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Home >> Jeep >> 2004 >> Wrangler X, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Powertrain Diagnostic Procedures >> DRIVEABILITY - Gas >> DTC P0136: O2 Sensor 1/2 Heater Circuit Malfunction >> Possible Causes
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Possible Causes

  1. GOOD TRIP EQUAL TO ZERO
  2. O2 SENSOR HEATER RELAY
  3. (F142) FUSED ASD RELAY OUTPUT CIRCUIT
  4. (K512) O2 HEATER RELAY CONTROL CIRCUIT OPEN
  5. (K512) O2 HEATER RELAY CONTROL CIRCUIT SHORTED TO GROUND
  6. O2 HEATER ELEMENT
  7. (A242) O2 HEATER RELAY OUTPUT CIRCUIT
  8. PCM