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U0100 Diagnostic Trouble Code Discussion for November 2012

Lost Communication With ECM

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Trouble Ticket Help Requests for DTC U0100
Help Request Posted
2007 Toyota Tundra SR5 5.7L No Start VIN: 5TFRV541X7
U0100: loss comm. with ecm/pcm a. Here is one for the Toyota tech's. This truck died while driving, no start, spins ok, no ses at all, when I check with the techstream, ecu will not respond. Question is, do these trucks have issues with ecu's dieing like this or with power loss thru relays may...
November 06, 2012
2007 Toyota Tundra SR5 5.7L No Start VIN: 5TFRV541X7
U0100: no communication. Hey all, had this vehicle in for a few days. Died while driving, spins ok, no start. Has no ses light, no communication with ecm. Went thru diagnostic charts. Checked all power and grounds to ecm. All good, ordered new ecm from toyota, installed. Still no comm...
November 20, 2012