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P0AA1

Hybrid Battery Positive Contactor Circuit

BMS detects an electrical fault in the positive HV contactor coil circuit. The contactor connects the battery positive terminal to the high-voltage bus.

  • Check engine light: Yes
  • Emissions related: No
  • Repair difficulty: shop_only

Common causes

Ordered by how often each turns out to be the cause.

  • Contactor coil openCommon
  • Wiring faultPossible

Parts involved

  • Hv Contactor Positive
  • Bms
  • Wiring Harness

P0AA1 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.