Parts for R4A78 — Sharp Microwave

We found 44 parts confirmed to fit the Sharp Microwave R4A78.

Compatibility table

Prices shown are an informational reference range only, not an offer or an Amazon price — RepairKitHub does not sell parts directly. Each part links to an Amazon search so you can compare current listings yourself.

Common failure areas on this model

The confirmed parts above group into a handful of failure areas. Here is what each points to and how to check it before you order anything.

General hardware and mounting parts

Symptom: A small mechanical or mounting part has failed, cracked, or gone missing.

Check: Compare the physical shape and mounting points to the original piece, and confirm the exact part number against your model plate before ordering.

Parts in this group on R-4A78: 90006ZY3000 (Bolt), 00967006 (CABLE TIE- .), DB9202875A (PCB Subassembly), RHIZA700DRE0 (I.c.), 468615513 (Emerson Zener Hz4a2), QFSHDB003MRE0 (Fuse Holder), FROLPB018MRK0 (T/table), VSKRA101M3 (TRANSISTOR (), 461780953 (Alarm), RALMA014DRE0 (Buzzer), 12664FTKIT (Microwave Magnetron), 4617123773 (Oven Lamp Socket), 4616264043 (Microwave Door Interlock Switch and Fuse), PPACGB014MRF0 (Packing), LBNDKB007MRP0 (HVC BAND), 461770113 (Latch), PDUCB042MRP0 (Magnetron), QFSTB006MRE0 (Thermal Cu), RRLYA094DRE0 (Relay), NFANPB001MRE0 (Fan Blade), QSOCLB006MRE0 (Lamp Socket), 551009112 (Shop Vacuum Dust Bag), AJP73594505 (Kenmore Elite Refrigerator Freezer Drawer Assembly AJP73594505), FHDZB008MRY0 (Diode), QSWMA110WRE0 (Switch), LSTPPB021MRF0 (Latch), FFSBA016KIT (MONITOR SWIT), 647042710637 (MTD Lawn Mower Grass Bag Frame).

Storage, trim and cosmetic hardware

Symptom: A cracked shelf, broken door bin, worn hinge, or missing trim piece -- cosmetic and storage wear rather than a functional breakdown.

Check: Match the physical dimensions and mounting tabs of the old part before ordering; these pieces are often model-specific even between visually similar models.

Parts in this group on R-4A78: 201417GS (FITTING), 1412855T97100 (Home Electronics Coil Spring), XCPSD30P08000 (Screw), MSPRTA050WRE0 (Spring), MSPRTA046WRE0 (LATCH SPRING), 134999525 (Washer Door Outer Panel), DE6402629A (Microwave Vent Grille), 8183851 (Vent Grille - Black).

Controls, timers and wiring

Symptom: A cycle that doesn't advance, an unresponsive display, or the unit not starting at all.

Check: Look for burn marks or a burnt smell near the board or terminals, and check whether buttons and knobs respond -- a unit that powers on but won't cycle often traces back to this group.

Parts in this group on R-4A78: 0220754401 (Home Electronics Capacitor), 462014893 (Goldstar Television Capacitor, 25-volt, 0.01-mfd), VCEAB31VW477M (Capacitor), VCEAB31VW106M (Home Electronics Capacitor), VCKYB11EX103N (CAPACITOR), W11179310 (Electric Control Board).

Interior lighting

Symptom: The interior light doesn't turn on when the door opens.

Check: Confirm power is reaching the socket, then check the door-activated light switch before assuming the bulb itself is at fault.

Parts in this group on R-4A78: STD372151 (Light Bulb, T-7, 15-watt).

Door, lid switches and latches

Symptom: The appliance won't start, or stops, unless the lid or door is fully latched shut.

Check: Listen for an audible click when the lid or door closes. No click, or a visibly cracked plastic tab on the latch, points to this part.

Parts in this group on R-4A78: 501751 (Microwave Door Latch Spring).

Before you buy

Match R4A78 exactly against the model and serial plate on the appliance itself before ordering anything — a single mismatched character can point to a different production run with different parts. Then check the part number printed or stamped on the part you are replacing against the part numbers in the table above; the printed number is the most reliable way to confirm fitment when a model has gone through multiple production runs. RepairKitHub does not sell parts directly — every part link above routes to an Amazon search for that part number so you can compare current listings and sellers yourself.

How to confirm this is your model

On most microwaves, the model and serial plate sits inside the door frame. Match every character exactly, including letters and dashes at the end — appliance model numbers often have similar prefixes but different suffixes for different production runs.

Neighbouring Sharp Microwave models

These model numbers sort next to this one in the catalog and are usually the same product family.

• R-4A85 — 34 parts
• R-4A86 — 37 parts
• R-4A88 — 18 parts
• R-4A95 — 22 parts
• R-4A96 — 19 parts
• R-4A77 — 11 parts
• R-4A76 — 17 parts
• R-4A75 — 24 parts
• R-4A58 — 19 parts
• R-4A57 — 20 parts

Still not sure?

Use the model lookup tool to search by model or part number, or start from the symptom your appliance is showing.