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P2138LexusLexus NX HubAll Lexus P2138Critical Severity

P2138 on Lexus NX: Fix & DLC Location

Factory diagnostic troubleshooting wire for fault code P2138 (P2138: Throttle/Pedal Position Sensor/Switch D / E Voltage Correlation) specifically on the Lexus NX (2022–2026, 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP)).

Lexus NX
DIY Parts Estimate
$180 - $480 (DIY: $50 - $140)
NX OEM Fitment
Shop Labor Quote
$180 – $380
Based on $135/hr labor
Drivability Status
Not Recommended
Critical urgency level
Est. DIY Time
45 – 90 Min
Basic hand tools
Check P2138 On Another Lexus Model:
Lexus ESLexus RXLexus NXLexus GXLexus LXLexus IS

1. Symptoms of P2138 on Lexus NX

When the Engine Control Module (ECM/PCM) on your Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP)) logs fault code P2138, drivers commonly observe:

System alert or indicator light illuminated (P2138) on Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP))
Intermittent performance throttling or unexpected operation halts on Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP))
Audible sensor relay clicking or anomalous status telemetry in dashboard logs on Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP))
Degraded operational throughput or error dialog popups on startup on Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP))
Readiness monitors failing state emissions or system compliance audits on Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP))
Lexus NX OBD-II Port Location
The 16-pin diagnostic connector is located Under driver dash near footwell illumination lamp. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Lexus NX

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

55%
Component aging, oxidation, or degraded internal circuit element (Gas Pedal Position Sensor Assembly) (Lexus OEM Part)
25%
Wiring harness abrasion, loose terminal pin, or ground voltage float (Lexus OEM Part)
12%
Outdated firmware microcode or incompatible software driver update (Lexus OEM Part)
8%
Thermal stress or excessive operational duty-cycle fatigue (Lexus OEM Part)
8%
Contamination from carbon buildup, moisture ingress, or dirty filtration (Lexus OEM Part)

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

01
Connect Diagnostic Scanner / Logging Monitor to Retrieve Telemetry

Interface with the diagnostic port or system console using verified scanning hardware. Record freeze-frame data, active sub-codes, and timestamps to isolate whether P2138 is static or intermittent. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).

Required Tool: 10mm socket, Pedal assembly
02
Perform Physical & Electrical Circuit Inspection

Visually inspect the physical component (Gas Pedal Position Sensor Assembly), connector pins, and associated wiring harnesses for signs of corrosion, thermal melting, or loose grounding clips. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).

Required Tool: Multimeter, Flashlight, Contact Cleaner Spray
03
Component Testing & Resistance / Voltage Verification

Measure reference voltages and resistance thresholds against manufacturer factory specifications. Replace any component failing nominal impedance tolerances. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).

Required Tool: 10mm socket, Pedal assembly
04
Execute Component Replacement or Software Configuration Patch

Install genuine OEM replacement hardware or execute registry / service commands. Ensure all mounting bolts are torqued to factory specifications. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).

Required Tool: Standard Hand Tool Set / Terminal Commands
05
Clear Diagnostic Trouble Code & Complete Verification Drive Cycle

Erase the fault code from non-volatile memory. Perform a standard verification cycle (e.g. 15-minute mixed drive or system stress benchmark) to ensure monitors reset to 'Ready' state without recurrent fault flags. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).

Required Tool: OBD-II Code Reader / Diagnostic Suite

Other Common Fault Codes on Lexus NX

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

4. Lexus NX P2138 FAQs

What causes code P2138 to trigger on a Lexus NX?

On the Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP)), P2138 is most frequently caused by Component aging, oxidation, or degraded internal circuit element (Gas Pedal Position Sensor Assembly) or Wiring harness abrasion, loose terminal pin, or ground voltage float.

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

On the Lexus NX, the 16-pin DLC diagnostic connector is located Under driver dash near footwell illumination lamp. 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 NX with code P2138?

No. Immediate shutdown / repair required to prevent permanent hardware destruction or total system lockup. Given that P2138 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.