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P0123KiaKia Forte HubAll Kia P0123Critical Severity

P0123 on Kia Forte

Throttle/Pedal Position Sensor/Switch A Circuit High Input

Factory diagnostic protocol and troubleshooting wire for fault code P0123 specifically for the Kia Forte (2020–2026, 2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP)).

Verified OEM Telemetry & Field Repair Tree
Kia Forte2020–2026
Kia Forte
Sedan2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Forte SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$140 - $420
Parts & Labor DIY
Check P0123 On Another Kia Model:
Diagnose P0123 on Specific Forte Model Year:

1. Symptoms of P0123 on Kia Forte

When the Engine Control Module (ECM/PCM) on your Kia Forte (2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP)) logs fault code P0123, drivers commonly observe:

Check Engine Light on on Kia Forte (2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP))
High idle speed (1,500+ RPM) on Kia Forte (2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP))
Limp mode on Kia Forte (2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP))
Kia Forte OBD-II Port Location
The 16-pin diagnostic connector is located Behind driver dash bezel near knee panel. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Kia Forte

Historical warranty claims and technical repair bulletins for Kia Forte point to the following failure distribution:

55%
TPS signal shorted to 5V reference (Kia OEM Part)
25%
Broken sensor ground wire (Kia OEM Part)
12%
Defective electronic throttle body (Kia OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Kia Forte.

3. Step-by-Step DIY Repair Guide for Kia Forte

01
Scan and Record Freeze Frame Telemetry

Connect an OBD-II scan tool and record freeze frame sensor telemetry for code P0123 to note engine RPM, load, and voltage when the fault triggered. on the Kia Forte equipped with 2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP).

Required Tool: OBD-II Scanner
02
Inspect Related Wiring Harness & Connectors

Inspect the electrical connector and wiring harness related to P0123 for chafing, corrosion, moisture, or pin push-out. on the Kia Forte equipped with 2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP).

Required Tool: Flashlight, Multimeter
03
Test Component Resistance & Voltage Supply

Measure circuit voltage supply (12V B+ or 5V reference) and sensor/actuator resistance according to factory repair manual specifications. on the Kia Forte equipped with 2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP).

Required Tool: Digital Multimeter
04
Replace Defective Component

Install a new OEM-grade replacement part, torque fasteners to factory spec, and ensure electrical locking tabs click firmly. on the Kia Forte equipped with 2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP).

Required Tool: Hand Tool Socket Set, Torque Wrench
05
Clear Trouble Codes & Complete Drive Cycle

Clear all stored DTCs from vehicle memory and perform an OBD-II drive cycle to confirm the diagnostic monitor resets to 'Ready'. on the Kia Forte equipped with 2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP).

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Kia Forte (P0123)

Prime Fast Delivery & Verified Fitment
Variable Valve Timing (VVT)

VVT Oil Control Solenoid Valve

4.6 / 5.0 (Direct Fit)

Restores accurate camshaft timing and oil pressure regulation on Kia Forte.

$34 – $65 Prime
Check Fitment on Amazon
Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Kia ForteVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Kia Forte

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Kia Forte:

4. Kia Forte P0123 FAQs

What causes code P0123 to trigger on a Kia Forte?

On the Kia Forte (2.0L Smartstream 4-Cyl (147HP) / 1.6L Turbo GT (201HP)), P0123 is most frequently caused by TPS signal shorted to 5V reference or Broken sensor ground wire.

Where is the OBD-II port located on my Kia Forte?

On the Kia Forte, the 16-pin DLC diagnostic connector is located Behind driver dash bezel near knee panel. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Kia Forte with code P0123?

No. Throttle signal pegged at 5.0V. Given that P0123 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.