CorollaFix

P2138 on Toyota Corolla E170: Throttle/Pedal Position Sensor/Switch D/E Voltage Correlation

Short answer: P2138 means “Throttle/Pedal Position Sensor/Switch D/E Voltage Correlation”. The car’s computer has found a fault in the ETCS (throttle) system and turns on the Check engine light (MIL). First check: read the code with an OBD-II scanner.

Standard OBD-II code Same meaning on all cars (SAE J2012). Not checked against this car’s factory manual.

Code
P2138
System
ETCS (throttle)
Dashboard light
Check engine light (MIL)
Applies to
Generic OBD-II meaning. Not every code is used by this car.
Confidence
medium (generic OBD-II definition, not checked against the factory manual for this car)
Source
obd-codes.com

Symptoms and when it is set

  1. Check engine light on
  2. Symptoms of a P2138 code can range from stalling when you come to a stop, total lack of power, no acceleration, sudden loss of power at cruise…
  3. Potential Causes of P2138 DTC
  4. It's been my experience that the wiring connector or "pig tail" on the throttle body gives problems in the form of a poor connection.The female…
  5. Possible bare wire on pigtail shorting to ground
  6. The top cover on the throttle body distorted preventing the gears from turning properly

Likely causes

  1. Fault in the part or circuit named in the code

What to check, in order

  1. Read the code with an OBD-II scanner
  2. Check the throttle body and pedal sensor connectors
  3. Clean a dirty throttle body; do not force the valve by hand
  4. Clear the code; some cars need an idle relearn after cleaning

Related on this car

Same code on other cars

← P2135 P2195 →

Clearing the code does not fix the fault. If it comes back, the problem is still there. For brakes, airbags and steering, see a trained mechanic.