WagonRFix

P0120 on Suzuki Wagon R: Throttle Position Sensor A Circuit Malfunction

Short answer: P0120 means “Throttle Position Sensor A Circuit Malfunction”. The car’s computer has found a fault in the Engine system and turns on the Check engine light (MIL). First check: read the code and freeze-frame data 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
P0120
System
Engine
Dashboard light
Check engine light (MIL)
Also sold as
Maruti Suzuki Wagon R, Suzuki Karimun Wagon R (Indonesia)
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. Potential symptoms include
  3. Misfiring at idle or at highway speed
  4. Poor idle quality
  5. Possibly won't idle
  6. Possibly starts and stalls

Likely causes

  1. Potential causes of the P0120 code include
  2. Sticking throttle return spring
  3. MAP or TPS connector corrosion
  4. Misrouted harness causing chafing
  5. Bad TPS
  6. Bad PCM

What to check, in order

  1. Read the code and freeze-frame data with an OBD-II scanner
  2. Check the connector and wiring of the part named in the code
  3. Test the part with scanner live data or a multimeter, using the values in the repair manual
  4. Fix the cause, clear the code and test-drive

Related on this car

Same code on other cars

← P0118 P0121 →

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.