Honda Jazz ECU Cylinder 1 Misfire P0301 — Repair Specialist | The Vehicle Check
A Honda Jazz storing P0301 with a confirmed cylinder 1 misfire that does not resolve after spark plug and coil service is almost certainly an ECU driver fault. The Vehicle Check bench tests Honda Jazz ECUs, identifies whether the cylinder 1 ignition driver, injector driver or both have failed, and repairs the exact component at board level. Your original ECU returns repaired and vehicle-coded — no reprogramming required on refitting.
Confirming the Fault is in the ECU
The standard diagnostic approach is to swap the coil and plug from cylinder 1 to another cylinder and recheck. If the misfire stays on cylinder 1, the ECU is not sending the correct signal to that cylinder. Similarly, swapping the injector from cylinder 1 and seeing the misfire remain on cylinder 1 confirms the injector driver in the ECU is the cause.
Our bench test applies varying load conditions to the ECU and monitors all four cylinder 1 driver outputs — we capture intermittent driver failures that only occur under hot or loaded conditions.
Driver Replacement and Full Retest
We replace the failed MOSFET or driver IC on the cylinder 1 circuit, run a four-cylinder output test under load and return the ECU with a repair report confirming cylinder 1 is operating correctly.
Your original ECU's immobiliser data is preserved throughout — it refits and starts first time.
Post Your ECU to Us
Send your Honda Jazz ECU to The Vehicle Check, Enfield EN3 7PH. We return it repaired in 2 to 3 working days. Call 0203 489 2610.
Send Your Unit Today
The Vehicle Check | Unit 8 Solway Business Centre | Tysoe Street | Enfield | EN3 7PH
📞 0203 489 2610 | 📧 info@thevehiclecheck.co.uk
Nationwide mail-in postal service. All work covered by our repair warranty.