A replacement transistor can place a different demand on its gate driver. A circuit that switches acceptably with the original device may behave differently with an apparently similar substitute.

What to check next

Review the replacement choice and compare the gate waveform with the intended switching conditions. Check driver supply and surrounding components before blaming the new transistor. Excess heat after repair deserves investigation even if the output still operates.

Useful information for an enquiry

Include the original and replacement part numbers and the conditions that cause heating.

Gate-drive assessment requires suitable measurement technique. Do not probe a switching node using an unsuitable ground connection or instrument rating.

Speak to AXION

For ECU testing and component-level repair, send your vehicle details and fault report. Workshop assessment is in Didcot, Oxfordshire. Suitable postal or remote work is confirmed before booking.

Technical background from Nexperia. The referenced design explains the principle; the vehicle-specific procedure determines the repair.

Related reading — MOSFET body-diode behaviour in a motor-control repair. Browse all vehicle-electronics diagnostic notes or return to the repair library.