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2021 FORD MUSTANG MACH-E

Standard Range Dual Motor AWDRWDAUTOMATICev
Repairs0Labor423Torque4167Fluid6DTC581Battery1Maintenance0Recalls0
U0073critical severityNetwork

Control Module Communication Bus A Off

on 2021 Ford Mustang Mach-E Standard Range Dual Motor AWD · RWD

What this code means

CAN bus A is not communicating. Complete loss of communication on the primary bus.

Symptoms

  • Multiple systems down
  • Multiple warning lights
  • Vehicle may not start
  • No scan tool communication

Common causes

  • CAN bus wiring shorted or open
  • Termination resistor failure
  • Module failure shorting the bus
  • Major wiring harness damage

Diagnostic steps

  1. Check CAN bus voltage levels
  2. Measure bus resistance
  3. Isolate bus segments
  4. Check for physical damage to wiring

Repair notes

Major network failure. Systematic diagnosis required.

Other Network codes on this vehicle

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