LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2000 >> Contour SE, 2.5 L, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 1328 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC P0135: O2 Heater Circuit (Bank 1, Sensor 1)

DTC P0135: O2 Heater Circuit (Bank 1, Sensor 1)

WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2006 Mercury Mountaineer, 2006 Mercury Monterey, 2006 Mercury Montego, 2006 Mercury Mariner, and 2006 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.
P0135 - O2 HEATER CIRCUIT (BANK 1, SENSOR 1)

Description:  During testing the heated oxygen sensor (HO2S) heaters are checked for open and short circuits and excessive current draw. The test fails when the current draw exceeds a calibrated limit or an open or short circuit is detected.
Possible Causes: 
  • Vacuum hose disconnected on exhaust gas recirculation (EGR) system module (ESM) applications
  • Short to VPWR in the harness or HO2S
  • Water in the harness connector
  • Open VPWR circuit
  • Open GND circuit
  • Low battery voltage
  • Corrosion or incorrect harness connections
  • Damaged HO2S heater
Diagnostic Aids:  Check the HO2S electrical connector for damage, corrosion, and water intrusion. Damaged HO2S heater.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test DW .
scientia non olet · About LEMON Manuals