Help request: Main Body ECU schematic?

It’s hard to tell what he has done…

 

The OP's symptoms match up to a "partial" LIN bus failure. I had "the exact same problem" on a 2011 Sienna.

Windows would function from their satellite switches, but not from the master. Kinda sorta got comm with the door modules. Codes but no data or bidirectional controls.

In my case there was corrosion at a door connector that pulled the LIN voltage down - just a little bit. Static testing showed a few mega ohms to ground but it acted different when it was powered up (and was worse when ambient humidity went up)

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Funny how that can even happen. Sure enough, the diagram shows each window regulator having both a LIN connection, and direct button inputs from the local switch. Even the driver's door regulator works that way.

But the master switch lockout button status only gets sent over LIN, so with a flaky LIN bus it might also be interesting to see if the local switches can be properly locked out from the master.

 

Depends on how bad the LIN is at any given moment. On the Sienna it seemed that it would default to satellite switch function IF there was total loss of comm.

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Even funnier. The diagram shows the fused circuits supplying the window regulators are all unswitched; the regulators have power all the time, and must depend on a LIN message telling them "hey, act like the car's off" when the car's off.

 

Yep. The scope waveform of the LIN looked like "normal" activity. However, instead of being at almost battery voltage, the (receptive) signal voltage was a volt+ below that. Just at the lower threshold of "logic high" voltage.

I ended up watching the LIN voltage and unplugged harness connectors until I saw the voltage go up - then followed that circuit branch until I found green death.

I would expect the OP has something like that, a high resistance short to ground on the LIN circuit somewhere.

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Of course that's most useful when it turns out there is a common failure point for such symptoms, and not, say, corrosion creating a fault on the LIN bus somewhere that owners all have to find for themselves. Some issues are like that.