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P2138HondaHonda Platform HubMaster P2138 GuideCritical Severity

P2138 on Honda: Symptoms, Causes & DIY Fix

Official technical diagnostic wire for fault code P2138 (P2138: Throttle/Pedal Position Sensor/Switch D / E Voltage Correlation) specifically affecting Honda vehicles (Civic, Accord, CR-V, Pilot, HR-V).

DIY Parts Estimate
$180 - $480 (DIY: $50 - $140)
Honda OEM Direct Fit
Shop Labor Quote
$180 – $380
Based on $115/hr labor
Drivability Status
Not Drivable
Critical urgency level
Est. DIY Time
45 – 90 Min
Basic hand tools
Check P2138 On Another Make:
ToyotaBMWMercedes-BenzLexusFordHyundaiCadillacTeslaChevroletHondaAudiNissanJeepKiaSubaruRAMGMCVolkswagenMazdaDodgeVolvoBuickLincolnChryslerAcura

1. Symptoms of P2138 on Honda

When the Engine Control Module (ECM/PCM) on your Honda logs fault code P2138, drivers commonly observe:

System alert or indicator light illuminated (P2138) on Honda (Civic, Accord)
Intermittent performance throttling or unexpected operation halts on Honda (Civic, Accord)
Audible sensor relay clicking or anomalous status telemetry in dashboard logs on Honda (Civic, Accord)
Degraded operational throughput or error dialog popups on startup on Honda (Civic, Accord)
Readiness monitors failing state emissions or system compliance audits on Honda (Civic, Accord)

2. Most Likely Causes on Honda

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

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Outdated firmware microcode or incompatible software driver update (Honda OEM Part)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

3. Step-by-Step DIY Repair Guide for Honda

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 Honda vehicles (Civic, Accord).

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 Honda vehicles (Civic, Accord).

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 Honda vehicles (Civic, Accord).

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 Honda vehicles (Civic, Accord).

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 Honda vehicles (Civic, Accord).

Required Tool: OBD-II Code Reader / Diagnostic Suite

P2138 Guides by Honda Model

Select your specific Honda model below for exact OBD-II DLC port locations, wiring diagrams, and engine displacement specs:

Other Common Diagnostic Codes on Honda

Troubleshoot other high-frequency Check Engine Light fault codes reported across Honda vehicles:

4. Honda P2138 FAQs

What causes code P2138 to trigger on a Honda?

On Honda vehicles, 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. Factory sensor degradation or wiring harness wear near the engine bay are common factors.

Can I safely drive my Honda 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 on Honda vehicles, we advise performing diagnostic scanning via the OBD-II port before extended driving.

How much does it cost to fix P2138 on a Honda?

DIY replacement parts typically range between $180 - $480 (DIY: $50 - $140). If serviced at an authorized Honda dealership, expect an additional $120–$250 in professional labor based on their $115/hr hourly rate.