What Does P0121 Mean on a 2024 Ram 1500?
A P0121 code on your 2024 Ram 1500 indicates the PCM has detected an abnormal voltage pattern from the throttle position sensor (TPS). The signal is present but doesn't match expected behavior. On a full-size truck, throttle precision is critical—especially for towing—so this code deserves prompt attention.
The 2024 Ram 1500 offers multiple powertrains: the 3.6L Pentastar V6 with eTorque mild-hybrid, 5.7L Hemi V8 with eTorque, or the new 3.0L Hurricane twin-turbo inline-six. The Pentastar uses port injection, the Hemi uses port injection with MDS cylinder deactivation, and the Hurricane uses direct injection. All have electronic throttle control with integrated TPS. At low mileage, software calibration is the primary suspect.
Top Causes of P0121 on the 2024 Ram 1500
- PCM software calibration – New model year; updates common. Likelihood: 40%
- Factory throttle body defect – Manufacturing issue. Likelihood: 25%
- Connector assembly issue – Not properly seated. Likelihood: 15%
- eTorque system interaction – 48V mild-hybrid torque fill affecting correlation. Likelihood: 15%
- Carbon buildup – Unlikely at low mileage. Likelihood: 5%
Symptoms You May Notice
- Check Engine Light on
- Rough or inconsistent idle
- Hesitation during acceleration
- Reduced towing power
- MDS may not engage properly (Hemi)
- Cruise control issues
How Serious Is This Code?
P0121 is medium severity. Your 2024 Ram 1500 remains drivable, but throttle issues on a towing vehicle need quick resolution. Address it soon—schedule a dealer visit within the week.
Diagnostic Steps
- Take the Ram to your dealer—warranty covers this
- Dealer uses wiTECH for Stellantis diagnostics
- Check for software updates specific to your engine option
- Inspect throttle body connector and wiring
- Monitor TPS alongside eTorque and MDS data
- Replace throttle body if hardware fault confirmed
Estimated Repair Costs
- Under warranty: $0 (Stellantis 3-year/36,000-mile basic warranty)
- PCM reflash: $0 under warranty
- Throttle body replacement (if out of warranty): $350–$700
Should You DIY This?
DIY feasibility is low. Your 2024 Ram 1500 is fully covered under Stellantis' 3-year/36,000-mile basic warranty and 5-year/60,000-mile powertrain warranty. Let the dealer handle it at no cost. wiTECH is required for proper diagnostics, especially for the new Hurricane engine.