How to replace a washing machine control module

One of the most frustrating problems with washing machines is a failure of the main control module. The electronic control unit is the "brain" of the washing machine. It controls all processes, from water intake to drainage and spinning. If the control board is damaged, the machine will not be able to complete a wash.

Replacing a washing machine's control module is not an easy task. It's important to proceed with extreme caution to avoid further damage to the appliance. We'll show you how to install a new control module yourself.

When should the SMA electronic brain be changed?

First, you need to make sure the problem is truly with the control unit. Sometimes, the illusion of a faulty control unit is created by another faulty part of the washing machine. This is crucial, because if the problem lies elsewhere, replacing the board won't solve the problem, and your money will be wasted.

You can suspect microcontroller damage by the washing machine's behavior. This malfunction has characteristic signs. Let's look at the situations in which it might be a good idea to check the electronic unit.

• The washing machine won't spin, and the control panel freezes and stops responding to button presses. No error code appears on the display.
• The indicator on the dashboard flashes randomly, and it is impossible to select and start the washing algorithm.
• The machine allows you to select a mode and start a cycle, but the process stops there. It either doesn't fill with water at all, or all the water immediately goes down the drain. After a few minutes, the washing machine freezes and only recovers after a reboot. Upon restart, the wash cycle will likely proceed as normal.
• The washing machine, regardless of the selected mode, runs for 3-4 hours without spinning or draining. The pump doesn't even attempt to remove water from the system. After a while, the machine freezes.
• After starting the washing machine and trying to select the desired washing mode using the programmer, the device freezes and turns off.
• The engine changes the drum speed at its own discretion.
• The heating element ignores the temperature sensor commands and cannot heat the water to the set temperature, leaving it either cold or boiling.

If the washing machine cannot correctly perform the washing algorithm, freezes during the cycle, or turns off by itself, this is a reason to check the functionality of the control module.

Each of the symptoms described could indicate either a faulty circuit board or a faulty sensor. For example, a faulty heating element or thermistor could be the cause of the water not reaching the desired temperature. A faulty pressure switch could also be the cause of the water leaking. Before attempting to replace the control module, be sure to perform a comprehensive diagnosis of the washing machine.

Let's run a self-test of the machine

Modern automatic washing machines can help identify faults. They have a self-diagnosis system that needs to be activated. After completing the test mode, the machine will display an error code indicating the problem area. How do I initiate the self-diagnosis?

The self-diagnostic system is activated differently on all machines; information on how to enter service mode is provided in the user manual.

Some models have a special button on the control panel that, when pressed, initiates a self-diagnosis. This is the easiest way to activate test mode. On Ardo washing machines, the self-diagnosis is activated as follows:

• the programmer knob is turned to a vertical position, with the arrow pointing downwards;
• the temperature is set to zero;
• all buttons on the control panel are pressed at once.

Running a service test on many Indesit models is done as follows:

• the program selector is set to position 1, the machine is turned on;
• the programmer is moved to position 2, the washing machine is turned off;
• the selector returns to the first position, the “ON” button is pressed again;
• the program selector knob is set to position 3, the washing machine is turned off;
• the programmer turns back to the first position;
• the start key is pressed;
• the switch is turned to "Drain".

After running the automatic test, you'll have to wait. The machine will begin performing each stage of the cycle, one after another: filling with water, spinning the drum, etc. This is necessary to identify the point at which the problem occurs. During the service test, the washing machine will display a fault code corresponding to the problem. You can decipher the error using the washing machine instructions.

If the error code reads "heating element failure," there's no point in messing with the machine's internals. A new heating element will suffice. However, if the machine specifically indicates a problem with the control module, repairing the controller is inevitable.

The self-diagnostic system doesn't always indicate a specific problem. Sometimes the error code indicates completely different issues, such as a damaged fill valve, broken wiring, or a faulty module. In these cases, each component is checked manually.

The control module is checked with a special device – a multimeter.

All other "suspicious" components are also tested with an ohmmeter. The device can measure the resistance between contacts and check for breakdown. This manual diagnostic allows for a 100% accurate identification of the problem.

Replacing the control module

In some cases, the control board can be repaired, but experts typically recommend replacing the entire module. In the vast majority of front-loading automatic washing machines, the electronic unit is located behind the dashboard. It's quite large, so it's hard to miss the controller.

To save time searching, consult the instructions. They'll tell you exactly where the control board is located. To remove the module, follow these steps:

• de-energize the washing machine;
• turn off the valve that supplies water to the system;
• disconnect the machine from communications;
• remove the top panel of the case by unscrewing the bolts holding it and unfastening the latches;
• take out the detergent drawer;
• remove the bolts located near the powder receptacle;
• unscrew the screws securing the instrument panel;
• carefully remove the control panel without touching the wires;
• capture the wiring diagram on a photo;
• disconnect the wire bundle from the control panel and move the instrument panel to the side;
• unscrew the bolts holding the control board;
• remove the control module from the washing machine housing.

Afterwards, carefully inspect the controller for damage. This could include traces of carbon deposits, mechanical defects, or rust. In some cases, the board can be restored by replacing the semiconductor or re-soldering the track. However, repairs are often more time-consuming and expensive, so it's easier to replace the unit with a new one.

If your washing machine is still under warranty, don't attempt any diagnostics or repairs yourself. Leave this to a service center. Once your free service period has expired, you can try repairing the washing machine at home.

The new control module is installed using the same procedure, in reverse order. The controller is secured to the machine with bolts, and the wiring is connected (refer to the photos taken during disassembly for connecting the connectors). Then, the instrument panel, powder receptacle, and top cover are reinstalled.

After reassembling the machine, test its functionality. Plug the machine in and run an empty cycle. The problem should be resolved. If the machine completes the cycle normally, the control module replacement was successful.

   

1 reader comment

1. September 14, 2023, at 11:47 PM

   Volodya:

   Haier hw60. The front control module shorted out. I replaced it with a new one. Even the power supply doesn't work. What's the cause?

   Answer