I went to look a 2002 SC 430. The owner had a new head unit installed. The result was, not surprising to anyone here, that the Sat Nav did not work and steering wheel controls did not work. After the test drive, I told him that if the Sat Nav and the steering wheel controls worked, I would buy the car at his asking price. He said that he would make that happen. His car stereo shop spent days. They tried 4 different head units. They ended up with a Pioneer model DMH 241 EX that they were able to get all the steering wheel controls to work, the Sat Nav would now open up and come on, but without the Sat Nav function or the tilt function. The car information screen came up and worked. I bought it anyway. He spent $500 on the radio fix attempt. The tires are brand new, non-RF. He had a set of coil over adjustable shocks installed just before listing it.


In my searching for a radio/Sat Nav fix, I came across a forum posting from about 12 years ago that said they used the main circuit board out of the OEM radio in conjunction with their new head unit and everything worked. But, there was little information about that install.


So, my question is, does anyone have any information on that type of an install ?


I have not opened up the dash yet to see in what state the stereo installer left the wiring harness. I am hoping that I can still put the OEM head unit back in, but am intrigued by the OEM circuit board method.

Please don't tell me about beatsonic.

Thanks,
Greg

 

I removed the new radio. Holy crap what a rats nest of wires back in there. I found a parrot.
I found the original plugs stuffed back in there and plugged in the OEM radio and the AVAC control.
Everything works except the tilt function for the sat nav screen. I will look up what that problem could be and how to fix it.

 

So, the tilt motor is dead. I will try to access it and remove it tomorrow.
BUT. It just occurred to me that all 3 of plug in connectors for the OEM radio were just sitting there unused by the new radio install. So, if I remove the circuit board and plug it into those connectors and then plug in the new radio using the completely different connectors for it, the new radio should work and the sat nav should work. We'll see....

 

NOPE. Didn't.

 

I am not saying that it can't be made to work, but at 2am I just gave up and installed the OEM radio.

There are 3 plugs in the back of the OEM unit. One of those plugs is used by the new unit via a Lexus/Toyota adaptor black box. A harness comes out of the black box with a female socket on the end of it. One of the plugs for the OEM unit ( the larger one that plugs into the right most socket on the OEM unit looking from the front ) plugs into the female socket. So it might be possible to create a split on the OEM's socket wiring harness so it can be plugged into the both the OEM's circuit board and new unit at the same time. I don't know what, if any, conflicts (smoke, fire, popping noises) would arise from doing this.

For right now, I am just going to give it a rest. At least unit after the trip to see the eclipse.

 

Watching this with GREAT interest!! I bought my car with a pioneer head unit already installed, pioneer works great although the nav unit and controls on top of the climate control seem dead! Steering wheel controls do work though. BUT I want at least to have the nav door open and close with the button! I am not a car electronics guy and am half afraid to tear into it for fear of screwing something up! I do have the stock radio in a box in the garage if I need it for something.

 

If your climate controls for the sat nav are completely dead, check to see if the pioneer install did not use the OEM double DIN cage to mount the pioneer. Do you still have the door that closes over the radio ? If not, then that may be you problem. The power for the sat nav door some how comes through the mounting cage and door operation system for the radio. When they first installed the pioneer in my car, that was the problem. After they used the OEM cage, the sat nav door would work and it would power on, but no sat nav system.

I think that I am just going to do this: Install a Garmin in place of the OEM sat nav. It makes the most sense. I would then have a modern, updateable, sat nav system. With the pioneer install my OEM sat nav door would work and the unit would power on, it just would not access the sat nav system. I would lose access to the car maintenance screen, but I log and track all maintenance and fueling on a spreadsheet. I now have to find the correct replacement motor for the tilt function. I will update when I do that.

 

In case you were wondering, the OEM radio is a Pioneer

 

Yah, right, I forgot that. Ok, if I refer to the aftermarket pioneer as the nouveau pioneer will that help differentiate it from the OEM pioneer ?

 

Yes, I still have the door over my radio and it works just fine. And I dont really care about the nav unit I just want the door there to work. Was thinking about a small glovebox behind there for sunglasses and such. Your Garmin idea does sound interesting however.

 

Or just new head unit...

 

The title of the thread "How do you install a new radio using the OEM radio's circuit board so Sat Nav works ?" Should be: "If you are getting a modern head unit why wouldn't you also get a modern GPS ? " So here we go.

Top to bottom the cage, frame, Garmin 65, trim

The garmin mounted in the frame using the garmin mount. At this point it is easy to release the garmin from it's mount, there is access to the release clip on the back of the frame.


Assembled. I am now waiting for the replacement tilt motor to arrive so I can put the unit back together and in the car. I will install the power socket while I am waiting.
Please note: When installing the power socket for the Garmin power adapter to plug into, locate the socket up at the sat nav location so the entire Garmin power cord is up high under the dash and not running down to a socket located below the radio in the center console area. The power cord is the antenna for the Garmin, so you want it up high for best reception. Others that have installed a Garmin have reported that it takes up to 10 minutes for it to find satellites. My install finds them in seconds.


When I have parts left over at the end of a project it usually concerns me....

 

First photo is the rat's nest that an automotive stereo shop called an install. The head unit had random problems. Steering wheel controls sometimes worked. Back-up camera stopped working. The windshield antenna was not hooked up and rear antenna was replaced with a rubber stubby, but they left the antenna motor plugged in so it ran, noisily, every cycle. The rear camera sensor wire as broken out of the plug. The power to the Axxess steering wheel control adapter was hooked up to power on all the time. It is supposed to hooked up to switched power on ignition. They used crimp connectors and left a bunch of wires just loose. They did not initialized the amplifier before they removed the OEM unit. You have to use the OEM unit to zero out the bass, treb. balance, fad, etc. before installing the new head unit so it is starting at a zero baseline when it makes adjustments.




I soldered all the connections and shrink tubed. So I now have kind of a harness that I can just plug into the car and the new head unit. Everything with the head unit now works.


The new Garmin is installed in the gutted cage for the OEM sat nav. I really like it. But, the door and tilt do not work. I have a feeling that those two operations require that the original sat nav unit has to be in the loop. Before, with the new head unit installed and the OEM sat nav installed, the door would operate with the buttons, the tilt didn't work because the motor was bad. I will experiment a bit with the OEM circuit boards for the sat nav. If that doesn't work, I can convert it to manual operation or, with a couple of DPDT switches and a mico switch to sense when the screen is tilted fully in, I can make the motors do the heavy lifting for me....

 

I got the door to work by plugging in the first circuit board of the OEM sat nav unit. The one with the plug sockets. Just dangling out of dash. There might be room to install it back in it's original position in the cage. I will work on that. But, the tilt still does not work with the button. It does work when I power it directly, unplugged from it's control circuit board. I will swap out that board, but the replacement I have looks worse.

 

Are you talking about the circuit board in the post above? And where did that circuit board come from? Man I want to do this but I'm afraid nothing will work when I'm done! All works now except the nav and nav door!