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Home / DTC / P2037 — Reductant Injection Air Pressure Sensor A Circuit

P2037 — Reductant Injection Air Pressure Sensor A Circuit

Detailed page for trouble code P2037.

34,332codes
59brands
11,841generic
22,491specific
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Code

P2037

Generic P — Powertrain

Reductant Injection Air Pressure Sensor A Circuit

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

Causes

  • Open circuit or short (to ground or battery) in sensor wiring
  • Corroded, loose, or damaged sensor connector
  • Failed reductant injection air pressure sensor
  • Poor ground or high-resistance return
  • Water intrusion or physical damage to harness or sensor
  • Faulty ECM or control module (rare)

Symptoms

  • Malfunction indicator lamp (MIL) / Check Engine light ON
  • Stored P2037 and possibly related SCR/reductant system codes
  • Reduced or inhibited reductant dosing, SCR reduced functionality
  • Possible increased NOx emissions or failed emissions test
  • In some vehicles, engine derate or limp mode if related faults present

What to check

  • Read and record freeze-frame and related codes with a scan tool
  • Visual inspection of sensor, connector, and wiring for damage, corrosion, or contamination
  • Wiggle test wiring and connector while watching live sensor data
  • Backprobe sensor connector to verify reference, signal and ground voltages
  • Check continuity and resistance of wires between sensor and ECM
  • Inspect grounds and power fuses for the reductant/SCR system

Signal parameters

  • Reference voltage: typically 5 V (check vehicle-specific spec)
  • Signal output: typically ~0.5 V (low pressure) to ~4.5 V (high pressure) — varies by manufacturer
  • Ground: near 0 V; chassis/ECM ground continuity should be low (
  • Open-circuit: signal may float to 0 V or reference voltage; short-to-ground: ~0 V; short-to-battery: ~reference or > supply
  • If sensor is resistive type, resistance should be within manufacturer range (consult spec)

Diagnostic algorithm

  1. Verify code P2037 with a scan tool, save freeze-frame data and any related codes. Attempt to clear the code and see if it returns.
  2. Visually inspect the reductant injection air pressure sensor, its connector and harness for corrosion, water ingress, damage, chafing, or loose pins. Repair obvious damage.
  3. With key ON (engine OFF), backprobe the sensor connector and confirm: a stable reference voltage (usually ~5 V), a good ground (near 0 V), and the sensor signal voltage. Compare to expected ranges for ambient conditions.
  4. Wiggle the wiring and connector while monitoring live signal. Intermittent changes indicate a wiring/connector fault.
  5. Check continuity between the sensor ground and engine/ECM ground. Measure resistance between sensor power and ECM reference terminal. Repair high-resistance circuits.
  6. If the signal is shorted or open, isolate by disconnecting the sensor and measuring for short to ground or battery on the harness conductor. Repair wiring as required.
  7. If wiring and connectors test good but the sensor signal is out of range or not changing with pressure, replace the sensor and retest.
  8. After repair or replacement, clear codes and perform functional tests: monitor live data during an SCR/reductant system commanded event or vehicle drive cycle to confirm proper operation.
  9. If code persists after sensor and wiring repairs, test or replace the ECM only after confirming wiring and power/ground integrity and consulting manufacturer procedures.

Likely causes

  • Damaged/chafed wiring between sensor and ECM
  • Contaminated or corroded connector at sensor
  • Sensor internal failure
  • High-resistance/poor ground at sensor mounting or harness
  • Intermittent connection due to vibration or debris

Fault status

⚠️ Status
Electrical fault detected in Reductant Injection Air Pressure Sensor A circuit (open/short/intermittent). Reductant dosing may be disabled or limited until repaired.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-2.0 hours

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Code

P2037

LAND ROVER P — Powertrain

Circuit of the air pressure sensor with injection reduced

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

Causes

  • Open circuit or short (to ground or battery) in sensor wiring
  • Corroded, loose, or damaged sensor connector
  • Failed reductant injection air pressure sensor
  • Poor ground or high-resistance return
  • Water intrusion or physical damage to harness or sensor
  • Faulty ECM or control module (rare)

Symptoms

  • Malfunction indicator lamp (MIL) / Check Engine light ON
  • Stored P2037 and possibly related SCR/reductant system codes
  • Reduced or inhibited reductant dosing, SCR reduced functionality
  • Possible increased NOx emissions or failed emissions test
  • In some vehicles, engine derate or limp mode if related faults present

What to check

  • Read and record freeze-frame and related codes with a scan tool
  • Visual inspection of sensor, connector, and wiring for damage, corrosion, or contamination
  • Wiggle test wiring and connector while watching live sensor data
  • Backprobe sensor connector to verify reference, signal and ground voltages
  • Check continuity and resistance of wires between sensor and ECM
  • Inspect grounds and power fuses for the reductant/SCR system

Signal parameters

  • Reference voltage: typically 5 V (check vehicle-specific spec)
  • Signal output: typically ~0.5 V (low pressure) to ~4.5 V (high pressure) — varies by manufacturer
  • Ground: near 0 V; chassis/ECM ground continuity should be low (
  • Open-circuit: signal may float to 0 V or reference voltage; short-to-ground: ~0 V; short-to-battery: ~reference or > supply
  • If sensor is resistive type, resistance should be within manufacturer range (consult spec)

Diagnostic algorithm

  1. Verify code P2037 with a scan tool, save freeze-frame data and any related codes. Attempt to clear the code and see if it returns.
  2. Visually inspect the reductant injection air pressure sensor, its connector and harness for corrosion, water ingress, damage, chafing, or loose pins. Repair obvious damage.
  3. With key ON (engine OFF), backprobe the sensor connector and confirm: a stable reference voltage (usually ~5 V), a good ground (near 0 V), and the sensor signal voltage. Compare to expected ranges for ambient conditions.
  4. Wiggle the wiring and connector while monitoring live signal. Intermittent changes indicate a wiring/connector fault.
  5. Check continuity between the sensor ground and engine/ECM ground. Measure resistance between sensor power and ECM reference terminal. Repair high-resistance circuits.
  6. If the signal is shorted or open, isolate by disconnecting the sensor and measuring for short to ground or battery on the harness conductor. Repair wiring as required.
  7. If wiring and connectors test good but the sensor signal is out of range or not changing with pressure, replace the sensor and retest.
  8. After repair or replacement, clear codes and perform functional tests: monitor live data during an SCR/reductant system commanded event or vehicle drive cycle to confirm proper operation.
  9. If code persists after sensor and wiring repairs, test or replace the ECM only after confirming wiring and power/ground integrity and consulting manufacturer procedures.

Likely causes

  • Damaged/chafed wiring between sensor and ECM
  • Contaminated or corroded connector at sensor
  • Sensor internal failure
  • High-resistance/poor ground at sensor mounting or harness
  • Intermittent connection due to vibration or debris

Fault status

⚠️ Status
Electrical fault detected in Reductant Injection Air Pressure Sensor A circuit (open/short/intermittent). Reductant dosing may be disabled or limited until repaired.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-2.0 hours

Similar codes

P2036 P2038 P2040 P20E8 P2008
320

Browse 320 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

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