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OBD-II trouble code

P2299: Brake Pedal Position / Accelerator Pedal Position Incompatible

The module was told the brake was applied and the accelerator was pressed at the same time, decided that combination should not exist, and cut throttle authority. More often than not the cause is a brake switch, a floor mat or a driving habit — not a failed sensor.

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$600
DIY difficulty
Intermediate DIY

Browse every code in P2200–P22A0, or start from the full code library.

What does P2299 mean?

Two inputs that have no other reason to talk to each other are being compared here. One is the brake pedal — usually a switch, sometimes a position sensor, on many vehicles both at once for redundancy. The other is the accelerator pedal position sensor. Neither measures the other and neither depends on the other. The module simply holds a rule about the pair: a driver should not be commanding meaningful acceleration while the brakes are applied, and if both inputs say so simultaneously for long enough, one of them is lying.

That rule exists because of brake-throttle override. On a drive-by-wire vehicle the accelerator pedal is a request, not a linkage, and the module is the thing that decides how much of the request to grant. Every modern powertrain is built so that a braking input wins that argument. So when P2299 sets, the reduced power the driver complains about is not the fault — it is the safety logic doing precisely what it was designed to do with the information it was given. Understanding that changes the diagnosis completely: the question is never why the throttle was cut, it is which of the two inputs was wrong.

And very often neither one is wrong. This is one of the few generic powertrain codes where the leading explanation is the driver rather than the vehicle. Someone who brakes with the left foot and rests it lightly on the pedal while maintaining throttle will produce this code on a car in perfect health, as will a heavy winter floor mat that has crept forward and is holding the brake pedal a few millimetres down, or a water bottle that has rolled under the pedals. Before any measurement is taken, ask how the car is driven and look at the floor. It costs nothing and it resolves a real share of these complaints outright.

When the vehicle genuinely is at fault, the brake side is where to look first and it is cheaply eliminated. The brake light switch is a small adjustable assembly behind the pedal, it wears and it drifts out of adjustment, and when it does it reports a pressed pedal with the pedal at rest. You can test it without opening anything: watch the brake lights. If they glow with nobody in the car, or illuminate at the very first touch of the pedal before any braking effort exists, the switch has already told you what it is doing. That check takes seconds and a switch is a fraction of the cost of a pedal sensor assembly.

The accelerator side is the less common but more expensive possibility. Pedal position sensors are dual-channel by design, and a pedal whose channels have begun to disagree, or whose connector has corroded, can report a partly pressed accelerator that no foot is causing. That normally brings its own correlation codes along with it, which is a useful sorting rule: P2299 standing alone points at the brake side or at something physical near the pedals, while P2299 arriving with pedal circuit or correlation codes points at the accelerator assembly.

Common causes

  • Brake light switch out of adjustment or failing, reporting a pressed pedal at rest
  • Driver braking with the left foot and resting it on the pedal while maintaining throttle
  • Floor mat crept forward, or a loose object under the pedals, holding the brake pedal down
  • Brake pedal position sensor drifted out of its learned rest position
  • Accelerator pedal position sensor channel disagreement or contamination
  • Corroded or water-intruded connector at either pedal assembly
  • Chafed wiring in the footwell loom, where it is exposed to feet, moisture and road salt
  • A previous brake switch replacement fitted without setting its adjustment

Symptoms

  • Check engine light along with reduced or limited throttle response
  • Sudden loss of power when accelerating, sometimes recovering on its own
  • Vehicle refusing to rev past a limited point until the key is cycled
  • Brake lights staying on with the pedal released, or coming on far too early
  • Cruise control refusing to set or cancelling for no apparent reason
  • Reduced power warning message on the instrument cluster
  • Starting difficulty on push-button vehicles that require a valid brake input

Diagnostic steps

  1. 1.Walk around the vehicle with nobody inside and look at the brake lights. If they are lit with the pedal untouched, the brake switch has answered the question before any tool comes out.
  2. 2.Clear the footwell. Check that the mat is secured on its retainers, sits clear of both pedals and has not been layered over an older mat, and look for objects that have rolled underneath.
  3. 3.Ask how the vehicle is driven. Two-foot driving with the left foot resting on the brake pedal produces this code on a completely healthy car, and no amount of testing will find a fault that is not there.
  4. 4.Watch both pedal inputs live on a scan tool with the engine off and both pedals released. Anything other than a clean released reading on both is the fault.
  5. 5.Press the brake slowly and watch the point at which the input changes state. It should change as braking effort begins, not at the first trace of free play at the top of the travel.
  6. 6.Press the accelerator smoothly through its full range and watch both sensor channels track together. A step, a dropout or a divergence between channels indicts the pedal assembly.
  7. 7.Inspect and unplug both pedal connectors looking for green corrosion or moisture. Footwell connectors sit where wet shoes live and this is a real failure route rather than a formality.
  8. 8.After repair, confirm that full throttle authority has returned rather than assuming it. Some vehicles hold the reduced-power state until the code is cleared and the key has been cycled.

Repair cost

$0$600

A repositioned floor mat or a change of driving habit costs nothing, and that is a genuine outcome rather than a joke — a meaningful share of these complaints end there. A brake light switch is typically $90 to $220 fitted and is the most common real repair. An accelerator pedal position sensor assembly runs $180 to $500 fitted, and on many vehicles the sensor is not sold separately from the pedal. Footwell wiring or connector repair is $120 to $350. Diagnostic time is $90 to $180.

Estimate your repair

Run the numbers for your vehicle

Open the Repair Cost Estimator with brake light switch 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 P2299?

You can get the vehicle home or to a workshop, but do not put off the repair and be careful about where you drive in the meantime. The real hazard is not mechanical, it is that throttle can be reduced without warning while the fault is active. Losing power part-way through pulling into traffic or overtaking is a situation worth avoiding, so stick to routes and speeds where a sudden drop in power is manageable. Brakes, steering and lights are all unaffected.

Why did the car lose power when nothing is broken?

Because the module was doing exactly what it is built to do. On a drive-by-wire vehicle, braking always overrides the accelerator, so a module that believes both pedals are applied will reduce throttle deliberately. The power loss is the safety logic working correctly on information it had every reason to trust. The fault is upstream of that decision: one of the two pedal inputs was telling the module something that was not true, and that input is what needs finding.

Could this be caused by how I drive?

Yes, and it is worth ruling out before spending anything. Resting the left foot on the brake pedal while keeping throttle applied is enough to set this code on a car with nothing wrong with it, and the same goes for a floor mat that has shifted forward against the pedal or an item that has rolled underneath. Check the footwell, secure the mat on its retainers, and try driving with one foot for a while. If the code stays away, you have found it for free.

Is it the brake switch or the accelerator pedal?

Start with the brake switch, because it is far more likely and vastly cheaper, and you can check it from outside the car by looking at the brake lights with the pedal released. Use the rest of the stored codes as a sorting rule too: P2299 on its own usually points at the brake side or at something physical near the pedals, while P2299 alongside pedal position circuit or correlation codes points at the accelerator assembly instead. Confirm with live data on both inputs before buying either part.

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.