TRNW-2: Update: 6t40 can bus diagnosing

[Justin Merritt]

I have tried to send a reply to the original post, but it doesn't seem to
be coming through the mailer, anyway here is an update.

I'm back at diagnosing this car this morning.  So all the replies so far
have been very helpful in making my mind understand what I am testing.
Dan's wiring diagram that he posted this morning is the same that I was
using yesterday to try to diagnose.  His explanation of where to test at
the tcm connector and what I should be getting for ohm readings made the
most sense to me on how to test and which direction the harness I wanted to
go.  First thing I accidentally found by testing resistance at the techm
connector is that the wiring diagram is WRONG!  PIN 7&8 run toward the
power steering module and 6&14 go to the ECM.  I was looking for the
terminating resistors in each direction that Dan pointed out, and I ran
upon that diagram mistake.  Now that I have a better understanding of what
I am looking for by testing, I know which way to work.  From my Techm, I
have the 120 ohms to the ecm, but I have an open circuit on 7&8 to the
power steering module.  I go to the power steering module and test
continuity and my terminating resistors in both directions, and I have
them.  So it seems my problem is the data line running through the rack and
pinion power steering module.  I jumper wired the data lines at the power
steering module and I now have communication with my ecm and tcm.  Thanks
for all the replies, I have tried to keep up with reading and classes on
the CAN Bus stuff, but I never fully understood it until this real world
experience.  Now to locate a rack and pinion and get this car going.

Thanks Again
Justin
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