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 7NJ. We return it repaired. Call 0203 489 2610.
Send Your Unit Today
The Vehicle Check | Unit 8 25 Mollison Avenue | Mollison Avenue | Enfield | EN3 7NJ
📞 0203 489 2610 | 📧 info@thevehiclecheck.co.uk
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