Okay. That helps. I suspect you have two issues. However, the cause of the draw could be the cause of the no bus issue. That 40 amp fuse is what we call a mega fuse. It not only runs the interior lamps but it runs the mirrors, radio, exterior lamps, etc. Basically anything that is on fuses 1, 2, 4, and 13 in the junction block. So this 40 fuse is the larger fuse for those smaller fuses. Something on those fuses is causing your draw.
As for the no bus message, that is telling you that one of the modules is not able to communicate and the fact that the vehicle does not start and run, chances are that it is the PCM. I attached information on this bus system as it is called a PCI bus so it is different then a CAN bus. On this bus there is only one dominant module which is the PCM where in CAN bus systems you have two dominant modules and they are the only terminating modules. Where as each module in the PCI bus terminates itself.
So here is what I would recommend. Plug the 40 amp fuse back in and monitor the draw again on the negative battery terminal to get your 1.5 amp draw back. Then go to the junction block and remove fuse 1, 2, 4, and then 13 to see which one causes the draw go away. Once we know that we can drill further into what that fuse controls.
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Sunday, October 18th, 2020 AT 6:20 PM