P0123 OBD-II Trouble Code: Throttle Pedal Position Sensor/Switch (TPS) A Circuit High Input

Our certified mechanics come to you · Get a fair and transparent estimate upfront


Cost of diagnosing the P0123 code

P0123 is a diagnostic trouble code (DTC) for "Throttle Pedal Position Sensor/Switch (TPS) A Circuit High Input". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $154.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $50.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate* Credit towards follow-up repair Earliest Availability
Ford $154.99 $50.0
Toyota $154.99 $50.0
BMW $164.99 $50.0

*Estimates may vary by market

SCHEDULE P0123 DIAGNOSTIC Get a fair and transparent estimate upfront

P0123 code definition

Throttle Pedal Position Sensor/Switch (TPS) A Circuit High Input

What the P0123 code means

P0123 is the generic OBD-II code which indicates that the Engine Control Module (ECM) has seen the TPS circuit A output voltage go above the sensor's expected voltage specification range.

What causes the P0123 code?

  • The TPS sensor circuit A range output to the ECM went above the specified voltage of 4.54 volts for more than 2 seconds, indicating a short in the sensor or wiring.

What are the symptoms of the P0123 code?

  • The Check Engine Light comes on and the ECM goes into failsafe mode by cutting current to the throttle actuator, causing the throttle valve to close to less than 6 degrees of plate opening.

  • The ECM controls fuel injection and timing to control engine speeds.

  • The vehicle would be able to be driven very slowly with limited throttle response.

  • The engine may idle higher than normal and not accelerate as well as before.

Note: The symptoms are determined by the manufacturer failsafe ECM strategy for the vehicle during a failure and may vary between manufacturers and vehicles.

How does a mechanic diagnose the P0123 code?

  • Scans and documents the codes received and views the freeze frame data to see when the code was set

  • Clears the OBD-II fault codes and re-tests the vehicle to see if the codes come back

  • Checks TPS connections and wiring for shorted or damaged wiring or connections

  • Compares the data between TPS circuit A and B on the scanner and if incorrect, performs the TPS pinpoint tests as per the manufacturer's recommendations

  • Repairs any wiring or connection shorts

  • Replaces the TPS as pinpoint test dictates, clears the codes, then road tests the vehicle

Common mistakes when diagnosing the P0123 code

  • Not visually inspecting connections and wiring first

  • Not scanning, documenting and clearing codes, then retesting for them to verify failures

  • Not verifying and repairing wiring or connector problems after sensor is replaced

  • Replacing the TPS sensor without making sure it is the problem

  • Not verifying whether the TPS sensor A and B circuit voltages are within specification before and after repair or replacements.

How serious is the P0123 code?

The P0123 code will cause the engine ECM to go into a failsafe mode, which will cause various drive issues until repairs are done. Depending on manufacturer's failsafe mode strategy, drive issues could include lack of acceleration, high idle, bucking or jerking, limited speeds, or stalling.

What repairs can fix the P0123 code?

Additional comments for consideration regarding the P0123 code

  • The P0123 code may be accompanied by other TPS codes, so following the manufacturer's pinpoint tests for each code received may be needed to find and fix the problem.

  • Most failures for code P0123 involve a defective TPS sensor, or a connector shorted internally.

  • All TPS codes will cause the ECM to go into the same failure mode; drive symptoms will be roughly the same.

Need help with a P0123 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

Check Engine Light
P0123
trouble codes

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0123 code.

SCHEDULE P0123 DIAGNOSTIC
Get a $50 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(8600)

Rating Summary
8017
273
65
46
199
8017
273
65
46
199
 at YourMechanic

Brandon

9 years of experience
133 reviews
Brandon
9 years of experience
Ford Escort L4-2.0L - Check Engine Light is on - Nashville, Tennessee
Brandon showed up ahead of schedule, was very personable and diagnosed my problems. He also scheduled my next appointments which will be with him.
 at YourMechanic

William

23 years of experience
33 reviews
William
23 years of experience
Lexus IS250 V6-2.5L - Check Engine Light is on - Mableton, Georgia
Arrived early which was great. William was courteous, and attentive to the issue. Even though it took several attempts I'm so happy he was determined to fix it and he did!
 at YourMechanic

Dan

40 years of experience
1080 reviews
Dan
40 years of experience
Plymouth Grand Voyager - Check Engine Light is on - Lawrenceville, Georgia
Mr. Dan Barber was quite patient, courteous and quite knowledgeable. From my observation, Mr. Barber appears to be quite professional.
 at YourMechanic

Christopher

9 years of experience
120 reviews
Christopher
9 years of experience
Ford Fiesta L4-1.6L - Check Engine Light is on - Smyrna, Georgia
Chris communicated with us each step of the way up until his arrival. He listened well, was knowledgeable, and was prepared. He took the time to diagnose the problem, explained the what, why and how and provided a solution. I would definitely recommend him and will use him again.


Related questions

The TPS error code P0123 appears only when the AC is on
Hello. The low charge in the A/C system (https://www.yourmechanic.com/services/ac-recharge) is going to cause the A/C compressor to work harder than it should. This will put a greater load on the engine and may cause your throttle position sensor (https://www.yourmechanic.com/services/throttle-position-sensor-replacement) to...
Crank no start - 2003 Dodge Grand Caravan
Hi. Some of the codes you have will cause drivability problems and may cause the van not to start. The code p0118 deals with your coolant temperature sensor and a bad coolant temperature sensor will cause the car not to...
I have a Code P0601 on the PCM. I replaced the PCM, and now I have a code P0118, code P0123, and code P0193.
Hi there, the short answer to your question is no . A PCM with a P0601 (https://www.yourmechanic.com/article/-p0601-obd-ii-trouble-code-internal-control-module-memory-check-sum-error-by-spencer-clayton) (which is a memory module error in the PCM) cannot reliably retrieve codes for the codes you list (P0118 (https://www.yourmechanic.com/article/p0118-obd-ii-trouble-code-engine-coolant-temperature-ect-sensor-circuit-high-open-problem-by-jay-safford) - coolant temp...

More related articles

P2563 OBD-II Trouble Code: Turbocharger Boost Control Position Sensor Circuit Range/Performance
P2563 code definition Turbocharger Boost Control Position Sensor Circuit Range/Performance What the P2563 code means P2563 is an OBD-II generic code. The...
P2177 OBD-II Trouble Code: System Too Lean Off Idle Bank 1
P2177 code definition P2177 is a general OBD-II diagnostic trouble code indicating a fault with the bank 1 too lean. This code...
B1203 OBD-II Trouble Code: Fuel Sender Circuit Short To Battery
B1203 means a circuit in the fuel tank sender has shorted. This is likely caused by a faulty wire, or the fuel tank sender could be defective.

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (844) 997-3624 · hi@yourmechanic.com