Okay. We are making progress. Hopefully I can explain this in clear terms because this is confusing.
You have a CAN bus network. This is an electrical network that allows the modules to communicate with each other. The voltage on this network needs to be correct or you will get the message of no bus like you are.
These two wires that you checked are the CAN C portion and you have the second portion called interior high speed bus (IHS). Take a look at the first attachment and it illustrates this a little more.
We now need to go to the back of the TIPM under the hood and back probe these specific networks and then unhook connectors (as you were) while watching these network voltages. Clearly you only have one meter so we can only do one at a time. So I want you too measure each wire individually and then let me know what they are. So that is four wires. The CAN C wires should equal 5 volts and be about 2.7 and 2.3 volts. About the same for the CAN IHS.
Based on what you found already, I imagine they are going to be low and then we will just pick one to look at when you are disconnecting connectors. When this voltage returns to normal, you will have just disconnected the issue. Either that specific connector or something down stream of it is the issue. We need to limit this down so that we can make it more manageable to find the issue.
On the back of the TIPM you will find connectors. You want C7 Pins 28 and 29 for CAN C. Then PIN 26 and 27 for IHS.
I am sure you have questions but if you can just get those voltages with the key on we can take the next step. Thanks
Images (Click to enlarge)
Sunday, November 3rd, 2019 AT 4:10 PM