Maytag MHWC7500YW0 User Manual

FOR SERVICE TECHNICIAN ONLY - DO NOT REMOVE OR DESTROY
PART NO. W10468733A PAGE 1
IMPORTANT
Electrostatic Discharge (ESD)
Sensitive Electronics
ESD problems are present everywhere. ESD may damage
or weaken the electronic control assembly. The new control
assembly may appear to work well after repair is finished,
but failure may occur at a later date due to ESD stress.
■
Use an anti-static wrist strap. Connect wrist strap to green
ground connection point or unpainted metal in the appliance.
-OR-
Touch your finger repeatedly to a green ground connection point
or unpainted metal in the appliance.
■
Before removing the part from its package, touch the anti-
static bag to a green ground connection point or unpainted
metal in the appliance.
■
Avoid touching electronic parts or terminal contacts; handle
electronic control assembly by edges only.
■
When repackaging failed electronic control assembly in anti-
static bag, observe above instructions.
D
IAGNOSTIC GUIDE
Before servicing, check the following:
• Make sure there is power at the wall outlet.
• Has a household fuse blown or circuit breaker tripped? Time
delay fuse?
•
Are both hot and cold water faucets open and water supply
hoses unobstructed?
• All tests/checks should be made with a VOM or DVM having
a sensitivity of 20,000 ohms per volt DC or greater.
• Check all connections before replacing components. Look for
b
roken or loose wires, failed terminals, or wires not pressed into
connections far enough.
• A potential cause of a control not functioning is corrosion on
connections. Observe connections and check for continuity
with an ohmmeter.
• Connectors: Look at top of connector. Check for broken or loose
wires. Check for wires not pressed into connector far enough to
engage metal barbs.
• Resistance checks must be made with power cord unplugged
from outlet, and with wiring harness or connectors disconnected.
POSSIBLE CAUSE/TEST
PROBLEM NOTE: Possible Cause/Tests must be performed in the sequence shown for each problem.
WON’T POWER UP 1. Check that the washer is plugged into a working outlet and for blown fuses.
(buttons do not respond 2. Check for power going to Central Control Unit (CCU) by listening for a click in the CCU
when pressed) when the washer is plugged in. If no click, replace the CCU.
3. Unplug washer or disconnect power.
4. Check continuity of line cord and line filter.
5. Check harness connections to the CCU.
6. Plug in washer or reconnect power.
7. Check the button/LED assembly by selecting different cycles and changing the modifiers
and options available to confirm that the button/LED assembly is responding.
8. Check the connection of the power cord to the line filter and at the CCU. Check to confirm
that the door closes fully.
WON’T START CYCLE 1. Open and close the door. The door must be opened between consecutive wash cycles.
2. Check the door switch/lock unit using the diagnostics. See Quick Diagnostic Test.
3. If door is locked, drain the washer.
4. Unplug washer or disconnect power.
5. Check the wire harness connections.
6. Plug in washer or reconnect power.
7. Check the button/LED assembly by selecting different cycles and changing the modifiers
and options available to confirm that the button/LED assembly is responding.
TROUBLESHOOTING GUIDE
NOTE: After problem(s) are fixed, please run the diagnostic test to ensure that there are no other issues.

Maytag MHWC7500YW0 Specifications

General

Brand	Maytag
Model Number	MHWC7500YW0
Product Type	Washer
Color	White
Capacity	4.7 cu. ft.
Agitator	Yes
Wash Cycles	10
Temperature Settings	5
Control Type	Electronic
Energy Star Certified	Yes
Steam Function	No
Sanitize Cycle	Yes
Width	27 inches
Depth	27 in.
Height	43 in

Summary

Safety and Handling Precautions

Electrical Shock Hazard Warning

Warning to disconnect power before servicing to avoid death or shock.

Electrostatic Discharge (ESD) Precautions

Guidelines for handling ESD-sensitive electronics to prevent damage.

Troubleshooting Guide

Won't Power Up

Steps to diagnose why the washer buttons do not respond when pressed.

Won't Start Cycle

Steps to diagnose why the washer fails to start the selected cycle.

Won't Shut Off

Troubleshooting steps when the washer does not stop running.

Control Won't Accept Selections

Steps to diagnose when the washer control panel is unresponsive.

Won't Dispense

Troubleshooting steps when the washer fails to dispense detergent or fabric softener.

Won't Fill

Steps to diagnose why the washer is not filling with water.

Overfills

Troubleshooting steps when the washer fills with too much water.

Drum Won't Rotate

Steps to diagnose why the washer drum is not spinning or rotating.

Motor Overheats

Troubleshooting steps when the drive motor becomes excessively hot.

Won't Drain

Steps to diagnose why the washer is not draining water.

Washer Vibrates

Troubleshooting steps when the washer experiences excessive vibration.

Incorrect Water Temperature

Steps to diagnose issues with incorrect water temperature during cycles.

Display Flashing

Troubleshooting steps related to flashing error codes or indicators on the display.

Diagnostic Test Procedures

Starting Universal Test Mode

Procedure to initiate the Universal Diagnostic Test mode.

Universal Diagnostics Test Details

Diagnostic Test Codes

Explanation of indications, control actions, and failure codes during the diagnostic test.

Quick Diagnostic Test Procedures

Starting Quick Test Mode

Procedure to initiate the Quick Diagnostic Test mode.

Component Testing and Identification

Central Control Unit (CCU) Connector Location

Diagram and identification of connectors for the CCU.

External Component Electrical Ratings

Details on electrical ratings, resistance, wire color, and signals for various components.

Line Filter

Information and testing guidelines for the line filter component.

Motor Continuity Test

Procedure to test motor continuity and resistance values.

Water Temperature Sensor Testing

Procedure to test the water temperature sensor and its resistance at different temperatures.

Water Valve Specifications

Details on water valve voltage, status, and nominal resistance.

Electronic Assemblies Removal and Replacement

Central Control Unit (CCU) Removal

Step-by-step instructions for removing and reassembling the CCU.

LED Assembly Removal

Procedure for removing the LED assembly from the control panel.

Motor Control Unit (MCU) Removal

Instructions for removing the Motor Control Unit (MCU).

Display Failure and Error Codes

Error Code 809: No Water Detected

Explanation and procedure for error code 809 related to water fill issues.

Error Code A10: Long Drain

Explanation and procedure for error code A10 related to excessive drain time.

Error Code F01: No Water Detected

Explanation and procedure for error code F01 related to water fill issues.

Error Code F02: Overflow Condition

Explanation and procedure for error code F02 related to overflow issues.

Error Code F03: Long Drain

Explanation and procedure for error code F03 related to excessive drain time.

Error Code F05: Water Temperature Sensor Error

Explanation and procedure for error code F05 related to water temperature sensor faults.

Error Code F06: Drive Motor Tachometer Error

Explanation and procedure for error code F06 related to motor speed detection faults.

Error Code F07: Motor Overspeed

Explanation and procedure for error code F07 related to motor overspeed conditions.

Error Code F13: Door Lock Error

Explanation and procedure for error code F13 related to door lock failures.

Error Code F14: EEPROM Error

Explanation and procedure for error code F14 related to EEPROM communication faults.

Error Code F21: Serial Communication Error

Explanation and procedure for error code F21 related to serial communication faults.

Error Code F22: Load Detected During Clean Washer Cycle

Explanation and procedure for error code F22 related to load detection.

Error Code F23: Pressure Switch Error

Explanation and procedure for error code F23 related to pressure switch faults.

Error Code F24: Valve Leakage/Overflow Failure

Explanation and procedure for error code F24 related to valve leakage or overflow.

Error Code F26: Pump Drive System Error

Explanation and procedure for error code F26 related to pump drive system faults.

Error Code F27: Motor Control Unit Error

Explanation and procedure for error code F27 related to motor control unit errors.

Error Code F28: Motor Control Unit Error

Explanation and procedure for error code F28 related to motor control unit errors.

Error Code F29: Door Switch Error

Explanation and procedure for error code F29 related to door switch failures.

Error Code F30: Door Lock Broken / Door Switch Error

Explanation and procedure for error code F30 related to door lock or switch failures.

Error Code Fod: Suds Lock

Explanation and procedure for error code Fod related to suds lock or detergent overdose.

Wiring Diagram