Whirlpool
Countertop Microwave

Model #MT4078SPB1 Official Whirlpool countertop microwave

Here are the diagrams and repair parts for Whirlpool MT4078SPB1 countertop microwave, as well as links to manuals and error code tables, if available.

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For DIY troubleshooting advice and repair guides, visit our repair help section.

Showing 10 of 56 parts

Fan Blade#1

Oven interior parts Diagram

Fan blade

Part #8184292
In Stock
$36.16
Microwave Door Primary Interlock Switch#3

Latch board parts Diagram

Switch

Part #8184285
Replaced by #4392027
?
Manufacturer substitution
This part replaces 8184285. Substitute parts can look different from the original.
In Stock
$69.11 | 
20% OFF 
MSRP: $86.00
Microwave Screw#14

Oven cavity parts Diagram

Screw

Part #4358188
Replaced by #WP4158079
?
Manufacturer substitution
This part replaces 4358188. Substitute parts can look different from the original.
This item is not returnable
In Stock
$2.16
Microwave High-Voltage Diode#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.
In Stock
$30.69 | 
14% OFF 
Phone Price: $35.69
Microwave Door Primary Interlock Switch#4

Latch board parts Diagram

Switch

Part #8184286
Replaced by #4392027
?
Manufacturer substitution
This part replaces 8184286. Substitute parts can look different from the original.
In Stock
$69.11 | 
20% OFF 
MSRP: $86.00
Control#6

Control panel parts Diagram

Electronic control

Part #8205473
Replaced by #WP8205473
?
Manufacturer substitution
This part replaces 8205473. Substitute parts can look different from the original.
In Stock
$260.49
Microwave Screw (replaces 4358380, R0654041)

See All Related Diagrams

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
In Stock
$18.19 | 
10% OFF 
Phone Price: $20.19
SCREW

See All Related Diagrams

Microwave screw

Part #4358489
Replaced by #4344826
?
Manufacturer substitution
This part replaces 4358489. Substitute parts can look different from the original.
In Stock
$12.49
Microwave Screw#10

Control panel parts Diagram

Screw

Part #4358883
Replaced by #WP4158079
?
Manufacturer substitution
This part replaces 4358883. Substitute parts can look different from the original.
This item is not returnable
In Stock
$2.16
Turntable Motor#11

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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