P0106 on 2016-2022 Honda HR-V: MAP Sensor Causes and Fixes

What's Unique About the 2016-2022 Honda HR-V

For the 2016-2022 HR-V with the 1.8L R18 engine, the P0106 code is a straightforward diagnostic issue with no unique platform-specific quirks or widespread defects noted in technical service bulletins. The problem is almost always what it appears to be: a sensor performance issue. The MAP sensor (OEM part 37830-RNA-A01) is a common component across many Honda models from this era, making diagnosis and parts sourcing relatively simple. A notable characteristic for this platform is the potential for the code to be triggered after disconnecting the battery or cleaning the throttle body, which can often be resolved with an idle relearn procedure rather than part replacement.

Symptoms You May Notice

• Check Engine Light is on
• Rough or unstable idle
• Hesitation or stumbling during acceleration
• Noticeably reduced fuel economy
• Black smoke from the exhaust in some cases
• Difficulty starting the engine
• Engine may stall at low speeds or when stopping
• In some cases, the engine may enter a reduced-power 'limp mode'

Most Likely Causes

1. Faulty Manifold Absolute Pressure (MAP) Sensor 🔴 High Probability → Shop Manifold Absolute Pressure Sensor The MAP sensor is a sensitive electronic component that can fail over time due to heat cycles, internal wear, or contamination from oil and carbon.
   How to confirm: With the key on and engine off, use a scan tool to compare the MAP sensor reading with the Barometric Pressure (BARO) reading. They should be nearly identical. If they differ significantly, or if the voltage does not change smoothly when revving the engine, the sensor is likely faulty. Some users attempt to clean the sensor with an approved electrical cleaner as a first step, but replacement is often necessary.
   Typical fix: Replace the MAP sensor. It is typically held in place by a single bolt on the intake manifold.
   Est. part cost: $25-$100
2. Vacuum Leak 🟡 Medium Probability Rubber vacuum hoses, the air intake boot, and intake gaskets can become brittle and crack over time, creating unmetered air leaks that confuse the MAP sensor.
   How to confirm: Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnection. Pay close attention to the PCV hose and brake booster line. The most effective method is to perform a smoke test, which will force smoke through the intake system and reveal the source of any leaks.
   Typical fix: Replace the cracked hose or faulty gasket.
   Est. part cost: $10-$50
3. Damaged Wiring or Connector ⚪ Low Probability Engine bay heat and vibration can, over many years, cause wiring to become brittle or pins in the connector to become loose, corroded, or lose tension.
   How to confirm: Visually inspect the MAP sensor's electrical connector and wiring harness for any signs of damage, corrosion, or loose pins. Ensure the connector is fully seated. Use a multimeter to check for the correct reference voltage (usually 5V), a good ground, and a smooth signal voltage change at the connector.
   Typical fix: Repair the damaged wiring or replace the pigtail connector.
   Est. part cost: $15-$40

Rare But Worth Checking

• Dirty or Uncalibrated Throttle Body: → Shop Fuel Injection Throttle Body Excessive carbon buildup on the throttle plate can restrict airflow at idle, causing erratic MAP readings. Furthermore, cleaning the throttle body or disconnecting the battery without performing an 'Idle Relearn Procedure' can cause the ECM to set a P0106 code because it has lost its learned idle values.
• Severely Clogged Engine Air Filter: A completely blocked air filter can starve the engine of air, causing an abnormally high vacuum reading that the ECM may interpret as a MAP sensor performance issue.
• Internal Engine Mechanical Issue: Extremely rare for this code, but a significant internal issue like a stuck or burnt valve can affect manifold pressure enough to trigger a P0106 code after other causes are ruled out.
• Faulty Powertrain Control Module (PCM): This is extremely rare. The PCM itself can fail, but this should only be considered after all other possible causes have been exhaustively ruled out by a professional.

Diagnosis Steps

1. Read all fault codes with an OBD-II scanner. Note any other codes that are present.
2. Visually inspect the air intake tube between the air filter and the throttle body for any cracks or loose connections.
3. Inspect all vacuum hoses connected to the intake manifold for obvious cracks, breaks, or disconnections.
4. Inspect the MAP sensor's electrical connector for corrosion, damage, or loose pins. Ensure it is seated firmly.
5. With the key on and engine off, use a scan tool to view live data. Compare the 'MAP' reading to the 'BARO' (Barometric Pressure) reading. They should be very close. If not, the sensor is suspect.
6. Start the engine and observe the MAP sensor reading at idle. It should be a steady, low voltage/pressure reading. Briefly rev the engine; the reading should change instantly and smoothly.
7. Inspect the throttle body for heavy carbon buildup. If cleaning is performed or the battery has been disconnected, perform an 'Idle Relearn Procedure'.
8. If a vacuum leak is suspected but not visible, perform a smoke test to pinpoint the source of the leak.
9. If no vacuum leaks are found and the wiring appears intact, the MAP sensor is the most likely cause of the problem.

Parts You'll Likely Need

• Manifold Absolute Pressure (MAP) Sensor (OEM #37830-RNA-A01) — This is the most common failure point for code P0106. It is a critical sensor that wears out over time.
  Trusted brands: Honda (Genuine OEM), Denso (Often the OEM supplier), Bosch, NTK/NGK
  OEM price range: $70-$100
  Aftermarket price range: $25-$60

Related Codes That Often Appear With This One

• P0107 — This code indicates 'MAP Sensor Circuit Low Input,' which can be triggered by the same faulty sensor or wiring issue causing the P0106 performance code.
• P0108 — This code indicates 'MAP Sensor Circuit High Input,' which points to the same set of potential failures as P0106 and P0107.

Technical Service Bulletins (TSBs) & Recalls

• No specific Honda Technical Service Bulletins (TSBs) for P0106 on the 2016-2022 HR-V are widely available in public databases. However, TSBs from other manufacturers (e.g., GM Service Bulletin 20-NA-193) note that similar codes can be set by environmental factors like ice forming on the MAP sensor in freezing temperatures, which is a rare but plausible scenario.

Platform-Specific Known Issues

• Throttle Body Idle Relearn Requirement: → Shop Fuel Injection Throttle Body A recurring theme among Honda owners is the appearance of code P0106 immediately following a battery replacement, battery disconnection, or after cleaning the throttle body. This occurs because the ECM's memory of the learned idle position is wiped. The new, cleaner throttle body position doesn't match the old stored values, leading to an air/fuel calculation error that triggers P0106. The fix is often not a new part, but performing the specific 'Idle Relearn Procedure' for the vehicle.

Mechanic-Grade Diagnostic Values

• MAP Sensor Reference Voltage — expected: ~5.0V. Failure: No voltage or significantly lower voltage indicates a problem with the PCM or wiring.
• MAP Sensor Signal Voltage (Key On, Engine Off) — expected: ~3.0V - 3.5V. Failure: A reading significantly outside this range, such as ~0.37V as noted in one forum, points to a sensor or wiring issue. A reading below 0.23V can trigger a P0107 (low voltage) code.
• MAP Sensor Signal Voltage (Engine at Idle) — expected: ~1.0V or less. Failure: Voltage that doesn't drop from the KOEO reading, or is unstable, indicates a faulty sensor or a vacuum leak.
• Live Data: MAP Reading at Idle — expected: 15-25 kPa. Failure: A reading that fluctuates wildly or stays at 0 kPa suggests the sensor has failed.

Scan Tool Commands That Help

• Honda Diagnostic System (HDS): MAP Sensor Voltage Check (Live Data) — Used as the primary step to confirm if the MAP sensor voltage is out of the expected range. For a related code (P0107), the HDS is used to check if the voltage is below the 0.23V threshold with the key on, engine off.
• Honda Diagnostic System (HDS): Jump SCS Line — This service function is used to prepare the vehicle for continuity checks on the MAP sensor wiring to the PCM.

Wiring & Ground Locations

• MAP Sensor Connector (3-Pin) — On the intake manifold, held by a single bolt.. This is the primary connection point for the sensor. Pins must be clean and secure. Pin 1 is typically the signal, Pin 2 is the ground, and Pin 3 is the 5V reference.
• PCM Connector B (51-Pin) — At the Powertrain Control Module (PCM).. Pin B41 is the VCC1 (5V reference) wire for the MAP sensor. Continuity must be checked between this pin and Pin 3 at the sensor connector if reference voltage is missing.
• G101 — Commonly found on or near the engine block or cylinder head.. A wiring diagram for the R18 engine family shows G101 as a primary engine ground. A loose or corroded G101 can cause erratic sensor readings, including for the MAP sensor.

Real Owner Repair Stories

• Reddit r/MechanicAdvice (Hyundai (symptoms and cause are directly applicable to the Honda issue)) — Check Engine Light with P0106, incredibly hard idling, and stalling.
  ❌ Tried (didn't work) Replacing the MAP sensor., Clearing the DTC code (it returned).
  ✅ What actually fixed it The issue started after the battery died. The user noted the car seemed to have relearned its idle, but the code persisted. The proposed next step, which aligns with Honda-specific issues, was to clean the throttle body and perform a full idle relearn procedure.

OEM Part Supersession History

• 37830-RNA-A01 → 37830-RNA-A01 — No supersession found.
  Heads up: This part number remains consistent across many Honda models and years, including the 2016-2022 HR-V.

Model Year Variations Within This Range

• 2019-2022: The HR-V received a facelift for the 2019 model year. While the 1.8L R18Z9 engine remained the standard powertrain in North America, the exterior styling, headlights, and interior features like the Display Audio system were updated. The 6-speed manual transmission was discontinued. These changes do not directly affect the diagnosis of P0106, as the core engine management components, including the MAP sensor, remained the same.

Diagnostic Flowchart

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0107 — MAP Sensor Circuit Low Voltage. Directly related to the MAP sensor electrical connector and wiring harness damage or corrosion mentioned as a common cause for MAP sensor failures.
• P0108 — MAP Sensor Circuit High Voltage. Also related to the MAP sensor wiring issues, such as a short circuit or a completely failed sensor providing an out-of-bounds high reading.
• P0171 — System Too Lean (Bank 1). Often appears alongside P0106 if the root cause is a vacuum leak (cracked hoses, intake boot, or gaskets) allowing unmetered air into the engine.
• P0507 — Idle Control System RPM Higher Than Expected. Can trigger alongside P0106 after cleaning the throttle body or disconnecting the battery if the ECM's learned idle position is wiped and the Idle Relearn Procedure is not performed.

Frequently Asked Questions