Whirlpool WMH73521CS6

Microwave · 5 documented failures, each with the part, the price, the video and the manual page.

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Owner's manual: Whirlpool's official Owner Center supports the WMH73521CS over-the-range microwave family; the stored repair model is revision 6.

What is it doing?

Documented failures

Control board

Technician only Vendor replaces this part if the microwave will not work at all
Stop. STOP. Licensed technician only.
Try this first — it costs nothing. Test the outlet with a different appliance, and check the breaker, before assuming the board has failed.

Check, in this order

  1. Rule out the outlet, the fuse, and a simple breaker trip first — all are cheaper and all present as a completely dead unit.
  2. Note whether the display is fully dark or shows a frozen/garbled readout — that distinction matters to a technician.

Before you open anything

Filmed on this exact machine
Whirlpool Microwave Oven/Hood Combo Control Board Assembly Replacement W10893407RepairClinic.com · 2:58

Parts exist for this component and are deliberately not listed here: this is not a repair to attempt yourself.

Worth fixing? Replace - this part costs as much as a new machine. Part $148.00 against $140.99 for a new machine (105.0%).Part cost only. A service call adds a regional diagnostic fee plus labour.

Door switch

Technician only Vendor replaces this part if it is damaged or missing
Stop. DIY once unplugged and once a multimeter confirms which switch failed. If reaching the switch bank means opening the inner cabinet shell rather than a simple access panel, stop and call a technician instead.
Try this first — it costs nothing. Wipe down the latch hooks and strike plate — food residue there stops the door seating fully and mimics a bad switch.

Check, in this order

  1. Confirm the door closes firmly and the latch hooks aren't bent before blaming a switch.
  2. Test each switch for continuity in and out of the door-closed position — most microwaves have two or three separate door switches and only one may have failed.
  3. Listen for a click as the door closes; a switch that doesn't click is the one to replace first.

Before you open anything

Filmed on this exact machine
Whirlpool Microwave Oven/Hood Combo Upper Right Door Switch Replacement W10269458RepairClinic.com · 3:30

Parts exist for this component and are deliberately not listed here: this is not a repair to attempt yourself.

Worth fixing? Weigh it - this part is a meaningful share of a new machine. Part $4.04–$48.81 against $140.99 for a new machine (34.6%).Part cost only. A service call adds a regional diagnostic fee plus labour.

Fuse

Technician only Vendor replaces this part if the microwave will not cook properly
Stop. STOP. Licensed technician only.
Try this first — it costs nothing. Test the outlet and breaker before assuming the fuse itself is blown.

Check, in this order

  1. Test the outlet with another appliance first — a dead outlet or tripped breaker looks identical to a blown fuse.
  2. Note whether the failure followed a pop or smell, which points at a diode or short rather than a simple overload.

Before you open anything

Filmed on this exact machine
Whirlpool Microwave Oven/Hood Combo Line Fuse Replacement W10138793RepairClinic.com · 2:37

Parts exist for this component and are deliberately not listed here: this is not a repair to attempt yourself.

Worth fixing? Weigh it - this part is a meaningful share of a new machine. Part $4.65–$50.75 against $140.99 for a new machine (36.0%).Part cost only. A service call adds a regional diagnostic fee plus labour.

Led light

Technician only Vendor replaces this part if the cabinet light will not work
Stop. DIY on models with an external or cavity-accessible light housing. If the LED module is only reachable by removing the outer cabinet, stop and call a technician instead.
Try this first — it costs nothing. Nothing free here — a dead LED module needs replacing.

Check, in this order

  1. Confirm it's the LED module and not just a loose connector by checking whether the cavity stays dark during a cook cycle too, not only with the door open.

Before you open anything

Filmed on this exact machine
Whirlpool Microwave Oven/Hood Combo Cabinet Light Socket Replacement Part W10210871RepairClinic.com · 2:40

Parts exist for this component and are deliberately not listed here: this is not a repair to attempt yourself.

Worth fixing? Weigh it - this part is a meaningful share of a new machine. Part $4.56–$21.55 against $140.99 for a new machine (15.3%).Part cost only. A service call adds a regional diagnostic fee plus labour.

Thermostat

Technician only Vendor replaces this part if the microwave will not work at all
Stop. STOP. Licensed technician only.

Check, in this order

  1. Note whether it cuts out mid-cook or refuses to reach temperature at all — both point here but mean different things to a technician.

Before you open anything

Filmed on this exact machine
Whirlpool Microwave Oven/Hood Combo Magnetron Thermostat Replacement W10598693RepairClinic.com · 8:45

Parts exist for this component and are deliberately not listed here: this is not a repair to attempt yourself.

Worth fixing? Weigh it - this part is a meaningful share of a new machine. Part $23.99–$47.24 against $140.99 for a new machine (33.5%).Part cost only. A service call adds a regional diagnostic fee plus labour.

If you replace it instead

Configuration-matched to this machine (30, ~2.1 cu ft). Prices are UPC-verified Amazon listings, not estimates. Like-for-like replacement rarely pays for itself on energy alone — replace for fit and features, or because the repair maths above says so.

ModelCapacityEnergy costPricePrice checked
Whirlpool WMH53521HZ2.1 cu ft9 Aug 2026See it
A candidate must match this machine's configuration (style, fuel and defrost class) before price or efficiency is considered. Prices are a snapshot from the date shown; availability is not monitored — check the retailer before buying.