P0122 on Ford: Causes, Symptoms and Fix Cost
Quick Answer
Not safe to drive
P0122 on a Ford means the ECU is seeing an abnormally low voltage on throttle position sensor circuit A, typically under 0.2V when it expects 0.5V to 4.5V. Most cars drop into limp mode with capped throttle.
- Severity
- Moderate · Electrical
Connect a standard OBD2 adapter (Bluetooth LE on iPhone) to your Ford and Skanyx tells you what P0122 means on that engine, whether it is safe to keep driving, and what the fix should cost. Free on iPhone and Android.
Get Skanyx freeWhat does P0122 mean on a Ford?
The Quick Answer above is the generic definition. What follows is the model-specific detail for the Ford models that log P0122.
Ford F-150
2004-2010 (5.4L 3V Triton and 4.6L)
On these trucks the electronic throttle body wears at the sensor wiper track and starts reporting a low signal, and the APP (accelerator pedal position) sensor is also a known failure point. Check the harness where it passes near the intake manifold before ordering either part, because chafing there produces the same code.
What causes P0122 on a Ford?
Beyond the generic causes listed on the main P0122 page, these are the patterns noted for Ford models:
Failed accelerator pedal position sensor rather than the TPS itself
: Ford F-150
Chafed harness where it passes near the intake manifold
: Ford F-150
How to diagnose P0122 on a Ford with OBD2
- Read all stored codes and note companion codes such as P0222 or P2135, or other low-input codes such as P0107 that point to a shared 5V reference
- Watch live data for TPS1 voltage with key on, engine off. Below 0.2V confirms the low input
- Wiggle the throttle body connector and harness while watching live data to catch intermittent faults
- Backprobe the TPS signal, 5V reference, and ground pins with a multimeter. Reference should read 4.9 to 5.1V
- If reference and ground are good but signal stays near 0V, replace the TPS or throttle body
- If the 5V reference is missing, check the wiring back to the ECU for a short to ground
- After repair, clear codes and run the throttle body relearn per the manufacturer procedure (on some makes this needs manufacturer-level software)
- Road test and confirm TPS voltage sweeps smoothly from ~0.5V at closed throttle to ~4.5V at WOT
How much does P0122 cost to fix on a Ford? (EUR)
Estimated repair costs for P0122 in EUR, compiled across makes. Expect Ford parts and labour towards the upper end of each range.
| Repair | Parts Cost | Labor Cost | Total Estimate | DIY Difficulty |
|---|---|---|---|---|
| Clean and reseat throttle body connector | €0–€10 | €0–€40 | €0–€50 | Easy |
| Replace standalone throttle position sensor | €30–€120 | €40–€90 | €70–€210 | Easy |
| Replace electronic throttle body assembly | €180–€550 | €80–€180 | €260–€730 | Moderate |
| Repair damaged wiring or connector pins | €10–€40 | €60–€180 | €70–€220 | Moderate |
| ECU diagnosis and replacement (worst case) | €400–€1200 | €100–€250 | €500–€1450 | Professional |
Prices estimated as of October 2026. Costs vary by region, vehicle, and shop.
Codes related to P0122
These codes are often seen alongside P0122 or point to related issues, on any make:
Looking for the full P0122 reference (all makes, full diagnosis flow, complete repair cost matrix)? See the main P0122 guide