Question

How to fix the code U2105 on my 2005 Saturn Vue 3.5L? The vehicle starts and then stops I/p lights work no gauges

Answer 1

U2105 will be set if the TCM has lost communication with the ECM, Each of these modules sends information high and low  pulse with each other over a can bus line, If the TCM has not received ECM data for a specific amount of time DTC 2105 will set, Loss of communication can be from the can bus line being open, short to voltage, to a faulty ground on either module

U2105 Saturn Code - Lost Communications with Engine Control Module
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