Steering wheel harness for Android head unit

Tiny
XANDY
  • MEMBER
  • 2012 TOYOTA RAV4
  • 2.4L
  • 4 CYL
  • 4WD
  • AUTOMATIC
  • 75,000 MILES
Hi! I am trying to replace my original stereo head unit on my vehicle listed above with an 7" Android head unit. The steering wheel control harness on the new one is small for the stock, it only have a 20-pin while my vehicle has 28-pin. I was looking all over Google if there could be some store that are selling a conversion jumper for this, but I am not able to find one. My second option is to just do a manual hard wiring. Now my problem comes with where in the 28-pin can I locate the ones for the steering wheel control, if you could please help me with the schematic diagram. I would highly appreciate it. I have included some pictures for your reference. Thank you so much!
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Tuesday, February 6th, 2018 AT 1:47 PM

7 Replies

Tiny
STEVE W.
  • MECHANIC
  • 14,524 POSTS
I highly doubt that you will be able to use any of the factory controls with the replacement stereo. The factory controls use the CAN network to control the OEM system while the replacement uses direct switching. That is why there is no adapter, because the two systems are not compatible. The unit you unplugged in the dash is not the actual stereo either. It is a display and control head only. The actual stereo system has three to five modules and is also connected to the instrument panel, the body control module and the traction control systems. That is why the various plugs you removed have so many connections. Anything that you control or view through the OEM head unit will be gone with the new stereo and you may have other issues depending on how the security system and options like remote start, key-less entry and such are connected into the system.

FYI there is no universal wiring color system for vehicles, so attempting to wire it in using blue to blue, red to red, brown to brown etc, will result in a lot of damage to the vehicle and the stereo. The attached wiring is for the basic system.
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Wednesday, February 7th, 2018 AT 10:02 AM
Tiny
XANDY
  • MEMBER
  • 4 POSTS
HI! I got the steering wheel control to work. Had to get diagram from the dealer and got the wiring to work. Thanks anyways!
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Thursday, March 15th, 2018 AT 8:23 PM
Tiny
STEVE W.
  • MECHANIC
  • 14,524 POSTS
Did you wire direct or find an adapter?
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Friday, March 16th, 2018 AT 9:15 AM
Tiny
XANDY
  • MEMBER
  • 4 POSTS
Wired it directly, sort of customized jumping harness. Its not easy though, and will not recommend it, unless they know what they are doing. Took me a lot of research on the wiring schematics of the Rav4 steering wheel control and got one from the dealer, Also I was fortunate to find an electrical auto parts seller that customize harness', so I did not need to splice on the stock wire.
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Friday, March 16th, 2018 AT 1:28 PM
Tiny
STEVE W.
  • MECHANIC
  • 14,524 POSTS
Sort of what I expected, a cut & paste harness to connect the wheel switches. Those can be "fun" to do. I've done a lot of custom harness work like that over the years, but doing it myself and telling someone the process is a lot different. Especially with the newer vehicles, cutting into or splicing the wrong wire could do serious damage. One of the hard things on this site is judging the actual skill levels of the person asking the questions.
So I tend to "discourage" the questioner, just to prevent the "Well you told me to cut the blue wire and now the ECM is burnt up" replies.
Sorry if it made you think this site was a waste of time. Please return if you need other assistance.
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Friday, March 16th, 2018 AT 2:11 PM
Tiny
XANDY
  • MEMBER
  • 4 POSTS
Yup! We'll do! Good thing my steering wheel control was analog, that made a whole lot of difference. Thanks again!
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Thursday, March 22nd, 2018 AT 8:09 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 51,648 POSTS
STEVE W. Is one of your best!

Use 2CarPros anytime, we are here to help. Please tell a friend.

Cheers, Ken
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Monday, March 26th, 2018 AT 11:00 AM

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