P2138 on Lexus IS: 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 IS (2020–2026, 2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP)).
1. Symptoms of P2138 on Lexus IS
When the Engine Control Module (ECM/PCM) on your Lexus IS (2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP)) logs fault code P2138, drivers commonly observe:
2. Most Likely Causes on Lexus IS
Historical warranty claims and technical repair bulletins for Lexus IS point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Lexus IS
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 IS equipped with 2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP).
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 IS equipped with 2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP).
Measure reference voltages and resistance thresholds against manufacturer factory specifications. Replace any component failing nominal impedance tolerances. on the Lexus IS equipped with 2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP).
Install genuine OEM replacement hardware or execute registry / service commands. Ensure all mounting bolts are torqued to factory specifications. on the Lexus IS equipped with 2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP).
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 IS equipped with 2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP).
Other Common Fault Codes on Lexus IS
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Lexus IS:
4. Lexus IS P2138 FAQs
What causes code P2138 to trigger on a Lexus IS?
On the Lexus IS (2.0L Turbo / 3.5L V6 (IS 350 311HP) / 5.0L Naturally Aspirated V8 (IS 500 472HP)), 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 IS?
On the Lexus IS, the 16-pin DLC diagnostic connector is located Driver A-pillar base kick panel. 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 IS 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.
