SOLVED! 2006 GMC Sierra Denali Engine Swap "No IPC, No Start, U1000 Code"


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2006 GMC Sierra 1500 Denali with “No Communication” Code U1000 after Engine Swap:

Helpful Tools of Choice for Best Results:

(1) Print Out ALL Class 2 Network Diagrams for correct YMM of Vehicle.
(2) DMM with Extra Back-Probe Pins and Test Leads.
(3) Quality Scanner (note that a Blue Tooth Scanner May NOT Work).
(4) 16 Pin DLC Break-Out Box with Dual DLC Cable Connections.
(5) Class 2 Network Splice Pack (SP-205) Multi-Lead Module Signal Combo Harness.
(6) Oscilloscope (Your Choice of either a PICO-Scope, Hantek or High End Autel).
(7) Lighted Pin Probe for Testing Powers & Grounds.

Post Engine Swap “No Dash Lights, No Gauges & No Start” Diagnostic Procedures:

(1) Determine a Complete Lack of Communication on the Class 2 Network via Code U1000.
(2) Check Scope for Modules Communication on Scanner looking for 0-7 Hall Effect Square Wave.
(3) Measure for "Short To Power @ around 10 Volts DC on the MAP Sensor 5 Volt Ref. Wire with DMM.
(4) Pull the “Under-Dash” Splice Pack and Hook up Multi-Lead Module Signal Wire Harness to Break-Out Box.
(5) Once Comms Restored, Check for a Code Thrown for a Failed Generator - Battery Control Module.
(6) Check for Communication Capability with JUST the PCM.
(7) Confirm Powers & Grounds AFTER Checking ALL Ground Wire(s) Engine & Body Connection Integrity.
(8) Note that the Generator-Battery Control Module AND the PCM share G-103 as a Common Ground.
(9) Check for possible Engine Swap Oversight of Failing to Install G-103 Ground at back of (R) Engine Head.
(10) Ping ALL Modules to Double Check for any OTHER Module incompatibility Issues.

Another Related “SOLVED!” Class 2 Communications Thread:
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