Wiring diagram help needed

[kb426]

I bought a 2013 chevy sonic gauge cluster to try and use for future projects. I can't seem to find a wiring diagram for it. Does anybody have access to something that could label the 9 wires feeding into it? Thank you.

[enjenjo]

As I understand it, that gauge cluster has stepper motors to move the needles, and requires a computer interface to make them work. I understand it can be done with a Raspberry Pi, but have no idea how it's done.

[kb426]

I wondered about this. The sonic is canbus also. I haven't gotten educated much about that. I went to ebay to buy a wiring manual and found $300 ones. I paid $18 for the cluster so if I can't make it work, it's not a large loss.

[enjenjo]

I would suggest calling Classic instruments. If any one has figured it out it will be them.



I have a couple ideas about figuring out which wire is which. But my question are they switching the ground or the power?

[kb426]

I researched the Raspberry Pi a little bit. They sell modules to drive stepper motors as well as many other things. I'm intrigued somewhat. I think I'll call Classic. They can surely tell me if this is a really bad idea. Thank you.

[wayne petty]

Pin 16 is ground..

pin 31 is switched ignition positive power  10 A fused.

Pin 32 is battery /memory power.. 10 A fused

Pin 26 is bidirectional data stream.. i don't know if that is low or high..

Pin 25 turns on the check engine light LED.  i can't tell if this is a pull to ground.. probably..

-----

Pin 11 is the ground side of the ambient air temp sensor.

Pin 12 is the current limited side of the ambient air temp sensor..  works like a ECT sensor.

-----

Pin 9 is the Ground for the set and Menu buttons circuits.

Pin 10 is the Set buttons... with resistors .   604 Ohms, 1020 Ohm,  1910 Ohms, 5360 Ohms.

Pin 11 is a switch for the menu button..

this is not much. and it won't get more than a wake up signal from the cluster.

[kb426]

I had some time today so I connected power to the unit. It does power up and you can hear the stepper motor cycle. I went looking for an analog to canbus converter. Everything is the other direction. I have one of those OBDII bluetooth adapters that I can use with the Android app, Torque. That is the same direction that should be used to power the gauge cluster. I'll keep my eyes open for an easy fix. Maybe in the summers travels I'll find an adapter that isn't $500. Thank you for all who contributed to this.

[wayne petty]

the trouble is its going to take a specialized computer to ping the devices.. to see who is there and their address on the system..

with that you could probably write a program to control them.   it would take a significant effort.  its not impossible.

it might be easier .. still crazy complex.. to scrounge a proper PCM and BCM if needed with the car harness.  build up substitute sensor signals..  so the pcm thinks it hooked up properly to the motor.. but having a specialized computer recording the canbus packets when you move one sensor to effect a change. so you could identify the info needed.

this is NOT impossible..  there are companies out there using OBD2 ford computers wired in like a break out box to allow a full display of sensor values on EECIV cars..  where you could only do codes on these 84 to 95 fords..

one can use the proper GM computer hooked up to various sensors to control that dash. even without any electronic fuel controls.. the hardest part would be tachometer/rpm.  the GM computers are not looking for a sine wave.. they are counting tone wheel slots.. and they are not even all the way around .. it might have 20 poles then a gap.. then 3 poles and a gap.. and then back to 20 ..

you have to understand.. i am good at reverse engineering.. but this is beyond anything i would want to dive into PERSONALLY..

could there be a way to bypass the programmed chip and operate the individual stepper motors and lighting? probably.

i feel bad that i might have started this by mentioning the cute dashboard design on these..  i did not have access to wiring diagrams for them at that time. for some reason the older i get.. the smarter i get.  sometimes too smart..


wayne..

[kb426]

You're not guilty, Wayne. I had a Sonic for a rental car at the LA roadster show a few years ago. That's what started this. Then I was able to buy one for $18 with shipping. Not much for an experiment.

[wayne petty]

you could always wire it up and hang it on the shop wall..  so you could have it light up as a display ..

some day in the future.. it might be much easier.  or not.


The Hindsight Optical future store has not opened yet.  well.. i am wrong on that also

https://heinsighteyecare.com/