oem camera on aftermarket hu issues

Ok I'm now baffled by what is going on with my truck! I have the new Pioneer AVH-P4400BH on my 09 Tacoma. It has the reverse camera and the reverse camera mirror also. I took apart my old Nintendo64 AV plug because it has the shielded AV cable with pins already installed so it was pretty easy to tap in. I hooked my reverse sense wire to the red wire in the kick panel that supposedly powers the reverse lights, and I hooked the center wire of the AV cable to the red wire and shield wire to the black wire on the camera harness plug behind the flip-down compartment to the left of the steering wheel... The head-unit switches to the camera when I shift into reverse, and I get a good picture, but when I shift out of reverse, the head unit goes to the radio screen for a few seconds, and then will go back to the camera screen until I tap the screen to get it to go away. However, after a few seconds it will go back to the camera screen again. It keeps doing this over and over and over until I just turn the rear view camera off on the head unit. Anybody have any ideas why it's doing this?

Did you test your reverse signal wire? Is it showing voltage / ground any time other than when the truck is in reverse?Kenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

offroadzj wrote: Did you test your reverse signal wire? Is it showing voltage / ground any time other than when the truck is in reverse?

That's the weird thing...as long as the reverse camera setting was enabled on the head unit, it kept switching back to the camera even after I totally pulled the reverse trigger wire loose...so I don't know what's going on. I'm going to look at it some more today. But it wouldn't have anything to do with the parking brake relay always having it grounded would it?

It shouldn't. With the reverse signal wire disconnected, test the wire on the radio side (coming out of the radio) and see if you are getting any voltage on it... there could possibly be a short inside the h.u.Kenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

offroadzj wrote: It shouldn't. With the reverse signal wire disconnected, test the wire on the radio side (coming out of the radio) and see if you are getting any voltage on it... there could possibly be a short inside the h.u.

Yeah I tested the wire on the radio side and no voltage at all. But if I leave the head unit camera setting on, and turn the unit off and back on, it goes to the radio first, then after a few seconds it goes to the camera screen. And that's with the reverse trigger wire on the head unit totally disconnected. I'm about to call pioneer.

I had a similar problem once, but it was an Advent OTORAV1 OEM-lookalike navigation radio and the car was a 2011 RAV4. So there's a slight difference, but it still was a late-model Toyota. It took a lot of fooling around and troubleshooting, but what I found out was that the Advent unit has a completely secret, undocumented feature---it automatically senses video signal on the camera input and switches the head unit into "camera watching" mode, even if no signal is supplied to the reverse wire on the unit. This is why I hate aftermarket radios---the manufacturers always do weird stuff, and are too sloppy to ever document any of it. So anyway, what I found out is that when the RAV4 was placed into reverse, the OEM Toyota camera turns on (of course). But when the car is placed back in Drive or Park, the camera actually stays on for about 10 more seconds. The solution I came up with was to take a relay like this: 86: ground 85: reverse lights on car 87: video output from Toyota camera 87a: no connection 30: video input on aftermarket radio. You would think that running the video signal through the relay would do all kinds of crazy stuff---after all, now the cable is unshielded, and the signal is running through the relay where who knows what the relay coil could/might do to the signal. But surprisingly, it worked fine, made a nice clear picture, and no complaints from the customer about it. So anyway, I would try this with your Pioneer unit: 1. Disconnect the reverse wire entirely, and then see if the camera input still works. If it does, surprise! The unit has some kind of auto-sensing feature that the manufacturer felt you didn't need to know about. 2. If #1 checks out, with the car in reverse the whole time and the car on and the radio on, try unplugging and replugging the RCA cord going into the radio's camera input......does it work right? Do you see the image with the RCA plugged in, and does it revert to regular radio with the RCA unplugged? 3. If #1 and #2 both check out, wire in the relay and that should probably work. ONE MORE IDEA: I'm not familiar with that Pioneer unit you have, but see if you can make sense of the instructions.....see if there's the off chance that there's a setting you can change to turn off the automatic image sensing (if it even has that feature). That would save you the relay.

I finally got it working.  I had to call Pioneer and talk to their tech support and clear up some things that their manual didn't explain very well.  Changed one setting on the unit and all works perfectly now.

What setting was it?Kenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

offroadzj wrote: What setting was it?

On the home screen you can turn the rear-view on or off. I thought off would mean that it wouldn't work at all, but it just means that it only comes on in reverse.