P2138 on SUBARU OUTBACK — Throttle/Pedal Position Sensor/Switch D/E Voltage Correlation

Q: "What does P2138 mean on a SUBARU OUTBACK?"

"P2138 indicates: Throttle/Pedal Position Sensor/Switch D/E Voltage Correlation. This is a powertrain code. 76 SUBARU OUTBACK owners have reported this to NHTSA."

Q: "What are the most common causes of P2138 on SUBARU OUTBACK?"

"Based on 76 NHTSA reports, the most commonly cited components are: Vehicle Speed Control, Electrical System,Vehicle Speed Control, Fuel/Propulsion System. These percentages are based on the component field in owner complaints."

Q: "Is P2138 serious on my SUBARU OUTBACK?"

"Of 76 NHTSA reports for this code on SUBARU OUTBACK, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic."

Q: "What should I do if my SUBARU OUTBACK shows P2138?"

"1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare."

What P2138 Means on Your SUBARU OUTBACK

P2138 is a diagnostic trouble code indicating: Throttle/Pedal Position Sensor/Switch D/E Voltage Correlation. This code relates to the powertrain system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

76 SUBARU OUTBACK owners have reported this issue to NHTSA across model years 2005-2007. Most reports come from the 2006, 2005 model years. The most commonly reported component is Vehicle Speed Control (42.1% of reports).

Real SUBARU OUTBACK Owner Reports

Source: NHTSA Complaints Database

"Every once in a while the gas pedal stops functioning. it happens at highway speeds as well as local roads. when it does happen you have to find a safe spot to pull over and shut off the engine for at least a minute or more. restart the car and the pedal comes back. this is very hazardous."

— 2005 SUBARU OUTBACK owner · VEHICLE SPEED CONTROL · Filed 10/01/2020

"Please refer to code p2138 - throttle/pedal position sensor switch with "d"/"e" voltage correlation dtc severity 2 of 3 repair -- i believe elaine chao should be made aware of the safety issues affecting the general public regarding this dangerous issue -- my subaru outback accelerator will shut dow"

— 2005 SUBARU OUTBACK owner · UNKNOWN OR OTHER,FUEL/PROPULSION SYSTEM · Filed 11/05/2020

"As i was driving, i all of a sudden lost all power and control from the gas pedal. the car decelerated and i was only able to idle forward. the gas pedal became completely unresponsive. i turned the car off and restarted it."

— 2005 SUBARU OUTBACK owner · FUEL/PROPULSION SYSTEM · Filed 11/06/2018

"1) recurring phantom revving (in neutral and/or clutch depressed, both while completely stopped and while slowing down from any and all speeds) upwards of 4-5k rpm with difficulty getting the rpms back to normal."

— 2005 SUBARU OUTBACK owner · VEHICLE SPEED CONTROL · Filed 04/15/2018

"Error code p2138: some failure of pedal sensor assembly while in motion. exact issue unknown. acceleration goes limp and pedal becomes non-responsive. has happened in both city and highway driving situations."

— 2005 SUBARU OUTBACK owner · VEHICLE SPEED CONTROL · Filed 03/07/2018

All reports filed by vehicle owners directly with the U.S. Department of Transportation.

📊 Complaint Trend by Model Year

12

'05

59

'06

5

'07

Common Causes on SUBARU OUTBACK

Based on NHTSA complaint component analysis for this vehicle.

VEHICLE SPEED CONTROL 42.1%

ELECTRICAL SYSTEM,VEHICLE SPEED CONTROL 10.5%

FUEL/PROPULSION SYSTEM 5.3%

VEHICLE SPEED CONTROL,ENGINE 3.9%

ELECTRICAL SYSTEM 3.9%

What To Do Next

1
Check for recalls on YOUR VIN
Go to nhtsa.gov/recalls and enter your VIN. If your vehicle is covered, repairs are free.
2
Get a proper diagnosis
A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50–$150) pinpoints the root cause before you spend money on parts.
3
Compare repair quotes
Get 2–3 quotes. Dealer vs. independent shop prices often differ 30–50% for the same repair.

Frequently Asked Questions

What does P2138 mean on a SUBARU OUTBACK? ▾

P2138 indicates: Throttle/Pedal Position Sensor/Switch D/E Voltage Correlation. This is a powertrain code. 76 SUBARU OUTBACK owners have reported this to NHTSA.

What are the most common causes of P2138 on SUBARU OUTBACK? ▾

Based on 76 NHTSA reports, the most commonly cited components are: Vehicle Speed Control, Electrical System,Vehicle Speed Control, Fuel/Propulsion System. These percentages are based on the component field in owner complaints.

Is P2138 serious on my SUBARU OUTBACK? ▾

Of 76 NHTSA reports for this code on SUBARU OUTBACK, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic.

What should I do if my SUBARU OUTBACK shows P2138? ▾

1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare.