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P0064 — HO2S Heater Control Circuit High Bank 2 Sensor 3

Detailed page for trouble code P0064.

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Code

P0064

Generic P — Powertrain

HO2S Heater Control Circuit High Bank 2 Sensor 3

Brand: Generic
Views: UK: 19 EN: 58 RU: 37
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open or damaged heater element inside the oxygen sensor
  • Broken, corroded or disconnected wiring or connector for the heater circuit
  • Short to battery voltage (power feed) in the heater control wiring
  • Blown fuse or failed relay supplying the sensor heater
  • Poor engine/chassis ground affecting heater circuit
  • Faulty PCM or driver output (less common)

Symptoms

  • Check Engine Light (MIL) illuminated
  • Stored P0064 (may be accompanied by other O2 heater codes)
  • Failed emissions readiness for oxygen sensor heater
  • Reduced fuel trim accuracy and possible drivability complaints (in some cases)
  • Possible poorer fuel economy

What to check

  • Read and record freeze frame and related DTCs with a scan tool
  • Visual inspection of the Bank 2 Sensor 3 harness and connector for damage, corrosion, heat damage, or contamination
  • Verify fuses and relays for the oxygen sensor heater circuit
  • Backprobe the sensor connector to check for heater supply voltage (battery) and control signal
  • Measure heater element resistance at the sensor (compare to spec)
  • Check for continuity to battery positive (short to power) and continuity to ground (short to ground or open)

Signal parameters

  • Heater supply voltage: ~11–14 V (battery voltage) at the heater power feed with ignition ON
  • Heater element resistance (typical): low single-digit to tens of ohms (commonly in the 2–20 Ω range; vehicle-specific)
  • When PCM commands heater ON: control path should complete and allow current flow (measurable current draw; exact current depends on sensor design)
  • Open/high resistance or high voltage on the control line indicates a fault in the heater circuit

Diagnostic algorithm

  1. Verify the code: retrieve freeze-frame data and any related O2 heater or oxygen sensor codes.
  2. Visual inspection: examine the Bank 2 Sensor 3 connector and wiring for corrosion, loose terminals, heat damage, cuts, or rodent chew. Repair any obvious damage.
  3. Check fuses/relays: locate and test the fuse(s) and relay(s) that feed the O2 heater circuits; replace if blown/faulty.
  4. Backprobe connector: with ignition ON (engine off), backprobe the sensor connector to identify the heater power feed and the PCM control/monitor circuit. Confirm battery voltage on the supply feed.
  5. Measure heater resistance: disconnect sensor and measure resistance across the heater pins at the sensor. If open or well above spec, replace the sensor.
  6. Check for shorts/opens: with harness disconnected, check continuity from the sensor connector to the fuse/relay and to the PCM. Check for short to battery (unexpected continuity to B+) or short to ground where not expected.
  7. Command heater on: using a capable scan tool, command the heater ON and observe voltage/current behavior; verify the PCM driver is switching as expected.
  8. Repair wiring or replace sensor: repair damaged wiring, clean/replace connector, or replace the oxygen sensor heater if out of spec. Use OEM or equivalent replacement sensor.
  9. Clear codes and verify: clear DTCs, perform drive cycle / road test and recheck for code reappearance and readiness status. If code returns and wiring and sensor test good, consider PCM diagnosis.

Likely causes

  • Sensor heater element failed (open or high resistance)
  • Connector pins corroded or pushed out
  • Wiring harness damaged by heat, chafing, or rodent damage
  • Fuse for heater circuit blown or relay stuck
  • Short to Vb (battery) on the control/feedback circuit

Fault status

⚠️ Status
Heated oxygen sensor (HO2S) heater control circuit voltage high for Bank 2 Sensor 3 — indicates open/high-resistance heater circuit, short to voltage, bad connector/fuse, or control module issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

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Code

P0064

LAND ROVER P — Powertrain

Heated control circuit of the oxygen sensor heater high (bank 2, sensor 3)

Views: UK: 10 EN: 14 RU: 17
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open or damaged heater element inside the oxygen sensor
  • Broken, corroded or disconnected wiring or connector for the heater circuit
  • Short to battery voltage (power feed) in the heater control wiring
  • Blown fuse or failed relay supplying the sensor heater
  • Poor engine/chassis ground affecting heater circuit
  • Faulty PCM or driver output (less common)

Symptoms

  • Check Engine Light (MIL) illuminated
  • Stored P0064 (may be accompanied by other O2 heater codes)
  • Failed emissions readiness for oxygen sensor heater
  • Reduced fuel trim accuracy and possible drivability complaints (in some cases)
  • Possible poorer fuel economy

What to check

  • Read and record freeze frame and related DTCs with a scan tool
  • Visual inspection of the Bank 2 Sensor 3 harness and connector for damage, corrosion, heat damage, or contamination
  • Verify fuses and relays for the oxygen sensor heater circuit
  • Backprobe the sensor connector to check for heater supply voltage (battery) and control signal
  • Measure heater element resistance at the sensor (compare to spec)
  • Check for continuity to battery positive (short to power) and continuity to ground (short to ground or open)

Signal parameters

  • Heater supply voltage: ~11–14 V (battery voltage) at the heater power feed with ignition ON
  • Heater element resistance (typical): low single-digit to tens of ohms (commonly in the 2–20 Ω range; vehicle-specific)
  • When PCM commands heater ON: control path should complete and allow current flow (measurable current draw; exact current depends on sensor design)
  • Open/high resistance or high voltage on the control line indicates a fault in the heater circuit

Diagnostic algorithm

  1. Verify the code: retrieve freeze-frame data and any related O2 heater or oxygen sensor codes.
  2. Visual inspection: examine the Bank 2 Sensor 3 connector and wiring for corrosion, loose terminals, heat damage, cuts, or rodent chew. Repair any obvious damage.
  3. Check fuses/relays: locate and test the fuse(s) and relay(s) that feed the O2 heater circuits; replace if blown/faulty.
  4. Backprobe connector: with ignition ON (engine off), backprobe the sensor connector to identify the heater power feed and the PCM control/monitor circuit. Confirm battery voltage on the supply feed.
  5. Measure heater resistance: disconnect sensor and measure resistance across the heater pins at the sensor. If open or well above spec, replace the sensor.
  6. Check for shorts/opens: with harness disconnected, check continuity from the sensor connector to the fuse/relay and to the PCM. Check for short to battery (unexpected continuity to B+) or short to ground where not expected.
  7. Command heater on: using a capable scan tool, command the heater ON and observe voltage/current behavior; verify the PCM driver is switching as expected.
  8. Repair wiring or replace sensor: repair damaged wiring, clean/replace connector, or replace the oxygen sensor heater if out of spec. Use OEM or equivalent replacement sensor.
  9. Clear codes and verify: clear DTCs, perform drive cycle / road test and recheck for code reappearance and readiness status. If code returns and wiring and sensor test good, consider PCM diagnosis.

Likely causes

  • Sensor heater element failed (open or high resistance)
  • Connector pins corroded or pushed out
  • Wiring harness damaged by heat, chafing, or rodent damage
  • Fuse for heater circuit blown or relay stuck
  • Short to Vb (battery) on the control/feedback circuit

Fault status

⚠️ Status
Heated oxygen sensor (HO2S) heater control circuit voltage high for Bank 2 Sensor 3 — indicates open/high-resistance heater circuit, short to voltage, bad connector/fuse, or control module issue.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

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Your experience will help others
+100 karma for a short comment :)
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