P1337 — Throttle Position Output Signal Fault

P1337 — Throttle Position Output Signal Fault. P1337 can affect throttle-command accuracy and may trigger reduced-power operation.

For Ford vehicles

throttle position circuit output signal

vehicle

Is it safe to drive?

Reduced throttle response may be present P1337 can affect throttle-command accuracy and may trigger reduced-power operation. Avoid hard acceleration and heavy load until the fault is diagnosed; if the engine stalls, loses throttle response, or enters a severe fail-safe, stop safely and have it inspected.

Typical symptoms

  • The check-engine light may illuminate with P1337 stored
  • Engine idle may be unstable, unusually high, or prone to stalling
  • The engine may hesitate or surge when accelerator pedal pressure is applied
  • Throttle response may feel delayed or reduced
  • The vehicle may enter a fail-safe or reduced-power operating mode

Common causes

  • A defective throttle-position sensor or throttle-body position sensor
  • An open circuit or high resistance in the throttle-position output wire
  • A short to battery voltage or ground in the throttle-position signal circuit
  • Corrosion, looseness, or damage in the throttle-position sensor connector
  • A poor sensor ground or an incorrect reference voltage at the sensor
  • A powertrain control module input failure or an intermittent wiring fault

How to diagnose with an OBD scanner

  1. Capture P1337 scan data Connect an ELM327 adapter to the OBD port and use AIScanAuto or a similar scanner to read stored and pending codes. Record freeze-frame data, especially engine speed, throttle position, and vehicle speed, before clearing any codes.
  2. Watch the throttle-position signal Use the scanner's live-data function to observe throttle-position output voltage and percentage with the ignition on. Slowly move the throttle as specified for the vehicle and look for signal dropouts, abrupt jumps, or readings outside the manufacturer-defined range.
  3. Inspect the sensor and harness Examine the throttle-position sensor connector and related wiring for corrosion, bent terminals, chafing, or water intrusion. Check the wiring between the sensor and powertrain control module while moving the harness to expose an intermittent P1337 condition.
  4. Test reference, ground, and output Back-probe the sensor connector and compare the reference voltage, sensor ground, and throttle-position output with manufacturer specifications. A valid reference and ground combined with an invalid output points toward the sensor; an invalid signal at the control module also requires circuit testing.
  5. Repair and verify P1337 Repair the confirmed wiring or connector fault, or replace the throttle-position sensor or throttle body when testing supports it. Clear P1337 with the scanner, perform a controlled road test, and confirm that the code does not return and the throttle signal remains stable.

Approximate repair cost

A rough independent-shop estimate for diagnosing and repairing P1337 is $180–$750 USD, depending on whether the fault is a wiring repair, sensor replacement, or throttle-body replacement. These figures are estimates only and vary by region, labor rates, and parts availability.

Common questions

What does P1337 mean on this vehicle?

P1337 identifies a problem with the throttle-position output signal or the circuit carrying that signal to the powertrain control module.

Can I keep driving with P1337 stored?

Driving may be possible, but throttle response can be reduced and the engine may stall or enter fail-safe mode. Avoid hard acceleration and seek diagnosis promptly.

Is the throttle-position sensor always the cause of P1337?

No. P1337 can also result from damaged wiring, a bad connector, an incorrect reference voltage, poor ground, or a control-module input problem.

How can an ELM327 scanner help diagnose P1337?

An ELM327 scanner can confirm the code, preserve freeze-frame information, and display live throttle-position data so signal dropouts can be checked during testing.

P1337 — ---

When your engine control unit detects a signal that falls outside its expected operating window, it logs a specific trouble code to flag the problem. P1337 appears when the powertrain management system identifies a sensor or actuator circuit that isn't behaving as it should. The vehicle's computer constantly evaluates electrical feedback from critical engine components, and when readings stray beyond acceptable thresholds across multiple drive cycles, the system records this fault and activates the Check Engine light. The stored freeze frame snapshot captures the exact engine conditions—RPM, load, temperature, and vehicle speed—at the moment the anomaly occurred, giving technicians a precise starting point for troubleshooting.

P1337 doesn't identify a single failed component. Instead, it indicates a broader circuit malfunction affecting one of the vehicle's monitored systems. The ECU sees the symptom (unexpected behavior) but flags it under this generic category code until closer inspection pinpoints the actual root cause. Once the underlying fault is confirmed and corrected, the code can be cleared and the warning light extinguished.

Symptoms

A stored P1337 typically produces these observable effects:

  • Check Engine Light illuminated on the dashboard
  • Vehicle may enter limp-home mode depending on which specific system is affected
  • The affected system functions intermittently or stops working entirely
  • Noticeable drop in fuel economy under certain driving conditions
  • Reduced engine performance in some vehicle applications

Common Causes

The following issues most frequently trigger P1337, listed from most to least common:

  • Wiring damage including opens, shorts, or chafed insulation in the affected circuit
  • Blown fuse protecting the circuit that feeds the malfunctioning component
  • Poor or corroded ground connection at the affected sensor or actuator
  • Faulty sensor or actuator within the monitored circuit
  • Control module driver failure or internal circuitry fault

Diagnostic Steps

Follow this logical sequence to isolate the root cause:

  1. Connect an OBD2 scanner and verify P1337 is stored. Record all freeze frame data — these parameters show exactly what the engine was doing when the fault occurred.
  2. Check for any related or supporting diagnostic trouble codes. Co-occurring codes often point directly to the failing component. Search manufacturer TSB databases using your VIN for known software updates or factory remedies.
  3. Perform a thorough visual inspection of the wiring harness and connectors in question. Look for damaged insulation, bent pins, corrosion buildup, or loose connections.
  4. Test electrical integrity at the component connector — verify proper reference voltage, confirmed ground, and signal continuity.
  5. Conduct a wiggle test on the harness while monitoring live data. Any signal dropouts indicate intermittent wiring failure.
  6. Clear the code and drive the vehicle through the specific conditions captured in the freeze frame data. If P1337 returns, the fault is confirmed and persistent.

Repair Options and Costs

Target the least expensive likely causes before replacing major components:

  • Sensor or actuator replacement: $150–$500
  • Wiring repair or connector replacement: $80–$250
  • Control module diagnosis and repair: $300–$1,000

Total repair cost for P1337 depends entirely on which part is at fault. The complete range spans $80 to $1,000 depending on whether you're fixing a simple wiring issue or rebuilding a faulty control module. Accurate diagnosis before purchasing parts is essential — the priciest scenario is rarely the first place to look.

Can You Drive With P1337?

P1337 carries a short-term driving safety rating. Most vehicles remain operational with this code stored, though you may experience reduced performance or loss of certain auxiliary functions. If the malfunction causes stalling, prevents starting, or triggers brake and steering warnings, address it immediately regardless of the code's general severity.

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