Toggle Side Panel

Shopping Cart

No products in the basket.

Shopping Cart

No products in the basket.

Close search
Home / DTC / P2231 — O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 1

P2231 — O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 1

Detailed page for trouble code P2231.

34,405codes
59brands
11,914generic
22,491specific
All codes P-codes (Powertrain) B-codes (Body) C-codes (Chassis) U-codes (Network/User) Tesla Alerts
Reset
Code

P2231

Generic P — Powertrain

O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 1

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

Causes

  • Damaged wiring or chafed harness causing signal wire to contact heater power/return
  • Corroded or contaminated sensor connector (pins bridged)
  • Internal short within the O2 sensor between heater element and signal element
  • Incorrect or damaged replacement sensor or aftermarket harness miswired
  • PCM/ECM driver or ground fault (rare)

Symptoms

  • Check Engine Light (MIL) illuminated
  • Poor fuel economy and/or drivability issues (hesitation, rough idle)
  • Failed emissions/vehicle may run rich or lean due to incorrect O2 feedback
  • Possible stored related fuel-trim or oxygen sensor codes
  • Heater circuit-related codes may also be present

What to check

  • Scan for additional codes (heater circuit codes, fuel trim, other O2 codes)
  • Visual inspection of Bank 1 Sensor 1 wiring and connector for damage, corrosion, contamination
  • Backprobe sensor connector and PCM pins to compare voltages and signals
  • Measure continuity/resistance between O2 signal and heater pins (should be open)
  • Check heater supply fuse/relay and PCM ground circuits if applicable

Signal parameters

  • O2 sensor (narrowband) signal voltage: ~0.1 V (lean) to ~0.9 V (rich); should switch several times/sec at operating temp
  • Upstream sensor (Sensor 1) should begin switching within 10–60 seconds of warm-up
  • Heater resistance (typical): about 2–20 ohms depending on sensor type — consult vehicle spec
  • Heater supply voltage when commanded: near battery voltage (approx. 12 V) or switched/pulsed by PCM
  • There should be no continuity between the heater circuit and the signal circuit (infinite/open)

Diagnostic algorithm

  1. Retrieve freeze frame and related codes; note conditions when code set (temp, load, rpm).
  2. Perform thorough visual inspection of Bank 1 Sensor 1 harness and connector for damage, melted insulation, fluid intrusion, or aftermarket splices.
  3. With ignition ON (engine off), backprobe connector: verify heater supply/driver voltage and O2 signal reference voltages compared to PCM pin specifications.
  4. Start engine and, once warmed, observe O2 signal voltage at the sensor and at the PCM. Look for abnormal static voltage or heater voltage present on signal line.
  5. With engine off, disconnect sensor and measure resistance between heater pin and signal pin — should read open/infinite. Any continuity indicates internal short or wiring short.
  6. Perform a wiggle test and pin-probe while monitoring to see if movement changes readings (intermittent short).
  7. If wiring and connector checked good and signal/heater are shorted at harness end, suspect failed sensor — replace sensor and retest.
  8. If problem persists with new sensor, trace harness to PCM and check for chafing or other shorts; inspect PCM connector and test PCM driver circuits as last resort.
  9. Clear codes and road test under similar conditions to verify repair.

Likely causes

  • Pin(s) shorted at the sensor connector (pin pushed through, bent, corrosion)
  • Insulation worn where harness rubs against metal, contacting heater feed
  • Failed O2 sensor with internal heater-to-sensor electrical leakage
  • Recent exhaust or engine repair disturbed wiring or sensor connector
  • Connector wet with coolant or oil causing conductive path

Fault status

⚠️ Status
O2 sensor signal circuit has been detected shorted to the heater circuit for Bank 1 Sensor 1. The ECM detected improper voltage or continuity between the sensor signal and heater circuits.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0131 P0132 P0133 P0141 P0031 P0032
9,532

The library contains 9,532 repair and diagnostic manuals. Choose a brand to open the full manual tree by year, model and trim.

ALFA ROMEO
89
AUDI
1,243
BMW
479
CADILLAC
206
CHEVROLET
456
CHRYSLER
193
DAEWOO
75
FIAT
26
GENESIS
207
HUMMER
138
HYUNDAI
371
ISUZU
229
KIA
155
LAND ROVER
280
LEXUS
280
LINCOLN
166
MERCEDES-BENZ
856
MERCURY
296
MITSUBISHI
406
PORSCHE
136
TESLA
58
TOYOTA
2,209
TRIUMPH
131
VOLKSWAGEN
626
VOLVO
221
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P2231

LAND ROVER P — Powertrain

Oxygen sensor signal circuit shorted to ground heater. Bank 1 - sensor 1

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

Causes

  • Damaged wiring or chafed harness causing signal wire to contact heater power/return
  • Corroded or contaminated sensor connector (pins bridged)
  • Internal short within the O2 sensor between heater element and signal element
  • Incorrect or damaged replacement sensor or aftermarket harness miswired
  • PCM/ECM driver or ground fault (rare)

Symptoms

  • Check Engine Light (MIL) illuminated
  • Poor fuel economy and/or drivability issues (hesitation, rough idle)
  • Failed emissions/vehicle may run rich or lean due to incorrect O2 feedback
  • Possible stored related fuel-trim or oxygen sensor codes
  • Heater circuit-related codes may also be present

What to check

  • Scan for additional codes (heater circuit codes, fuel trim, other O2 codes)
  • Visual inspection of Bank 1 Sensor 1 wiring and connector for damage, corrosion, contamination
  • Backprobe sensor connector and PCM pins to compare voltages and signals
  • Measure continuity/resistance between O2 signal and heater pins (should be open)
  • Check heater supply fuse/relay and PCM ground circuits if applicable

Signal parameters

  • O2 sensor (narrowband) signal voltage: ~0.1 V (lean) to ~0.9 V (rich); should switch several times/sec at operating temp
  • Upstream sensor (Sensor 1) should begin switching within 10–60 seconds of warm-up
  • Heater resistance (typical): about 2–20 ohms depending on sensor type — consult vehicle spec
  • Heater supply voltage when commanded: near battery voltage (approx. 12 V) or switched/pulsed by PCM
  • There should be no continuity between the heater circuit and the signal circuit (infinite/open)

Diagnostic algorithm

  1. Retrieve freeze frame and related codes; note conditions when code set (temp, load, rpm).
  2. Perform thorough visual inspection of Bank 1 Sensor 1 harness and connector for damage, melted insulation, fluid intrusion, or aftermarket splices.
  3. With ignition ON (engine off), backprobe connector: verify heater supply/driver voltage and O2 signal reference voltages compared to PCM pin specifications.
  4. Start engine and, once warmed, observe O2 signal voltage at the sensor and at the PCM. Look for abnormal static voltage or heater voltage present on signal line.
  5. With engine off, disconnect sensor and measure resistance between heater pin and signal pin — should read open/infinite. Any continuity indicates internal short or wiring short.
  6. Perform a wiggle test and pin-probe while monitoring to see if movement changes readings (intermittent short).
  7. If wiring and connector checked good and signal/heater are shorted at harness end, suspect failed sensor — replace sensor and retest.
  8. If problem persists with new sensor, trace harness to PCM and check for chafing or other shorts; inspect PCM connector and test PCM driver circuits as last resort.
  9. Clear codes and road test under similar conditions to verify repair.

Likely causes

  • Pin(s) shorted at the sensor connector (pin pushed through, bent, corrosion)
  • Insulation worn where harness rubs against metal, contacting heater feed
  • Failed O2 sensor with internal heater-to-sensor electrical leakage
  • Recent exhaust or engine repair disturbed wiring or sensor connector
  • Connector wet with coolant or oil causing conductive path

Fault status

⚠️ Status
O2 sensor signal circuit has been detected shorted to the heater circuit for Bank 1 Sensor 1. The ECM detected improper voltage or continuity between the sensor signal and heater circuits.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

P0131 P0132 P0133 P0141 P0031 P0032
280

Browse 280 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

Report

Harassment or bullying behavior
Contains mature or sensitive content
Contains misleading or false information
Contains abusive or derogatory content
Contains spam, fake content or potential malware

Block Member?

Please confirm you want to block this member.

You will no longer be able to:

  • See blocked member's posts
  • Mention this member in posts
  • Invite this member to groups
  • Message this member
  • Add this member as a connection

Please note: This action will also remove this member from your connections and send a report to the site admin. Please allow a few minutes for this process to complete.

Report

You have already reported this .