2012 sti and MVH-1400NEX RR shuts of quickly (10 seconds)

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stirobot
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2012 sti and MVH-1400NEX RR shuts of quickly (10 seconds)

Post by stirobot »

I've done several installs on several cars but never an RR. Generally familiar with electronics, computers, embedded systems, etc.

Quick symptoms:
-RR will start up and run for about 10 seconds and then shut off - headunit reports that it is connecting and such but then says "feature unavailable due to RR disconnecting" - RR does green light then two sets of flashing red light then nothing.
-I can make this behavior repeat by unplugging the power plug on the RR and plugging it back in
-I know the RR is partially working - if I unplug the power and plug it back in with the OBDII part out the headunit tells me to turn on the ignition

Full setup:
-2012 sti that came with bluetooth but no factory nav (20 pin connector and 3 phone buttons on wheel).
-Replacing an aftermarket stereo with a better one
-Maestro RR is 2016 build ADS-MRR (RR(512) 3.0) and flashes just fine using the desktop version of the flashing software
-I am only using several wires from the car on the harness - these are SWC1/SWC2 (wired that go to SWC1/SWC1 on the RR harness), SWC common ground (goes to common ground), 2 OBD II wires plugged into the harness, 3 power wires to the RR (checked and yellow and red get 12v+ at appropriate times). All of the other wires (illum, sub remote, reverse, ebrake, etc) are direct to the headunit (I don't think any others are required to keep the RR running - this could be where I am wrong)
-The data wire is plugged in from the RR to the headunit

Things I've tried:
-Checking settings on headunit (it doesn't really let you touch the RR settings unless it is working)
-Checked power to the RR - used multimeter and it all looks good to go
-Checked powering on with just the SWC wires connected (OBD II wires not connected) - does same quick shut down thing but gives ignition error
-Followed the reset procedure on the RR (hold down button on RR while plugging in) - this produces the blinking lights per the instructions

What's left to check:
-Check ground on 3 wire power harness to RR -checked
-Move SWC Common ground to pin on RR?-haven't checked
-Reflash RR - maybe I got something wrong like the serial number of the headunit - checked by flashing a known bad serial number and there was not communication between the devices at all

I will admit that I am using a hacked up harness. I was sold the wrong SU2 harness, but checked all wiring diagrams and based on the simple SWC's to SWC's and OBD II (CAN 1) to CAN 1 connections I'm doing this should work.

Chris LaRoche
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Re: 2012 sti and MVH-1400NEX RR shuts of quickly (10 seconds)

Post by Chris LaRoche »

This application requires the SU1 t harness. I would start there, see if your problems persist.
Chris LaRoche
Automotive Data Solutions
Technical Support - Maestro
MECP Master Installer

stirobot
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Joined: Sat Apr 18, 2020 12:59 pm

Re: 2012 sti and MVH-1400NEX RR shuts of quickly (10 seconds)

Post by stirobot »

I understand. I was merely trying to save $30 on something I probably don't need by getting a hint about where to start looking. I figure it's only a wire or two that is required to connect that is missing.

stirobot
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Joined: Sat Apr 18, 2020 12:59 pm

Re: 2012 sti and MVH-1400NEX RR shuts of quickly (10 seconds)

Post by stirobot »

I’m happy to say that the SU1 harness did the trick. I’d love to know why but eh. It works. TPMs even works!

My subwoofer doesn’t work (it did before) so I’ll have to track that down. Probably a misplaced wire or something.

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Dara DeGrand
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Re: 2012 sti and MVH-1400NEX RR shuts of quickly (10 seconds)

Post by Dara DeGrand »

There is a lot more going on in the harness than you think- that's why it's required. Glad it's working for you now. Enjoy!
Dara DeGrand
Maestro Technical Support Manager
Automotive Data Solutions Inc.
8400 Bougainville, QC
T 514.807.2888
TF 866.427.2999

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