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Need 9th gen wiring diagrams

1159 Views 19 Replies 4 Participants Last post by  Jack2000XD
So I have 9th gen parts like the gauge cluster, stereo and other small electronics that I’m trying to put in a 7th gen but can’t fig out how to power them up.
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More than likely, it will not work and is impossible to. BCM and PCM run those components and are not compatible with each other being 2 generations apart.
It's like trying to get a Windows 3.1 computer to run Windows 11.
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More than likely, it will not work and is impossible to. BCM and PCM run those components and are not compatible with each other being 2 generations apart.
It's like trying to get a Windows 3.1 computer to run Windows 11.
Maybe so but I want to try. I think it’s possible with a bit of wiring and engineering
Maybe so but I want to try. I think it’s possible with a bit of wiring and engineering
I'm with repairman but having read the previous posts the car can't be much more broken than it already is. I see no harm in trying! Wiring diagrams here for a modest price: Do It Yourself Automotive Repair Information | ALLDATA DIY

I have alldata and can confirm it has all the diagrams you might need. Good luck!
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I'm with repairman but having read the previous posts the car can't be much more broken than it already is. I see no harm in trying! Wiring diagrams here for a modest price: Do It Yourself Automotive Repair Information | ALLDATA DIY

I have alldata and can confirm it has all the diagrams you might need. Good luck!
Can you send me the diagram? Jk lol I’ll look into it, thanks!
Can you send me the diagram? Jk lol I’ll look into it, thanks!
They are accessed under license and transmitting them is a felony. Will alldatadiy prosecute? Doubtful but I'm surely not spending 5 years in prison to save you 20 bucks! Best I can do is direct you to instant access.
They are accessed under license and transmitting them is a felony. Will alldatadiy prosecute? Doubtful but I'm surely not spending 5 years in prison to save you 20 bucks! Best I can do is direct you to instant access.
Here’s an update. I got the instrument panel “working” not really but I get it somewhat working. It powers up but that's it, nothing else works, will have another update if I make progress
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It powers up but that's it, nothing else works, will have another update if I make progress
The power pin is the same - at least that's a start!
The power pin is the same - at least that's a start!
I also hooked up the can bus, I forgot to mention that
At first, we all said, "Nah, you can't do that, or that, or that."

And here you are doing it!
At first, we all said, "Nah, you can't do that, or that, or that."

And here you are doing it!
If theres a will theres a way! But it’s still a work in progress, will update when more progress is made. maybe with some help of you guys it can be done. The issue I think I’m having is the new cluster has MOST serial data and the old one doesn’t. If I could get a explanation of what MOST serial data is this might actually work
The MOST data network is a dedicated high speed multimedia streaming data bus independent from GMLAN. The MOST bus will be configured in a physical hardwired loop with each device within the bus sends and receives data on an assigned MOST addresses in a set order. Each device on the MOST bus will be required to have twisted pair copper wires (2 transmit TX, 2 receive RX, and 1 electronic control line which is a 12 V wakeup signal line).

The Radio is the MOST Master and will monitor the bus for vehicle configuration, Infotainment data messages, ECM/BCM checksum and errors on the bus. The MOST initialization consists of a short 100 ms low voltage pulse on the electronic control line (or MOST control line) connected to all devices contained on the MOST ring. This wakeup message once received by each device, will first respond with a generic device response. Once these initial responses on the MOST bus are reported successfully without error to the Radio, the second data request will record the MOST device addresses, their functionality requirements and capabilities within. The Radio will learn this information and also record the address node sequence on the MOST bus at this point. This node address list will now be stored within the Radio as the MOST bus configuration (called “Last Working MOST ID of Node 1 – 9” on scan tool data display).

When MOST receive, transmit, or control line faults are detected, transmit/receive messages will not received as expected from the wakeup request. The Radio and the Human Machine Interface Control Module will then perform diagnostics to isolate these MOST faults. If the MOST control line is shorted low to 0 V for excess amount of time, the Radio will set a U2098 DTC and Human Machine Interface Control Module will set a U0029 02 DTC. At this point the MOST bus will be unable to communicate until the shorted MOST control line is repaired.

Once the shorted MOST control line diagnostics pass, the Radio will attempt to resend the initial short pulse attempts up to 3 times on the MOST control line. If the expected responses are not received, the Radio continues into a failure mode setting a U0028 DTC and will continue on to send one 300 ms long pulse, which will enable the furthest upstream transmitting device to become the surrogate MOST Master in this MOST fault/diagnostic mode. When the Radio receives this new MOST Master identity, the surrogate MOST master device be identified based on scan tool data parameter “Surrogate MOST Master Node Upstream Position”. The scan tool should be used to determine the MOST bus configuration and direction by utilizing the “Last Working MOST ID of Node 1 – 9” parameters from the Radio data display. When a fault is present, it will indicate the newly enabled “Surrogate MOST Master Node Upstream Position” from the Radio. This will assist in determining where the MOST bus/control is at fault. The MOST device upstream from the surrogate MOST master device, transmit, receive, or control lines will be the suspect areas for diagnostics at this point. These faults can be associated with any of the MOST transmit, receive, or control line twisted copper wires or possibly an internal device fault.

The Human Machine Interface Control Module will set a U0029 00 DTC when it diagnoses a MOST bus not communicating properly after one attempt. When the DTC U0029 00 is set by the Human Machine Interface Control Module without the corresponding DTC U0028 from the Radio, it will be an indication of an intermittent wiring/device condition.
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The MOST data network is a dedicated high speed multimedia streaming data bus independent from GMLAN. The MOST bus will be configured in a physical hardwired loop with each device within the bus sends and receives data on an assigned MOST addresses in a set order. Each device on the MOST bus will be required to have twisted pair copper wires (2 transmit TX, 2 receive RX, and 1 electronic control line which is a 12 V wakeup signal line).

The Radio is the MOST Master and will monitor the bus for vehicle configuration, Infotainment data messages, ECM/BCM checksum and errors on the bus. The MOST initialization consists of a short 100 ms low voltage pulse on the electronic control line (or MOST control line) connected to all devices contained on the MOST ring. This wakeup message once received by each device, will first respond with a generic device response. Once these initial responses on the MOST bus are reported successfully without error to the Radio, the second data request will record the MOST device addresses, their functionality requirements and capabilities within. The Radio will learn this information and also record the address node sequence on the MOST bus at this point. This node address list will now be stored within the Radio as the MOST bus configuration (called “Last Working MOST ID of Node 1 – 9” on scan tool data display).

When MOST receive, transmit, or control line faults are detected, transmit/receive messages will not received as expected from the wakeup request. The Radio and the Human Machine Interface Control Module will then perform diagnostics to isolate these MOST faults. If the MOST control line is shorted low to 0 V for excess amount of time, the Radio will set a U2098 DTC and Human Machine Interface Control Module will set a U0029 02 DTC. At this point the MOST bus will be unable to communicate until the shorted MOST control line is repaired.

Once the shorted MOST control line diagnostics pass, the Radio will attempt to resend the initial short pulse attempts up to 3 times on the MOST control line. If the expected responses are not received, the Radio continues into a failure mode setting a U0028 DTC and will continue on to send one 300 ms long pulse, which will enable the furthest upstream transmitting device to become the surrogate MOST Master in this MOST fault/diagnostic mode. When the Radio receives this new MOST Master identity, the surrogate MOST master device be identified based on scan tool data parameter “Surrogate MOST Master Node Upstream Position”. The scan tool should be used to determine the MOST bus configuration and direction by utilizing the “Last Working MOST ID of Node 1 – 9” parameters from the Radio data display. When a fault is present, it will indicate the newly enabled “Surrogate MOST Master Node Upstream Position” from the Radio. This will assist in determining where the MOST bus/control is at fault. The MOST device upstream from the surrogate MOST master device, transmit, receive, or control lines will be the suspect areas for diagnostics at this point. These faults can be associated with any of the MOST transmit, receive, or control line twisted copper wires or possibly an internal device fault.

The Human Machine Interface Control Module will set a U0029 00 DTC when it diagnoses a MOST bus not communicating properly after one attempt. When the DTC U0029 00 is set by the Human Machine Interface Control Module without the corresponding DTC U0028 from the Radio, it will be an indication of an intermittent wiring/device condition.
Is there any way to replicate it or bypass it completely? If not will the system still work without some computers? I have the radio, info display, cluster, and the XM computer? Not sure if it would work with just those
Is there any way to replicate it or bypass it completely? If not will the system still work without some computers? I have the radio, info display, cluster, and the XM computer? Not sure if it would work with just those
All good questions. The jump from having power to communication it can understand seems unlikely but perhaps it can get close enough. I would think the HMI module will be needed... the MOST description mentions it quite a bit.
All good questions. The jump from having power to communication it can understand seems unlikely but perhaps it can get close enough. I would think the HMI module will be needed... the MOST description mentions it quite a bit.
Ok, I’ll see if I can working without the HMI module. From what I can see, the MOST bus controls the gauges, ABS, traction control, and the emergency brake. Because that’s all that wasn’t working with just the low speed serial data connected. Lmk if I’m wrong
Ok, so I now have all the dash computers. I’m putting 12 volts to the fuse box in the dash. I have power on some fuses but not all. Also I have no power to any computer. I’ve messed with it for a while and no luck with power anywhere. Please help.
By having all of the dash computers do you mean you have the gen9 HMI module, BCM, HVAC module... etc? You still have power to the instrument panel but no power to any of the other modules?
By having all of the dash computers do you mean you have the gen9 HMI module, BCM, HVAC module... etc? You still have power to the instrument panel but no power to any of the other modules?
Yes, but not sure about the HVAC. No power to the instrument panel. Or anywhere beside the fuse box
Hopefully someone will come along to help you. I have no idea how this could work. There are just so many things that are problematic. Example: The gen7 has no auto stop but the gen9 tach does. Will your ECM send info that doesn't include bits for auto stop and will this interpret that info as a gen9 that has it disabled? Or does the Auto Stop position just become 500 rpm and 500 becomes 1000... 🤷‍♂️
Hopefully someone will come along to help you. I have no idea how this could work. There are just so many things that are problematic. Example: The gen7 has no auto stop but the gen9 tach does. Will your ECM send info that doesn't include bits for auto stop and will this interpret that info as a gen9 that has it disabled? Or does the Auto Stop position just become 500 rpm and 500 becomes 1000... 🤷‍♂️
Well my plan is to have code learn what the 7th gen serial data is and convert that to the most Bus and I probably will have a Arduino control it. Might have to have the code modified the account for the auto stop.
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