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U0100 Diagnostic Trouble Code Discussion for October 2022

Lost Communication With ECM


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Trouble Ticket Help Requests for DTC U0100
Help Request Posted
2005 Cadillac CTS 3.6L No Start, No ECM communication VIN: 1G6DP567X5
U0100: Lost Communication With Engine Control Module. We thought we had a "typical" ECM failure on this CTS and had just repaired another 05 CTS with reman ECM a few days before this nightmare. Key on, no check engine light, no communication. Key stuck in igntion. We ran through the GM service bulleti...
October 14, 2022
2005 Cadillac CTS 3.6L No Start, No ECM communication VIN: 1G6DP567X5
U0100: Lost Communication With Engine Control Module. We thought we had a "typical" ECM failure on this CTS and had just repaired another 05 CTS with reman ECM a few days before this nightmare. Key on, no check engine light, no communication. Key stuck in igntion. We ran through the GM service bulleti...
October 17, 2022