From Ross-Tech Wiki

17606/P1198 - Oxygen (Lambda) Sensor Heater Circuit: B1 S2: Electrical Malfunction

Possible Causes

  • Failed O2 sensor heater circuit
  • Wiring Harness issue
  • Failing ECM

Possible Solutions

  • Inspect and test O2 sensor heater circuit as per repair manual
  • Inspect and test wiring harness as per wiring diagram
  • Replace ECM if O2 sensor and wiring harness are to factory design

Special Notes

On V6 engines, B1S2 and B2S2 can share a common ground though the ECM, see wiring diagram