, and used 12 wires. I matched them up with a multimeter to make sure I had the same wires on each end.

I hooked it up in my car. the faceplate turned on for a second, and turned off for a second, turned on for a second, turned off for a second, turned on, turned off ... and nothing.

I brought it back inside, checked all my connections, etc... everything seemed fine, and I couldn't find a problem.... I work at circuit city, and the boys in the roadshop were kind enough to take a look at it for me. they actually took the hu apart and soldered straight to the circuit board (where I was soldering to the pins).
they couldn't get it to work at all.

I tried going to a custom car stereo shop, and they wanted to charge me $100 for doing JUST the cable between the HU and face... so that was BS..

Next, we have a set of 6 channel RCA cables were going to try out... (12 wires total) ... other than that, I don't know what to try... I'm kind of stumped. Maybe my complex display on the HU can't handle the extension?

help me out guys... (and before you ask, yes I'm pushing the pressure switch in! haha..)

**mushin** · 10-04-2005, 04:28 PM

Just how long are you trying to make this thing? At 10ft, you could plausibly be running into 1) signal bounce 2) noise 3) too much voltage drop 4) Venusian mind control rays. Depending on what the source of the problem is, throwing higher quality cabling at it may make no difference.

You might try a very short extension (< 1 foot). If that doesn't work, it's more likely your problems are elsewhere (some security function you missed, who knows?)

Oh, and it still works normally, right? You didn't accidentally bust something?

**mattress** · 10-04-2005, 11:32 PM

Originally Posted by mushin

Oh, and it still works normally, right? You didn't accidentally bust something?

everything still works fine. They even let me swap it out for a new one ... so now I could even start from scratch if I wanted to try it again...

next time I get some time to throw at this project, I'll try making a shorter extension like you suggested ... it's just really discouraging when I've put SOOO much work into it ... so much time and effort, and i still don't get any results

**kmcniece** · 10-05-2005, 12:39 AM

My understanding, after talking to the guys at the radio shop.....

The increased distance creates too much resistance between the faceplate and the deck. Therefore, the faceplate, which already runs fairly low on the voltage side, doesn't get enough "juice" to function properly......

In my opinion, that sucks..... I wanted to mount my faceplate in the cubby and put the cdrom behind it....

If you do figure this out, let us all know.....

**mattress** · 10-05-2005, 02:59 PM

Originally Posted by kmcniece

My understanding, after talking to the guys at the radio shop.....

The increased distance creates too much resistance between the faceplate and the deck.

thanks for the reply. This is what my guess would be too... a guy in our roadshop has some old 6-channel Monster Cable RCA's he said he would let me use ... since we don't see monster cable for car stuff anymore.. If I had to guess, RCA cables would provide the smallest amount of resistance out of anything... I don't know if I want to give it another shot though, it's so time consuming, and so much work...

**Bugbyte** · 10-05-2005, 03:14 PM

One way to check that would be to measure the voltage at the HU and at the other end of the cable. It ought to be similar.

If it really is just a power supply problem, couldn't you add a linear regulator like one of those Radio Shock LM317T's near the faceplate or even as the sole source of power to the faceplate?

**mattress** · 10-05-2005, 11:17 PM

Originally Posted by Bugbyte

One way to check that would be to measure the voltage at the HU and at the other end of the cable. It ought to be similar.

If it really is just a power supply problem, couldn't you add a linear regulator like one of those Radio Shock LM317T's near the faceplate or even as the sole source of power to the faceplate?

whoa, you're asking the wrong guy lol.. I don't know much about electronics and such.. so i'm not really sure what kind of difference a voltage regulator would make ... let alone which pin to use it on (there's 12 pins..) and I haven't tested the voltage at each pin either. also, I think one of the pins is like a control pin, telling it when the face is open or close.. not too sure though, and pioneer isn't to keen on giving out information like that :-\

**Enak** · 10-06-2005, 05:54 AM

Your best bet is CAT5... but instead of just connecting up pin to wire you need to do it sensibly.

1. Make sure you are not going to much distance... build it with a short cable first off.
2. Find the ground (0v) on you head unit.
3. Connect this to one wire in every pair of your CAT5 cable. So with twelve connections you'll need 3 cables (12 pairs).
4. Connect each pin at both ends to the other wire in each pair.
5. Find ground on the face plate and make your final connections.
6. Make sure you know how the head unit knows when the face plate is down and trick it into thinking otherwise.

Should work fine this way.

**mattress** · 10-13-2005, 07:15 PM

bringing back an old thread...

I tried with printer cable, and the display turned on and off for a second 3x each, and stayed off after that. The guys at the circuit city roadshop ran into the same problem, so I'm guessing it is a low voltage/resistance issue.

one of the members suggested adding voltage regulators to the ensemble. How would I go about doing that?
Would I need a regulator for each pin?
How would I pick a regulator?
use a volt meter and check the voltage at the HU, and buy the regulator that has the same value?

anyone have any more suggestions? I've asked some other local custom car stereo shops ... one guy wanted $100, and another guy wanted $200... that's pretty insane..

**Sleeka** · 10-13-2005, 11:31 PM

I had my faceplate remotely mounted using Cat5 cable. I didn't have any issues except for not being careful with my soldering and blowing it up (ended up being not that bad of repair cost). The head unit is a Pioneer DEX-P99. I have since put it back to stock and it still works great. The Cat5 jumper was about 20" long.