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P0120RAMRAM 2500 HubAll RAM P0120Critical Severity

P0120 on RAM 2500

Throttle/Pedal Position Sensor/Switch A Circuit

Factory diagnostic protocol and troubleshooting wire for fault code P0120 specifically for the RAM 2500 (2020–2026, 6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP)).

Verified OEM Telemetry & Field Repair Tree
RAM 25002020–2026
RAM 2500
Truck6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
2500 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 P0120 On Another RAM Model:
Diagnose P0120 on Specific 2500 Model Year:

1. Symptoms of P0120 on RAM 2500

When the Engine Control Module (ECM/PCM) on your RAM 2500 (6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP)) logs fault code P0120, drivers commonly observe:

Check Engine Light and 'Engine Power Reduced' on on RAM 2500 (6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP))
Gas pedal does not respond on RAM 2500 (6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP))
Rough surging idle on RAM 2500 (6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP))
RAM 2500 OBD-II Port Location
The 16-pin diagnostic connector is located Driver footwell below steering column near parking brake. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on RAM 2500

Historical warranty claims and technical repair bulletins for RAM 2500 point to the following failure distribution:

55%
Faulty Throttle Position Sensor (TPS) (RAM OEM Part)
25%
Worn throttle body gears (RAM OEM Part)
12%
Damaged electronic throttle wiring harness (RAM OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for RAM 2500.

3. Step-by-Step DIY Repair Guide for RAM 2500

01
Scan and Record Freeze Frame Telemetry

Connect an OBD-II scan tool and record freeze frame sensor telemetry for code P0120 to note engine RPM, load, and voltage when the fault triggered. on the RAM 2500 equipped with 6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP).

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

Inspect the electrical connector and wiring harness related to P0120 for chafing, corrosion, moisture, or pin push-out. on the RAM 2500 equipped with 6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP).

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 RAM 2500 equipped with 6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP).

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 RAM 2500 equipped with 6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP).

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 RAM 2500 equipped with 6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP).

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

Equipment for Diagnosing RAM 2500 (P0120)

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 RAM 2500.

$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 RAM 2500Verified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
Find Parts on Amazon
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Other Common Fault Codes on RAM 2500

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the RAM 2500:

4. RAM 2500 P0120 FAQs

What causes code P0120 to trigger on a RAM 2500?

On the RAM 2500 (6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP)), P0120 is most frequently caused by Faulty Throttle Position Sensor (TPS) or Worn throttle body gears.

Where is the OBD-II port located on my RAM 2500?

On the RAM 2500, the 16-pin DLC diagnostic connector is located Driver footwell below steering column near parking brake. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my RAM 2500 with code P0120?

No. Throttle response may be disabled or locked in Limp Mode. Given that P0120 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.