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OBD-II trouble code

P2140: Throttle/Pedal Position Sensor 'E'/'F' Voltage Correlation

The last pair in the correlation grid, and the one that makes the grid readable. Which correlation codes are stored together is a truth table: with three channels cross-checked in pairs, the pattern of what set and what did not identifies the faulty channel before a single measurement is taken.

High severityPowertrainThrottle / IdleDrivable short-term

Quick facts

System
Powertrain
Category
Throttle / Idle
Severity
High severity
Drivable
Usually safe to drive short-term
Repair cost range
$0$750
DIY difficulty
Intermediate DIY

Browse every code in P2100–P2199, or start from the full code library.

What does P2140 mean?

P2140 sets when the module compares the 'E' and 'F' position channels and finds their relationship has drifted outside tolerance. As with every correlation code, both signals are electrically valid on their own — what has failed is the agreement between them, so testing either channel in isolation will usually show nothing wrong.

P2140 completes the cross-check grid for the second group of position channels. With D, E and F all present, the module can compare three pairs: D against E, D against F, and E against F. Those three comparisons have their own codes — P2138, P2139 and P2140 — and the reason that matters is that the set of codes stored together is itself a diagnosis. This is the code that makes that readable, because it is the pair that excludes D.

Work through it. If exactly one channel has developed an offset, it appears in both of the pairs that include it and in neither of the pair that does not. A faulty D shows as P2138 and P2139 together, with P2140 absent. A faulty E shows as P2138 and P2140, with P2139 absent. A faulty F shows as P2139 and P2140, with P2138 absent. The channel that is missing from the code list is the channel that is innocent, and the one that appears in both stored codes is the one to go after. That is not an inference from symptoms or a probability argument — it follows from which comparisons the module ran and which ones failed, and it is available from the scan tool before anything is unplugged.

Two caveats keep this honest. A single stored correlation code, on its own, does not identify anything: P2140 alone means E and F disagree and says nothing about which of the two is wrong, because the third comparison either passed or was never evaluated. And the logic assumes one fault. Two channels drifting together, a module input problem, or a supply fault touching more than one circuit can set all three codes at once, at which point the pattern stops pointing anywhere and the diagnosis reverts to measuring each channel against known-good values rather than against each other. All three correlation codes present is a signal to look at something common — a supply, a ground, a module — rather than at any individual channel.

The other thing worth knowing about this particular pair is that neither member of it is usually the channel the module commands from. On most implementations the primary torque request is built around the pedal's main track, and E and F are both confirming channels — the second pedal track and the third position input. When two confirming channels disagree with each other while both still agree acceptably with the primary, there is often no driveability consequence at all. The vehicle drives normally, the owner has nothing to report, and the code is found when someone scans for something else. That makes P2140 easy to leave, and leaving it means the module has lost the ability to resolve any future disagreement by majority — which is the whole reason the third channel is fitted.

Common causes

  • Offset developing inside the E channel's sensing element with wear
  • Offset developing inside the device carrying the F channel
  • High resistance on one channel's ground or reference skewing only that reading
  • Relearn not performed after a pedal, control or module replacement
  • Non-equivalent replacement part with a different output characteristic
  • Corroded or backed-out terminal on one of the two channels' connectors
  • Harness damage affecting one channel's circuits only
  • Mechanical wear or play in the control carrying one of the two channels
  • Restricted travel preventing one channel from reaching its expected values
  • Module input circuit fault affecting one channel, which is rare and usually sets all three pairs

Symptoms

  • Check engine light with one or more stored correlation codes
  • Vehicle driving entirely normally, since neither channel may be the commanding one
  • Code discovered during an inspection or a scan for an unrelated concern
  • Reduced engine power warning where the drift has grown enough to reach the primary channel
  • Two position traces running parallel but offset from each other on a graph
  • A second correlation code appearing alongside this one and naming the faulty channel by elimination
  • All three correlation codes stored together, which points at a shared supply or the module
  • Loss of an auxiliary control function on applications where F serves one
  • Cruise control unavailable while the fault is stored
  • Code returning after a clear with no change in how the vehicle behaves

Diagnostic steps

  1. 1.Read the entire stored code list before anything else and write down which of the three correlation codes are present. That list, on its own, is the most informative thing available on this fault.
  2. 2.Apply the elimination. Two correlation codes sharing one channel point at that channel; the comparison that is absent exonerates the channel it omits. P2140 with P2139 implicates F, P2140 with P2138 implicates E.
  3. 3.Treat a single P2140 with no partner code as undetermined. One failed comparison identifies a disagreement, not a culprit, and proceeding as though it named one wastes the advantage the grid gives you.
  4. 4.Treat all three correlation codes together as a different problem entirely. That pattern is not three faults; it is usually one shared supply, one ground, or a module input issue, and individual channel testing is the wrong next step.
  5. 5.Ask what work has been done recently. A relearn that was never performed, or a substituted part with a different output curve, produces a permanent offset on hardware that tests perfectly.
  6. 6.Graph all available position channels together and sweep slowly through full travel. Parallel traces with a fixed gap indicate calibration or part equivalence; a gap that opens at one position indicates wear.
  7. 7.Verify the reference and ground for the implicated channel specifically, testing the ground under load rather than for continuity alone.
  8. 8.Inspect the implicated channel's connector for corrosion, a backed-out terminal or lost terminal tension before ordering any part.
  9. 9.Check mechanical travel on the control carrying the implicated channel, including stops, linkage play and anything obstructing full movement.
  10. 10.Clear the codes after the repair and confirm across a full drive cycle that none of the three correlation codes returns, since fixing one channel can unmask a second that was previously outvoted.

Repair cost

$0$750

A missed relearn after previous work is a zero-parts outcome and is common enough to check for first. Diagnosis is $110 to $240 and is often quicker than the other correlation codes, because reading the pattern of stored codes narrows the search before any testing starts. A terminal or circuit repair on the implicated channel is $90 to $280. An accelerator pedal assembly is $180 to $450 fitted, since individual tracks are not serviced. An auxiliary control carrying the F channel, with its harness section, runs $250 to $750. Where all three correlation codes are stored, expect diagnosis at the upper end and a shared supply, ground or module as the likely cause.

Estimate your repair

Run the numbers for your vehicle

Open the Repair Cost Estimator with accelerator pedal position sensor replacement preselected. Adjust labor rate and vehicle category to fit your situation.

DIY vs shop

This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.

Related codes

Frequently asked questions

Can I keep driving with P2140?

Usually yes in the short term, and on many vehicles you will notice nothing at all, because the two channels being compared here are often both confirming inputs rather than the one the module builds its torque request from. If a reduced power warning has appeared, the drift has grown far enough to affect the primary channel and the vehicle should only be driven far enough to reach a shop, off fast roads. Either way the repair matters: the point of a third channel is that one fault can be outvoted, and that ability is what this code says you no longer reliably have.

How can the codes tell you which sensor is bad before testing anything?

Because three channels get compared in three pairs, and a single faulty channel shows up in exactly the two comparisons that include it. If D is the problem you get the D/E and D/F codes and not the E/F one. If E is the problem you get D/E and E/F, but not D/F. If F is the problem you get D/F and E/F, but not D/E. So the comparison that is missing from your code list is the one that omits the faulty channel, and the channel appearing in both stored codes is the suspect. It comes straight off the scan tool. Two caveats: one correlation code on its own proves nothing about which channel is wrong, and all three together usually means a shared supply or the module rather than three bad sensors.

Only P2140 is stored. What does that tell me?

That E and F disagree, and nothing more than that. The elimination trick needs a second correlation code to work, because it depends on knowing which comparison passed. With one code you know two channels are no longer in agreement but not which of them moved. From there it is ordinary work: graph both against the third channel and against travel, check each one's own reference and ground, and look at what has been replaced recently. Do not pick one of the two because it is cheaper or easier to reach — that is guessing, and on sealed assemblies the guess is expensive.

Why would all three correlation codes be stored at once?

Because something the channels have in common has gone wrong, rather than three separate sensors failing on the same day. A reference supply that has drifted, a shared ground with resistance in it, or a module input problem can shift several channels at once in different amounts, and every pair then fails its comparison. The useful response is to stop testing individual sensors and go after what is shared: measure the reference voltages, voltage drop test the grounds under load, and check whether a module has recently been reprogrammed or restored to defaults. Replacing sensors against a three-code pattern is how people end up several parts into a fault that was never in a sensor.

Editorial context

About This Diagnostic Information

AutoLogicTools diagnostic guides explain OBD-II trouble codes using recognized code definitions, standard automotive diagnostic principles, and practical automotive context. A trouble code records a condition detected by a control module. It does not automatically identify a failed part, and the right diagnostic procedure can vary by vehicle.

Manufacturer service information, technical service bulletins, wiring diagrams, and vehicle-specific procedures should take precedence when available.

AutoLogicTools was founded by Vincent Fisk, an automotive locksmith and shop owner in San Diego with hands-on experience in vehicle keys, immobilizer systems, electrical issues, modules, programming, and diagnostics.