4.3L V8RWDAUTOMATICgas
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P1600moderate severityPowertrain

ECM Battery Backup Circuit

on 2006 Lexus GS 430 4.3L V8 · RWD

What this code means

The ECM detected a loss of battery voltage at the BATT terminal.

Symptoms

  • CEL
  • Lost fuel trim values
  • Intermittent stalling
  • Difficulty starting

Common causes

  • Corroded battery terminals
  • Damaged EFI fuse
  • Open BATT wiring
  • Weak battery

Diagnostic steps

  1. Check battery terminals
  2. Test EFI fuse
  3. Inspect BATT wiring
  4. Check battery voltage

Repair notes

Clean terminals or replace fuse.

Other Powertrain codes on this vehicle

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