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P0112LexusLexus RX HubAll Lexus P0112Medium Severity

P0112 on Lexus RX

Intake Air Temperature Sensor 1 Circuit Low Input

Factory diagnostic protocol and troubleshooting wire for fault code P0112 specifically for the Lexus RX (2020–2026, 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP)).

Verified OEM Telemetry & Field Repair Tree
Lexus RX2020–2026
Lexus RX
SUV2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
RX SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Drivable (Short Trip)
Medium urgency level
Est. Repair Cost
$80 - $220
Parts & Labor DIY
Check P0112 On Another Lexus Model:
Diagnose P0112 on Specific RX Model Year:

1. Symptoms of P0112 on Lexus RX

When the Engine Control Module (ECM/PCM) on your Lexus RX (2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP)) logs fault code P0112, drivers commonly observe:

Check Engine Light on on Lexus RX (2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP))
Lean engine stumble on cold start on Lexus RX (2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP))
Poor fuel economy on Lexus RX (2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP))
Lexus RX OBD-II Port Location
The 16-pin diagnostic connector is located Driver footwell above brake pedal assembly. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Lexus RX

Historical warranty claims and technical repair bulletins for Lexus RX point to the following failure distribution:

55%
IAT sensor shorted to ground (Lexus OEM Part)
25%
Damaged wiring harness (Lexus OEM Part)
12%
Faulty MAF/IAT integrated sensor (Lexus OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Lexus RX.

3. Step-by-Step DIY Repair Guide for Lexus RX

01
Scan and Record Freeze Frame Telemetry

Connect an OBD-II scan tool and record freeze frame sensor telemetry for code P0112 to note engine RPM, load, and voltage when the fault triggered. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).

Required Tool: OBD-II Scanner
02
Inspect Related Wiring Harness & Connectors

Inspect the electrical connector and wiring harness related to P0112 for chafing, corrosion, moisture, or pin push-out. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).

Required Tool: Flashlight, Multimeter
03
Test Component Resistance & Voltage Supply

Measure circuit voltage supply (12V B+ or 5V reference) and sensor/actuator resistance according to factory repair manual specifications. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).

Required Tool: Digital Multimeter
04
Replace Defective Component

Install a new OEM-grade replacement part, torque fasteners to factory spec, and ensure electrical locking tabs click firmly. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).

Required Tool: Hand Tool Socket Set, Torque Wrench
05
Clear Trouble Codes & Complete Drive Cycle

Clear all stored DTCs from vehicle memory and perform an OBD-II drive cycle to confirm the diagnostic monitor resets to 'Ready'. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Lexus RX (P0112)

Prime Fast Delivery & Verified Fitment
Variable Valve Timing (VVT)

VVT Oil Control Solenoid Valve

4.6 / 5.0 (Direct Fit)

Restores accurate camshaft timing and oil pressure regulation on Lexus RX.

$34 – $65 Prime
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Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Lexus RXVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Lexus RX

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Lexus RX:

4. Lexus RX P0112 FAQs

What causes code P0112 to trigger on a Lexus RX?

On the Lexus RX (2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP)), P0112 is most frequently caused by IAT sensor shorted to ground or Damaged wiring harness.

Where is the OBD-II port located on my Lexus RX?

On the Lexus RX, the 16-pin DLC diagnostic connector is located Driver footwell above brake pedal assembly. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Lexus RX with code P0112?

Yes. ECM assumes intake air is 280°F+. Given that P0112 carries a Medium severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.