What P0122 Means for Your 2019 Honda Accord
A P0122 on your 2019 Honda Accord tells the ECM that the throttle position sensor signal has dropped below the minimum voltage threshold. This is a circuit-level fault—the electrical pathway between the TPS and ECM has broken down. Our detective has found that the signal line has gone dark, not just fuzzy.
The 2019 Accord (10th generation) uses a 1.5L VTEC turbo (192 hp) or 2.0L VTEC turbo (252 hp). At 5–7 years old, connector corrosion and component wear are leading causes of circuit faults.
Symptoms
- Check engine light on
- Severe throttle loss or failure
- Engine idles but won't accelerate
- Harsh limp mode
- Stalling risk
Causes
- Connector corrosion – Oxidized or damaged pins from years of heat and moisture exposure. Likelihood: 35%
- Throttle body failure – Internal TPS sensor short or open from age. Likelihood: 30%
- Wiring degradation – Aged insulation, chafing, or heat damage. Likelihood: 20%
- Reference voltage issue – 5V reference pulled low by another sensor fault. Likelihood: 10%
- Ground circuit problem – Corroded engine ground. Likelihood: 5%
Repair Costs
- Connector repair: $50–$150
- Throttle body replacement: $280–$500 parts and labor
- Wiring repair: $150–$350
Warranty & DIY
The basic warranty has expired. The powertrain warranty (5 years/60,000 miles) may still apply if under 60,000 miles. The federal emissions warranty (8 years/80,000 miles) covers through 2027. Check eligibility before paying. For DIY, inspect the connector first—clean pins with contact cleaner, check for 5V reference with a multimeter, verify ground continuity. If electrical checks pass, replace the throttle body. Honda idle relearn: key ON 10 seconds, start, idle 10 minutes.
How AutoDetective AI Can Help
Upload your scan data to AutoDetective for a free diagnosis that determines whether your P0122 is a connector fix or a throttle body replacement.