📌 What does code P2135 mean?
Code P2135 is an OBD-II code that indicates a disagreement between the two throttle position sensors (TPS) in the electronic throttle body. These sensors should return consistent values. If the ECU detects a persistent difference, it triggers this error code to warn of a potential malfunction in the acceleration system.
⚠️ Severity of the code
High. This code can cause stalling, a sudden loss of power, or a stuck accelerator, which can pose a driving hazard. It is strongly advised not to ignore this code.
🚨 Common symptoms:
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Stalling when stopping
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No or very little response to acceleration
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Sudden loss of power while driving
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Engine RPM stuck
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Check Engine light on
🔍 Common causes of P2135:
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Corroded, poorly connected, or damaged connector (“pigtail”) at the throttle body
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Short to ground in the TPS sensor wiring
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Deformed upper cover of the throttle body, disrupting internal gears
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Faulty electronic throttle body
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Faulty accelerator pedal sensor
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Engine control unit (ECU/PCM) problem
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Uncorrelated TPS: the ECU may require a relearning phase or reprogramming
🧰 Diagnostic and repair steps:
1. 📄 Search for TSBs (Technical Service Bulletins)
These bulletins may document known cases for your model and provide manufacturer-approved solutions.
2. 🧪 Sensor relearn
Some vehicles require a TPS sensor reset procedure. Example for a Nissan:
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Ignition: ON position (engine off)
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Press and release the pedal 5 times within 5 seconds
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Wait 7 seconds, then press and hold for 10 seconds (light flashes)
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Release, wait 10 seconds, then press again for 10 seconds
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Turn off the ignition
⚠️ Procedure varies by brand: check your technical manual.
3. 🔌 Inspection of the throttle body connector
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Disconnect the connector, check the condition of the pins (bent, corroded, pushed in)
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Clean with a small screwdriver and apply dielectric grease
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If damaged, replace the pigtail connector (available at auto parts stores)
4. 🔎 Check of the throttle body upper cover
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Check for absence of cracks or deformation
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This fragile cover houses the throttle gears
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If damaged, replace the throttle body (or the cover if sold separately)
5. 🔧 Test of the accelerator pedal sensor
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Using a voltmeter:
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5V reference and variable signal from 0.5V to 5V
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Slowly press the pedal: the voltage should rise linearly
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If voltage jumps or no signal: faulty sensor
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6. ⚡ Check of the throttle body motor power supply
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Identify the terminals (via manufacturer diagram)
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Test for current with pedal pressed and ignition ON
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No current = faulty ECU, current present but no movement = faulty throttle body
7. 🧩 Address other related codes
If codes like P2136 are present, address them first: they may be the underlying cause of P2135.
🛠️ Common repairs:
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Cleaning or replacement of the TPS pigtail connector
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TPS relearn or ECU reprogramming
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Replacement of the accelerator pedal sensor
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Replacement of the electronic throttle body
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Repair of the TPS wiring harness
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Replacement of the engine control unit (if confirmed faulty)
❌ Common mistakes to avoid:
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Do not directly replace the throttle body without checking the wiring and connector, as this is one of the most common causes.
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Do not neglect reprogramming or relearning after repair: it may be essential to fix the problem.