Dear Wizards of PriusChat… I have an idea… First off, we discovered, if you have a Prius without the voice control button or telephone buttons, you can swap your old circuit board with one with those buttons… and those features will automatically work with an android headunit! Easy & Awesome! Now, my plan is… to add the missing buttons, to the right side of the steering wheel! I imagine, this won’t automatically give me Lane Keep Assist & Radar Cruise… lol… so the idea is to wire these buttons for aftermarket additional features. But the question is… where do these button wires go, after the clockspring? There are 2 missing wire pins in the plug going into the clockspring, I assume for the 2 missing buttons… Also, I’ve seen 3 !! buttons on some V wagons! But maybe the circuit board is too different… Can’t find any info on this… any advice is greatly appreciated! Thank you Prius family!
You can access the electronic wiring diagram with an inexpensive subscription to the tech info library, with details on this link.
They pull pin 4 of connector z9 (on the steering wheel side of the spiral cable) to ground: the distance button directly, the lane button through a resistance. That comes out as pin 11 of L52 on the column side of the spiral cable. A red wire from there goes to pin 64 of junction connector 3B, emerges again from pin 52, still red, runs to pin 11 of junction 4A, emerges again from pin 79 of 4B, still red, and goes to pin 6 of L60 at the driving support ECU. That is one weird photo.
Confirmed, ChapmanF has done it again! Z9 pin 4 is indeed blank on mine… If L52 pin 11 is blank… maybe this will be easy… Maybe… This is for the Distance button. The LKA Z9 pin 6 is also blank… But it looks like it connects to the cruise control within the spiral cable? So that’s impossible? Maybe I’m misreading this… And yes my Prius is far from normal. Usually I’m on the Facebook forums answering 101 questions. PriusChat is for the pioneers!