Power Solutions, Inc.

221

UnclassifiedGeneral

What This Code Means

DST displays HO2S voltage fixed below 0.35 volts after 2 minutes of idle run time

Possible Causes

  • •Closed Loop multiplier exceeds the limits of normal operation
  • •Closed Loop multiplier out of range (at limit of 35%)
  • •Continuity between HO2S connector signal pin B and HO2S sensor ground pin A
  • •Continuity between HO2S connector signal pin B and engine ground
  • •Faulty HO2S sensor
  • •Multiplier cannot correctly modify the fuel flow within its limits

Suggested Actions

  1. 1Clear DTC information from the ECM using DST and re-test engine operation
  2. 2Perform On-Board (OBD) System Check
  3. 3Refer to Diagnostic aids for DTC 221
  4. 4Repair circuit between HO2S connector signal pin B and HO2S sensor ground pin A as required (refer to Wiring Repairs in Engine Electrical)
  5. 5Repair circuit between HO2S connector signal pin B and engine ground as required (refer to Wiring Repairs in Engine Electrical)
  6. 6Replace HO2S sensor

Related Power Solutions, Inc. Fault Codes

224262212511211516142555135-BP556134-BP635
Browse all Power Solutions, Inc. fault codes

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