Buster06

Many thanks to oneround and khuong for a quick reply.

I’ve been using the GROM aux input with my iPhone. Lately, my Nav screen starts flickering and display lines of different colors, so I think it’s time to replace it.
I plan to get the android head unit with CarPlay capability, retain the stock radio. Audio will be RCAed to the GROM unit.

I’m sure I will re-read this thread and few others many times over.

oneround

@Buster06 You've probably already seen it, but when I was trying to decide what to do and if you're keeping the ML radio and amp, I found the most help in this thread from @Seattle SCone

oneround

@khuong Starting the change from Axxess ASWC-Toy-Lex to PAC SWI-RC-1. Hopefully I will implement your schematic and the push-button operation of my my nav door will work again.

On my 2002 the steering wheel does not need to be removed to get the under cover off the base of the steering wheel. I found this out as I had the wheel turned to left when pulling it into garage and that exposed Philips screw on right side of wheel. Turned wheel to right and the left side screw was exposed. Looked underneath and there is only one screw through the undercover.

I still disconnected the battery. Don't want to mess with the blue wire while system is hot -- especially with the airbag still on the wheel. I won't get to finish the job today - wife's birthday (she's sleeping in). But at least I can get the tap into the LAN wire required by PAC hooked up and ready for next phase.

khuong

That's a nifty trick @oneround -- I had to take mine off anyways lol -- I had to tap the clockspring for wire to enable resistors on all the buttons for my steering wheel.

And yes I always disconnect the battery! For most work lol.

oneround

@khuong I've been looking back through the thread for the new method you used to get the nav door working (using resistor and connectors from an Axxess box). I just realized the radio unit in my car has 3 connectors on the back. I looked on the unit label and Pioneer has a manufactured date of November 2003. Since the label on the car itself is April 2001, I'm guessing the unit was replaced with something made for a 2004. There is nothing in the records the PO kept about this. Has me wondering what other surprises I might find down the road. I wonder if this contributed to an early demise of other components in the chain. Not on the hardware side, but on the part of whomever made the swap. Interesting that the wiring diagrams for the 2002 model year show 3 connectors, so now I'm wondering what year unit in the pic you posted is from.

And the real reason I'm posting:
Did you use the blue shrink wrap to cover deleting whatever Axxess has under their shrink? Asked as I'm getting ready to pull the Axxess box and go with the PAC unit.

oneround

Posting to confirm the method and the patch cable @khuong posted above (see post 39 for the patch cable) works for the 2002 model year. Many thanks.

khuong

Sorry for the late response! I think you got it figured out.. but the 3rd connector which is blue on my car was for Telephone features for the SWC/ECU.

I actually just deleted the ASWC module because it was causing my tons of headaches, and their support was extremely unhelpful. Any wires that were cut/spliced, I taped up or heatshrinked around so there would be no risk of shorts or anything considering I have so many things stuffed in that area...

oneround

@khuong Thinking of doing some more following in your footsteps (resistor mod). I have some questions - hope you don't mind helping out an electronics dummy.

Is there space in the switch case for the resistors? Did you use a small board, or just make jumper wires from the solder points?

oneround

For anyone thinking of doing the resistor mod, I've got a bit of info (and plan to update as I find more). Also, if in reading you see a mistake, PLEASE point it out.

First, the Club Lexus link provided by khuong above is working, and the attachment in post #1, "Steering Wheel Radio Controls Hacking.pdf" shows solder points for attaching resistors. I have taken my steering wheel pod off and I can confirm the points in the GS post also applies to the 2002 SC430 I own. Note: I do not have the cellphone option in my car. If you do and you use it, I can't comment on how to proceed as I can't test.

The OP @rgarjr in the GS section never had steering wheels controls, so he ran two wires (all that's needed for a resistor network in this case) into the wheel and found places to attach them in the spiral cable. In my case I have the OEM steering wheel control. It has five wires that attach from the steering wheel radio control pod and enter the steering wheel under the airbag. I still need to run down if any wires need to be preserved for this mod, and I need to find/confirm the telephone wire the GS post mentions.

For the SC430, I believe that telephone wire is the color blue on the C10 connector -- found under the plastic shroud under and behind the steering wheel. C10 is one of the connectors on the output side of the spiral cable. At least that's the wire the FSM shows going off to the telephone computer (it's labeled TLSW on the diagram). I worried that the notation TLSW might mean Telescopic Steering Wheel, but that function is found on the next connector over, C11. But I'm reassured since the PAC Audio SWI-RC-1 uses that blue wire but the only function they perform is volume up/down. I have inferred that this wire is communicating telephone volume up/down if I had the telephone option, and PAC has simply co-opted it for radio volume control. However, the wire color leaving the pod is not the same as leaving C10. I haven't yet pulled off the shroud to try and find a wire that has continuity from control pod to blue on C10. And while I'm at it, same for ground, which is brown on C10.

I think the OEM radio takes input from the control pod over the green wire on C10. That is the multiplex wire according to the FSM and would therefore find it's way to the radio via the Gateway ECU for the volume up/down functions.

Assuming I get this to work, the change will be relatively cheap and easy to implement as long as you can solder some small wires. Some time back I purchased a 1,000 count variety of resistors for around $5. Similarly I picked up some mini breadboard pieces recently for about the same price. That and a bit of small gauge wire (I'm using 24AWG) is all that's needed.

As noted above, the colors of the 5 wires going into the control pod do not match the 5 colors coming out of connector C10, so I may have to pull the steering wheel and do more investigating. If I do, that will set my timeline back a few days due to a household project that has priority.

oneround

Update #1: I checked for continuity between the blue wire (pin #1) on connector C10 and the blue wire going from the radio control pod on the side of the steering wheel. No go - Looks like I will have to pull the steering wheel.
Update #2: With the steering wheel pod out of the car, the horn no longer works. Put pod back in, horn works. The YouTube video on SC430 Spiral Cable replacement (1:28) shows 3 wires from the steering wheel pod heading into the spiral cable (yellow, green, black), and two (blue and white) going over to other functions (cruise control module and horn?). I grabbed a screen shot and will post it below. So, I'm not surprised the horn didn't work, or that I didn't get blue wire continuity in update #1 (never tried cruise control but guessing it wouldn't have worked either).
I "think":
The blue wire is coming from the cruise control and horn side (think horn control) and going into the pod, then getting mixed with audio and coming back out multiplexed on the green wire to the spiral cable. That use of green would be consistent with the colors coming out of the spiral cable.
The red wire into the spiral cable goes off to cruise control. This would also be consistent with the spiral cable output colors.
Guessing now:
The white from the pod bundle goes to the wheel to form a circuit (Blue and White) and maybe the ground side for the horn?
The while/black coming out of the cruise control side and going into the spiral cable is ground (its usual function in Lexus wiring) serving Cruise control?
If my guesses are correct. that leaves the yellow and black wires undefined. One of the wires has to be power for the LEDs on the pod (Yellow?).
Here's hoping the remaining one (black?) is the "unused" telephone wire in the GS post. This sort of requires the white first mentioned under Guesses to be ground for the horn and audio control buttons. I Suspect it might be the ground for the pod's LED power and I will have to try and source some pins to fit Lexus connectors. I will need them to populate the blank spaces in the input/output spiral cable connectors so I can get the resistor network values over to the radio. Once I find time to get the wheel off, I will confirm what colors have continuity on the other side of the spiral cable and firm up what I will have to do. Fortunately this is all cheap parts. Now if I could just get out of some household projects...




Any help seconding my guesses, and/or confirming would be greatly appreciated.

wsvc206

GmanSC

wsvc, looks nice.

JohnSenior

I just had a lot of fun reading this thread AND it confirmed form me that an overhaul project like this is well beyond my capabilities. I live in the Dallas area and would love to find a professional shop I can trust to swap out my radio for the latest Apple CarPlay unit and install a back-up camera that displays from the current NAV screen. Any suggestions for someone I can trust?

maxrpm

Check out SC430Mods.com for DIY alternative.

oneround

I still haven't finished my audio makeover yet. But I did find one bit of information for early SC430s (at least true for my 2002), and that has to do with the usefulness of add-on "boxes" when replacing the OEM radio unit. Namely the ASWC-Toy-Lex and the PAC SWI-RC-1.

In my case, with an Android head unit, all I could get was just volume up and down. The ASWC unit precludes use of the Nav door, so I got rid of that option pretty fast (although I believe it works the door in later model years). The PAC unit has the car owner tapping in a blue wire that exits under the steering wheel (specifically in the C10 connector).

So, if all one can get from these devices is volume up/down, there is no need for either device. Just tap the SW1 (key 1) wire from the Android head unit into the same blue wire used by the PAC system. Does the same thing - controls volume up down and no need to spend money.

I even cut the blue wire and no other systems on the car were impacted. Near as I can tell from the wiring diagram, the blue wire feeds volume up/down info into the telephone computer and nowhere else (well probably to the OEM radio to, but that's gone already for this thread). I sure don't have one of the ancient phones, so...

I have made a small circuit board with six resistors that I will be attempting to hook into the car much like the GS mod done on this board (see my post referencing it below). But it might be weeks away, lots of stuff happening at the household. I will post final results once I get this accomplished.