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Home / DTC / P0135 — Defective Oxygen Sensor/Air Fuel Ratio Sensor, defective Oxygen Sensor/Air Fuel Ratio Sensor Heater Circuit, Exhaust System Leak, Intake Air System leak, Low Fuel Pressure, Defective Engine Coolant Temperature Sensor, Defective sensor wiring and or circuit problem, PCM software needs to be updated, Defective PCM

P0135 — Defective Oxygen Sensor/Air Fuel Ratio Sensor, defective Oxygen Sensor/Air Fuel Ratio Sensor Heater Circuit, Exhaust System Leak, Intake Air System leak, Low Fuel Pressure, Defective Engine Coolant Temperature Sensor, Defective sensor wiring and or circuit problem, PCM software needs to be updated, Defective PCM

Detailed page for trouble code P0135.

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Code

P0135

AUDI P — Powertrain

Defective Oxygen Sensor/Air Fuel Ratio Sensor, defective Oxygen Sensor/Air Fuel Ratio Sensor Heater Circuit, Exhaust System Leak, Intake Air System leak, Low Fuel Pressure, Defective Engine Coolant Temperature Sensor, Defective sensor wiring and or circuit problem, PCM software needs to be updated, Defective PCM

Brand: AUDI
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed O2 sensor heater element
  • Open or shorted heater circuit wiring (power or ground)
  • Blown fuse or faulty relay supplying heater circuit
  • Corroded/poor connector or pin contact at sensor or harness
  • PCM driver fault or internal short
  • Aftermarket or incorrect sensor installed

Symptoms

  • Check Engine Light (MIL) illuminated with P0135 stored
  • Heater-related readiness monitor incomplete or in fault
  • Long cold start enrichment / poor emissions until engine warms up
  • Lower fuel economy or rough idle until sensor warms
  • Elevated tailpipe emissions (failed emissions test)
  • Possible intermittent MIL if wiring or connector is intermittent

What to check

  • Retrieve freeze frame and live data with a diagnostic scan tool (confirm Bank 1 Sensor 1 identification)
  • Verify vehicle-specific code is P0135 (heater circuit) and check readiness status
  • Visually inspect sensor, wiring, and connector for damage, corrosion, melted insulation, or exhaust soot
  • Check fuses and relays related to O2 sensor heaters
  • Backprobe heater power and ground pins with ignition ON (engine off) to confirm supply voltage and control ground per factory wiring diagrams
  • Measure heater resistance at sensor with connector disconnected and compare to specification

Signal parameters

  • Heater resistance (cold): typically 2–20 ohms depending on sensor; consult Audi spec
  • Heater supply voltage: battery voltage (approx. 12 V) with ignition ON (engine off)
  • Heater control: PCM provides ground switching or a fused supply feed — verify switching behavior with scope or DVOM
  • O2 sensor voltage (post-heater warmup): switching ~0.1–0.9 V in rich/lean cycles for narrowband sensors
  • Heater current draw: expected few hundred mA; abnormally high indicates short, open indicates open circuit

Diagnostic algorithm

  1. Connect a scan tool, confirm P0135 and identify Bank 1 Sensor 1. Record freeze frame and readiness status.
  2. Perform a visual inspection of the sensor, connector, and wiring harness for damage, corrosion, rodent chew, or heat damage.
  3. With ignition OFF, disconnect sensor connector. Measure heater element resistance across heater pins; compare to Audi spec. If within spec, proceed; if open/infinite or shorted, replace sensor.
  4. With connector disconnected and ignition ON (engine off), measure heater supply voltage at harness pin. If no supply, check related fuses/relays and wiring back to power source.
  5. With connector disconnected, backprobe heater ground/control pin and monitor while cranking or with engine running if required per OEM procedure; verify PCM provides ground switching (or supply) as specified.
  6. If supply and control are present but heater resistance out of range, replace sensor. If heater resistance is correct but no switching/ground from PCM, inspect wiring for opens/shorts and repair. Check for shorts to battery or ground.
  7. If wiring and connectors are good but PCM does not command the heater, check for relevant fuse/relay and then consider PCM output testing or software update per Audi service info; contact dealer for confirmed software/TSB.
  8. After repair or replacement, clear codes, perform drive cycle or forced readiness, and confirm code does not return. Verify proper sensor switching and heater operation with live data.
  9. If intermittent, wiggle-test harness, inspect for chafing, and consider securing wiring; use smoke test to detect exhaust leaks that could influence sensor behavior.

Likely causes

  • Failed oxygen sensor heater (most common)
  • Damaged sensor connector (corrosion or water intrusion)
  • Broken or shorted heater supply/ground wire between sensor and PCM
  • Blown fuse or faulty fuse link for heater circuit
  • PCM heater driver failure (less common)

Fault status

⚠️ Status
P0135 — Oxygen Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction. Heater circuit failed to operate within expected parameters; sensor may not reach operating temperature.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5 - 2.0 hours

Similar codes

P0141 P0155 P0130 P0131 P0132 P0133
Repair manuals

Manual library for AUDI

1,243

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Code

P0135

Generic P — Powertrain

O2 Sensor Heater Circuit Bank 1 Sensor 1

Brand: Generic
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed O2 sensor heater element
  • Open or shorted heater circuit wiring (power or ground)
  • Blown fuse or faulty relay supplying heater circuit
  • Corroded/poor connector or pin contact at sensor or harness
  • PCM driver fault or internal short
  • Aftermarket or incorrect sensor installed

Symptoms

  • Check Engine Light (MIL) illuminated with P0135 stored
  • Heater-related readiness monitor incomplete or in fault
  • Long cold start enrichment / poor emissions until engine warms up
  • Lower fuel economy or rough idle until sensor warms
  • Elevated tailpipe emissions (failed emissions test)
  • Possible intermittent MIL if wiring or connector is intermittent

What to check

  • Retrieve freeze frame and live data with a diagnostic scan tool (confirm Bank 1 Sensor 1 identification)
  • Verify vehicle-specific code is P0135 (heater circuit) and check readiness status
  • Visually inspect sensor, wiring, and connector for damage, corrosion, melted insulation, or exhaust soot
  • Check fuses and relays related to O2 sensor heaters
  • Backprobe heater power and ground pins with ignition ON (engine off) to confirm supply voltage and control ground per factory wiring diagrams
  • Measure heater resistance at sensor with connector disconnected and compare to specification

Signal parameters

  • Heater resistance (cold): typically 2–20 ohms depending on sensor; consult Audi spec
  • Heater supply voltage: battery voltage (approx. 12 V) with ignition ON (engine off)
  • Heater control: PCM provides ground switching or a fused supply feed — verify switching behavior with scope or DVOM
  • O2 sensor voltage (post-heater warmup): switching ~0.1–0.9 V in rich/lean cycles for narrowband sensors
  • Heater current draw: expected few hundred mA; abnormally high indicates short, open indicates open circuit

Diagnostic algorithm

  1. Connect a scan tool, confirm P0135 and identify Bank 1 Sensor 1. Record freeze frame and readiness status.
  2. Perform a visual inspection of the sensor, connector, and wiring harness for damage, corrosion, rodent chew, or heat damage.
  3. With ignition OFF, disconnect sensor connector. Measure heater element resistance across heater pins; compare to Audi spec. If within spec, proceed; if open/infinite or shorted, replace sensor.
  4. With connector disconnected and ignition ON (engine off), measure heater supply voltage at harness pin. If no supply, check related fuses/relays and wiring back to power source.
  5. With connector disconnected, backprobe heater ground/control pin and monitor while cranking or with engine running if required per OEM procedure; verify PCM provides ground switching (or supply) as specified.
  6. If supply and control are present but heater resistance out of range, replace sensor. If heater resistance is correct but no switching/ground from PCM, inspect wiring for opens/shorts and repair. Check for shorts to battery or ground.
  7. If wiring and connectors are good but PCM does not command the heater, check for relevant fuse/relay and then consider PCM output testing or software update per Audi service info; contact dealer for confirmed software/TSB.
  8. After repair or replacement, clear codes, perform drive cycle or forced readiness, and confirm code does not return. Verify proper sensor switching and heater operation with live data.
  9. If intermittent, wiggle-test harness, inspect for chafing, and consider securing wiring; use smoke test to detect exhaust leaks that could influence sensor behavior.

Likely causes

  • Failed oxygen sensor heater (most common)
  • Damaged sensor connector (corrosion or water intrusion)
  • Broken or shorted heater supply/ground wire between sensor and PCM
  • Blown fuse or faulty fuse link for heater circuit
  • PCM heater driver failure (less common)

Fault status

⚠️ Status
P0135 — Oxygen Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction. Heater circuit failed to operate within expected parameters; sensor may not reach operating temperature.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5 - 2.0 hours

Similar codes

P0141 P0155 P0130 P0131 P0132 P0133
9,601

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Code

P0135

GWM P — Powertrain

- Heated oxygen sensor circuit fault (bank 1, sensor 1)

Brand: GWM
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed O2 sensor heater element
  • Open or shorted heater circuit wiring (power or ground)
  • Blown fuse or faulty relay supplying heater circuit
  • Corroded/poor connector or pin contact at sensor or harness
  • PCM driver fault or internal short
  • Aftermarket or incorrect sensor installed

Symptoms

  • Check Engine Light (MIL) illuminated with P0135 stored
  • Heater-related readiness monitor incomplete or in fault
  • Long cold start enrichment / poor emissions until engine warms up
  • Lower fuel economy or rough idle until sensor warms
  • Elevated tailpipe emissions (failed emissions test)
  • Possible intermittent MIL if wiring or connector is intermittent

What to check

  • Retrieve freeze frame and live data with a diagnostic scan tool (confirm Bank 1 Sensor 1 identification)
  • Verify vehicle-specific code is P0135 (heater circuit) and check readiness status
  • Visually inspect sensor, wiring, and connector for damage, corrosion, melted insulation, or exhaust soot
  • Check fuses and relays related to O2 sensor heaters
  • Backprobe heater power and ground pins with ignition ON (engine off) to confirm supply voltage and control ground per factory wiring diagrams
  • Measure heater resistance at sensor with connector disconnected and compare to specification

Signal parameters

  • Heater resistance (cold): typically 2–20 ohms depending on sensor; consult Audi spec
  • Heater supply voltage: battery voltage (approx. 12 V) with ignition ON (engine off)
  • Heater control: PCM provides ground switching or a fused supply feed — verify switching behavior with scope or DVOM
  • O2 sensor voltage (post-heater warmup): switching ~0.1–0.9 V in rich/lean cycles for narrowband sensors
  • Heater current draw: expected few hundred mA; abnormally high indicates short, open indicates open circuit

Diagnostic algorithm

  1. Connect a scan tool, confirm P0135 and identify Bank 1 Sensor 1. Record freeze frame and readiness status.
  2. Perform a visual inspection of the sensor, connector, and wiring harness for damage, corrosion, rodent chew, or heat damage.
  3. With ignition OFF, disconnect sensor connector. Measure heater element resistance across heater pins; compare to Audi spec. If within spec, proceed; if open/infinite or shorted, replace sensor.
  4. With connector disconnected and ignition ON (engine off), measure heater supply voltage at harness pin. If no supply, check related fuses/relays and wiring back to power source.
  5. With connector disconnected, backprobe heater ground/control pin and monitor while cranking or with engine running if required per OEM procedure; verify PCM provides ground switching (or supply) as specified.
  6. If supply and control are present but heater resistance out of range, replace sensor. If heater resistance is correct but no switching/ground from PCM, inspect wiring for opens/shorts and repair. Check for shorts to battery or ground.
  7. If wiring and connectors are good but PCM does not command the heater, check for relevant fuse/relay and then consider PCM output testing or software update per Audi service info; contact dealer for confirmed software/TSB.
  8. After repair or replacement, clear codes, perform drive cycle or forced readiness, and confirm code does not return. Verify proper sensor switching and heater operation with live data.
  9. If intermittent, wiggle-test harness, inspect for chafing, and consider securing wiring; use smoke test to detect exhaust leaks that could influence sensor behavior.

Likely causes

  • Failed oxygen sensor heater (most common)
  • Damaged sensor connector (corrosion or water intrusion)
  • Broken or shorted heater supply/ground wire between sensor and PCM
  • Blown fuse or faulty fuse link for heater circuit
  • PCM heater driver failure (less common)

Fault status

⚠️ Status
P0135 — Oxygen Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction. Heater circuit failed to operate within expected parameters; sensor may not reach operating temperature.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5 - 2.0 hours

Similar codes

P0141 P0155 P0130 P0131 P0132 P0133
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Code

P0135

HUMMER P — Powertrain

Heated Oxygen Sensor (HO2S) Heater Performance Bank 1 Sensor 1

Brand: HUMMER
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed O2 sensor heater element
  • Open or shorted heater circuit wiring (power or ground)
  • Blown fuse or faulty relay supplying heater circuit
  • Corroded/poor connector or pin contact at sensor or harness
  • PCM driver fault or internal short
  • Aftermarket or incorrect sensor installed

Symptoms

  • Check Engine Light (MIL) illuminated with P0135 stored
  • Heater-related readiness monitor incomplete or in fault
  • Long cold start enrichment / poor emissions until engine warms up
  • Lower fuel economy or rough idle until sensor warms
  • Elevated tailpipe emissions (failed emissions test)
  • Possible intermittent MIL if wiring or connector is intermittent

What to check

  • Retrieve freeze frame and live data with a diagnostic scan tool (confirm Bank 1 Sensor 1 identification)
  • Verify vehicle-specific code is P0135 (heater circuit) and check readiness status
  • Visually inspect sensor, wiring, and connector for damage, corrosion, melted insulation, or exhaust soot
  • Check fuses and relays related to O2 sensor heaters
  • Backprobe heater power and ground pins with ignition ON (engine off) to confirm supply voltage and control ground per factory wiring diagrams
  • Measure heater resistance at sensor with connector disconnected and compare to specification

Signal parameters

  • Heater resistance (cold): typically 2–20 ohms depending on sensor; consult Audi spec
  • Heater supply voltage: battery voltage (approx. 12 V) with ignition ON (engine off)
  • Heater control: PCM provides ground switching or a fused supply feed — verify switching behavior with scope or DVOM
  • O2 sensor voltage (post-heater warmup): switching ~0.1–0.9 V in rich/lean cycles for narrowband sensors
  • Heater current draw: expected few hundred mA; abnormally high indicates short, open indicates open circuit

Diagnostic algorithm

  1. Connect a scan tool, confirm P0135 and identify Bank 1 Sensor 1. Record freeze frame and readiness status.
  2. Perform a visual inspection of the sensor, connector, and wiring harness for damage, corrosion, rodent chew, or heat damage.
  3. With ignition OFF, disconnect sensor connector. Measure heater element resistance across heater pins; compare to Audi spec. If within spec, proceed; if open/infinite or shorted, replace sensor.
  4. With connector disconnected and ignition ON (engine off), measure heater supply voltage at harness pin. If no supply, check related fuses/relays and wiring back to power source.
  5. With connector disconnected, backprobe heater ground/control pin and monitor while cranking or with engine running if required per OEM procedure; verify PCM provides ground switching (or supply) as specified.
  6. If supply and control are present but heater resistance out of range, replace sensor. If heater resistance is correct but no switching/ground from PCM, inspect wiring for opens/shorts and repair. Check for shorts to battery or ground.
  7. If wiring and connectors are good but PCM does not command the heater, check for relevant fuse/relay and then consider PCM output testing or software update per Audi service info; contact dealer for confirmed software/TSB.
  8. After repair or replacement, clear codes, perform drive cycle or forced readiness, and confirm code does not return. Verify proper sensor switching and heater operation with live data.
  9. If intermittent, wiggle-test harness, inspect for chafing, and consider securing wiring; use smoke test to detect exhaust leaks that could influence sensor behavior.

Likely causes

  • Failed oxygen sensor heater (most common)
  • Damaged sensor connector (corrosion or water intrusion)
  • Broken or shorted heater supply/ground wire between sensor and PCM
  • Blown fuse or faulty fuse link for heater circuit
  • PCM heater driver failure (less common)

Fault status

⚠️ Status
P0135 — Oxygen Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction. Heater circuit failed to operate within expected parameters; sensor may not reach operating temperature.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5 - 2.0 hours

Similar codes

P0141 P0155 P0130 P0131 P0132 P0133
Repair manuals

Manual library for HUMMER

138

Browse 138 HUMMER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

HUMMER

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Code

P0135

LAND ROVER P — Powertrain

Malfunction of the heater circuit of the sensor (bank 1 sensor 1)

Brand: LAND ROVER
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed O2 sensor heater element
  • Open or shorted heater circuit wiring (power or ground)
  • Blown fuse or faulty relay supplying heater circuit
  • Corroded/poor connector or pin contact at sensor or harness
  • PCM driver fault or internal short
  • Aftermarket or incorrect sensor installed

Symptoms

  • Check Engine Light (MIL) illuminated with P0135 stored
  • Heater-related readiness monitor incomplete or in fault
  • Long cold start enrichment / poor emissions until engine warms up
  • Lower fuel economy or rough idle until sensor warms
  • Elevated tailpipe emissions (failed emissions test)
  • Possible intermittent MIL if wiring or connector is intermittent

What to check

  • Retrieve freeze frame and live data with a diagnostic scan tool (confirm Bank 1 Sensor 1 identification)
  • Verify vehicle-specific code is P0135 (heater circuit) and check readiness status
  • Visually inspect sensor, wiring, and connector for damage, corrosion, melted insulation, or exhaust soot
  • Check fuses and relays related to O2 sensor heaters
  • Backprobe heater power and ground pins with ignition ON (engine off) to confirm supply voltage and control ground per factory wiring diagrams
  • Measure heater resistance at sensor with connector disconnected and compare to specification

Signal parameters

  • Heater resistance (cold): typically 2–20 ohms depending on sensor; consult Audi spec
  • Heater supply voltage: battery voltage (approx. 12 V) with ignition ON (engine off)
  • Heater control: PCM provides ground switching or a fused supply feed — verify switching behavior with scope or DVOM
  • O2 sensor voltage (post-heater warmup): switching ~0.1–0.9 V in rich/lean cycles for narrowband sensors
  • Heater current draw: expected few hundred mA; abnormally high indicates short, open indicates open circuit

Diagnostic algorithm

  1. Connect a scan tool, confirm P0135 and identify Bank 1 Sensor 1. Record freeze frame and readiness status.
  2. Perform a visual inspection of the sensor, connector, and wiring harness for damage, corrosion, rodent chew, or heat damage.
  3. With ignition OFF, disconnect sensor connector. Measure heater element resistance across heater pins; compare to Audi spec. If within spec, proceed; if open/infinite or shorted, replace sensor.
  4. With connector disconnected and ignition ON (engine off), measure heater supply voltage at harness pin. If no supply, check related fuses/relays and wiring back to power source.
  5. With connector disconnected, backprobe heater ground/control pin and monitor while cranking or with engine running if required per OEM procedure; verify PCM provides ground switching (or supply) as specified.
  6. If supply and control are present but heater resistance out of range, replace sensor. If heater resistance is correct but no switching/ground from PCM, inspect wiring for opens/shorts and repair. Check for shorts to battery or ground.
  7. If wiring and connectors are good but PCM does not command the heater, check for relevant fuse/relay and then consider PCM output testing or software update per Audi service info; contact dealer for confirmed software/TSB.
  8. After repair or replacement, clear codes, perform drive cycle or forced readiness, and confirm code does not return. Verify proper sensor switching and heater operation with live data.
  9. If intermittent, wiggle-test harness, inspect for chafing, and consider securing wiring; use smoke test to detect exhaust leaks that could influence sensor behavior.

Likely causes

  • Failed oxygen sensor heater (most common)
  • Damaged sensor connector (corrosion or water intrusion)
  • Broken or shorted heater supply/ground wire between sensor and PCM
  • Blown fuse or faulty fuse link for heater circuit
  • PCM heater driver failure (less common)

Fault status

⚠️ Status
P0135 — Oxygen Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction. Heater circuit failed to operate within expected parameters; sensor may not reach operating temperature.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5 - 2.0 hours

Similar codes

P0141 P0155 P0130 P0131 P0132 P0133
350

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Code

P0135

MITSUBISHI P — Powertrain

Oxygen sensor(front) heater

Brand: MITSUBISHI
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed O2 sensor heater element
  • Open or shorted heater circuit wiring (power or ground)
  • Blown fuse or faulty relay supplying heater circuit
  • Corroded/poor connector or pin contact at sensor or harness
  • PCM driver fault or internal short
  • Aftermarket or incorrect sensor installed

Symptoms

  • Check Engine Light (MIL) illuminated with P0135 stored
  • Heater-related readiness monitor incomplete or in fault
  • Long cold start enrichment / poor emissions until engine warms up
  • Lower fuel economy or rough idle until sensor warms
  • Elevated tailpipe emissions (failed emissions test)
  • Possible intermittent MIL if wiring or connector is intermittent

What to check

  • Retrieve freeze frame and live data with a diagnostic scan tool (confirm Bank 1 Sensor 1 identification)
  • Verify vehicle-specific code is P0135 (heater circuit) and check readiness status
  • Visually inspect sensor, wiring, and connector for damage, corrosion, melted insulation, or exhaust soot
  • Check fuses and relays related to O2 sensor heaters
  • Backprobe heater power and ground pins with ignition ON (engine off) to confirm supply voltage and control ground per factory wiring diagrams
  • Measure heater resistance at sensor with connector disconnected and compare to specification

Signal parameters

  • Heater resistance (cold): typically 2–20 ohms depending on sensor; consult Audi spec
  • Heater supply voltage: battery voltage (approx. 12 V) with ignition ON (engine off)
  • Heater control: PCM provides ground switching or a fused supply feed — verify switching behavior with scope or DVOM
  • O2 sensor voltage (post-heater warmup): switching ~0.1–0.9 V in rich/lean cycles for narrowband sensors
  • Heater current draw: expected few hundred mA; abnormally high indicates short, open indicates open circuit

Diagnostic algorithm

  1. Connect a scan tool, confirm P0135 and identify Bank 1 Sensor 1. Record freeze frame and readiness status.
  2. Perform a visual inspection of the sensor, connector, and wiring harness for damage, corrosion, rodent chew, or heat damage.
  3. With ignition OFF, disconnect sensor connector. Measure heater element resistance across heater pins; compare to Audi spec. If within spec, proceed; if open/infinite or shorted, replace sensor.
  4. With connector disconnected and ignition ON (engine off), measure heater supply voltage at harness pin. If no supply, check related fuses/relays and wiring back to power source.
  5. With connector disconnected, backprobe heater ground/control pin and monitor while cranking or with engine running if required per OEM procedure; verify PCM provides ground switching (or supply) as specified.
  6. If supply and control are present but heater resistance out of range, replace sensor. If heater resistance is correct but no switching/ground from PCM, inspect wiring for opens/shorts and repair. Check for shorts to battery or ground.
  7. If wiring and connectors are good but PCM does not command the heater, check for relevant fuse/relay and then consider PCM output testing or software update per Audi service info; contact dealer for confirmed software/TSB.
  8. After repair or replacement, clear codes, perform drive cycle or forced readiness, and confirm code does not return. Verify proper sensor switching and heater operation with live data.
  9. If intermittent, wiggle-test harness, inspect for chafing, and consider securing wiring; use smoke test to detect exhaust leaks that could influence sensor behavior.

Likely causes

  • Failed oxygen sensor heater (most common)
  • Damaged sensor connector (corrosion or water intrusion)
  • Broken or shorted heater supply/ground wire between sensor and PCM
  • Blown fuse or faulty fuse link for heater circuit
  • PCM heater driver failure (less common)

Fault status

⚠️ Status
P0135 — Oxygen Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction. Heater circuit failed to operate within expected parameters; sensor may not reach operating temperature.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5 - 2.0 hours

Similar codes

P0141 P0155 P0130 P0131 P0132 P0133
406

Browse 406 MITSUBISHI manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

MITSUBISHI

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