P0120 on RAM 3500
Factory diagnostic protocol and troubleshooting wire for fault code P0120 specifically for the RAM 3500 (2020–2026, 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel)).
1. Symptoms of P0120 on RAM 3500
When the Engine Control Module (ECM/PCM) on your RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel)) logs fault code P0120, drivers commonly observe:
2. Most Likely Causes on RAM 3500
Historical warranty claims and technical repair bulletins for RAM 3500 point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for RAM 3500
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 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).
Inspect the electrical connector and wiring harness related to P0120 for chafing, corrosion, moisture, or pin push-out. on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).
Measure circuit voltage supply (12V B+ or 5V reference) and sensor/actuator resistance according to factory repair manual specifications. on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).
Install a new OEM-grade replacement part, torque fasteners to factory spec, and ensure electrical locking tabs click firmly. on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).
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 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).
Equipment for Diagnosing RAM 3500 (P0120)
VVT Oil Control Solenoid Valve
Restores accurate camshaft timing and oil pressure regulation on RAM 3500.
AstroAI Auto-Ranging Digital Multimeter
Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.
BlueDriver Bluetooth Pro OBDII Scan Tool
Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.
Other Common Fault Codes on RAM 3500
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the RAM 3500:
4. RAM 3500 P0120 FAQs
What causes code P0120 to trigger on a RAM 3500?
On the RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel)), 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 3500?
On the RAM 3500, the 16-pin DLC diagnostic connector is located Driver lower kick panel near emergency brake assembly. 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 3500 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.