P0203 on Ford: Causes, Symptoms and Fix Cost
Quick Answer
Safe to drive (short-term)
P0203 on a Ford tells you the engine computer found an electrical fault in the circuit of the cylinder 3 injector: open, shorted or outside its resistance limits. On a four-cylinder it is an inner cylinder next to cylinder 4, and on three-cylinder engines such as Ford's 1.0 EcoBoost it is the last cylinder in the row. Workshop wiring repairs cost about 65-220 EUR; a petrol injector fitted about 100-310 EUR.
- Severity
- Moderate · Fuel System
- Typical repair cost, all makes
- €5-€650
Connect a standard OBD2 adapter (Bluetooth LE on iPhone) to your Ford and Skanyx tells you what P0203 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 P0203 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 P0203.
Ford Focus
2005-2024
On EcoBoost petrol engines the cylinder 3 injector harness routes near the hot exhaust side and chafing or heat damage to the wiring is a common cause of P0203. The 1.5 and 2.0 TDCi diesels use common-rail injectors that are pricier and benefit from injector correction values after replacement, which a workshop or brand tool handles.
What causes P0203 on a Ford?
Beyond the generic causes listed on the main P0203 page, these are the patterns noted for Ford models:
Heat-damaged or chafed injector wiring on EcoBoost petrol
: Ford Focus
Common-rail injector failure on TDCi diesel
: Ford Focus
How to diagnose P0203 on a Ford with OBD2
- Read P0203 and the freeze frame with Skanyx. Note any P0303 (cylinder 3 misfire), P0267 or P0268 (cylinder 3 injector circuit low or high) and other injector codes stored at the same time
- Work out where cylinder 3 is. On a four-cylinder engine it is the third from the pulley end, next to cylinder 4 at the gearbox end. On a three-cylinder engine it is the last cylinder, at the gearbox end. On V6 and V8 engines cylinder 3 is on bank 1 whichever numbering the maker uses
- Inspect the cylinder 3 injector connector and the branch of harness feeding it. Look for a cracked latch, corrosion in the pins and insulation worn through where the loom is clipped to the engine
- If P0203 was stored together with another injector code, check the shared supply fuse, relay and ground first. Two injectors failing at the same moment is much less likely than a fault in something they share
- Measure the injector coil at its pins with the ignition off, then repeat from the ECU pin for injector 3 to include the harness. Use the specification for your engine type
- Swap injector 3 with a neighbour, cylinder 2 or 4 (cylinder 2 on a three-cylinder), clear the code and drive. If the code moves with the injector, replace it; if P0203 stays, repair the wiring or check the ECU driver
- When a direct-injection injector is removed, fit new PTFE combustion seals before refitting. On common-rail diesels the injector correction codes must match each cylinder, which needs a brand tool or a workshop
How much does P0203 cost to fix on a Ford? (EUR)
Estimated repair costs for P0203 in EUR, compiled across makes. Ford costs typically sit in the middle of each range.
| Repair | Parts Cost | Labor Cost | Total Estimate | DIY Difficulty |
|---|---|---|---|---|
| DIY repair of the cylinder 3 connector or wiring | €5–€30 | €0–€0 | €5–€30 | Moderate |
| Cylinder 3 circuit traced and repaired at a workshop | €5–€40 | €60–€180 | €65–€220 | Professional |
| Cylinder 3 petrol injector replaced at a workshop | €40–€150 | €60–€160 | €100–€310 | Moderate |
| Cylinder 3 common-rail diesel injector replaced at a workshop | €150–€400 | €100–€250 | €250–€650 | Professional |
Prices estimated as of October 2026. Costs vary by region, vehicle, and shop.
Codes related to P0203
These codes are often seen alongside P0203 or point to related issues, on any make:
Looking for the full P0203 reference (all makes, full diagnosis flow, complete repair cost matrix)? See the main P0203 guide