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Whirlpool
Countertop Microwave

Model # MT4078SPB4 Official Whirlpool compact microwave

Here are the diagrams and repair parts for Official Whirlpool MT4078SPB4 compact microwave, as well as links to manuals and error code tables, if available.

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Installation guide
Owner’s manual

Model diagram and schematic

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Showing 10 of 57 parts  |
Microwave High-voltage Diode 8205489
#8

Oven interior parts diagram

Microwave high-voltage diode

Part #8205489

Replaced by #WP8205489

?
Manufacturer substitution
This part replaces 8205489. Substitute parts can look different from the original.
$32.49 | 
16% OFF Phone Price : $38.49
In Stock
Screw 4358362
#10

Oven cavity parts diagram

Screw

Part #4358362

Replaced by #W11245710

?
Manufacturer substitution
This part replaces 4358362. Substitute parts can look different from the original.
This item is not returnable
$16.79 | 
11% OFF Phone Price : $18.79
In Stock
Fan Blade 8184292
#1

Oven interior parts diagram

Fan blade

Part #8184292

$36.16
In Stock
Transformer W10329445
#4

Base plate parts diagram

Transformer

Part #W10329445

$175.38
In Stock
Switch 8183562
#4

Latch board parts diagram

Switch

Part #8183562

Replaced by #4392027

?
Manufacturer substitution
This part replaces 8183562. Substitute parts can look different from the original.
$69.11 | 
8% OFF Phone Price : $75.11
In Stock
Microwave Screw 4358489
#18

Oven interior parts diagram

Microwave screw

Part #4358489

Replaced by #4344826

?
Manufacturer substitution
This part replaces 4358489. Substitute parts can look different from the original.
$12.49
In Stock
Capacitor W10246258
#4

Oven interior parts diagram

Capacitor

Part #W10246258

Replaced by #W10293696

?
Manufacturer substitution
This part replaces W10246258. Substitute parts can look different from the original.
$107.60
In Stock
Switch 8183561
#3

Latch board parts diagram

Switch

Part #8183561

Replaced by #4392027

?
Manufacturer substitution
This part replaces 8183561. Substitute parts can look different from the original.
$69.11 | 
8% OFF Phone Price : $75.11
In Stock
Screw 4358192
#6

Base plate parts diagram

Screw

Part #4358192

Replaced by #W11380570

?
Manufacturer substitution
This part replaces 4358192. Substitute parts can look different from the original.
This item is not returnable
$18.19 | 
10% OFF Phone Price : $20.19
In Stock
Turntable Motor 8184375
#8

Oven cavity parts diagram

Turntable motor

Part #8184375

The manufacturer no longer makes this part, and there's no substitute part

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