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!
The photo is weird because it looks double- (or more) exposed. Given that z9 pin 6 and z10 pin 4 both connect to ground (L52 pin 2), I guess I wouldn't be surprised if they did just make that happen inside the spiral cable. Have you checked for continuity between those pins? I think the upper- and lower-caseness of Toyota's connector names matters. There could also be an upper-case Z9 hanging out somewhere.
All the popular smartphones are doing some pretty clever tricks with lengthened exposures and automatic compositing of multiple exposures without telling the user what's going on. Makes for interesting, and often good-looking results but there are some weird artifacts too.
L52 pin 11 is blank! Should be an easy mod! L52 pin 7 is also blank… Interestingly, this is the green wire on the chart saying “R/N”. Apparently R/N means relay. But said wire is missing. L52 pin 2 wire is white and black striped, just like the chart. L52 pin 1 wire is red, just like the chart. All other pins are full. Also I can confirm a 2010 spiral cable works perfect on my 2012. The plug that connects from the cruise control lever itself to the spiral cable only has two wires, red and black. I’ll be diving deeper!
Always a bit of a game to guess what Toyota means by their mnemonics, but I can't see any reason to guess this one would mean "relay". It serves a "mode" contact in the cruise control stalk. In my 2010 I don't have that; my cruise control stalk only has the on-off (button on the end), +res (push stalk upward), -set (push stalk downward), and cancel (pull stalk toward me) contacts. But in the owners' manual a couple pages later, it shows that in cars with radar cruise, there's a different cruise control stalk that has one more contact: you can push the stalk away from you to change the mode (dynamic radar cruise or normal cruise). That suggests the R/N mnemonic could mean "range / normal" or something like that.
After my last comment, I was totally thinking the cruise control lever might be different. Thank you for verifying! Now this is all looking quite impossible...
