Jump to content
Appliance Offers
JeffSparks

Hotpoint WDL540 washer/drier is playing up

Recommended Posts

I have Hotpoint WDL540 G (UK) C washer/drier which is very ill. The only functions it will perform is to pump out, operate the door lock, and the filling solenoid. When filling, it does this in a sequence of short bursts, then nothing. I have done resistance checks on the motor, heater, and sensors, and all seem OK. I have tried running with pressure sensor pipe disconnected (it is not blocked), and with the sensor connector removed. In desperation, I have replaced the main control module, but without success. There are no fault indications on the lights on the front panel. I am an experienced electronics engineer, so I should have sorted this by now, but am at a loss to know what to do next. Could it be the front panel unit is the problem?

Share this post


Link to post
Share on other sites

Book washing machine & appliance repairs Buy appliance spare parts

Note: The links above are needed to help keep this site running, please consider using them.

Make sure there are no low insulation fault with electricity leaking to earth. That can cause strange behaviour - but essentially it sounds like the fault is that the motor isn't running. That can have multiple causes ranging from simple to complex. The most common cause especially on Hotpoint washing machines is worn carbon brushes. I have all the possible causes listed in this article - Washing machine drum not turning


Need an engineer, or to buy appliance spare parts? Please use my affiliate links to support this forum.

Book appliance engineer | Buy your Spares (4Washerhelp)

Warning:  Read this before attempting any diy repairsNo representations or warranties are made (express or implied) as to the reliability, accuracy or completeness of advice. I can't be held liable for any loss arising directly or indirectly from the use of, or any action taken in reliance on, any information on this website, which is given free of charge and in good faith.

Share this post


Link to post
Share on other sites

Of course, insulation tests were done right at the beginning, and there are no problems with the motor.

I originally thought that the front panel PCB was only there to decode the button and knob settings, and light the leds via serial communication with the main power board. But I have now dismantled the front panel and found that the PCB contains a full-function 16bit microcontroller (MCU) with a large ROM which must hold all the washing programs. It has an I2C interface with the power module, so sensor and diagnostic information must be sent to the front panel from there, and it is the MCU on the front panel PCB which then tells the power module how to control the various components like motors and heaters.

I could kick myself for not dismantling the front panel sooner. It is now clear that commands are getting from the front panel to the power module to do things like operate the pump and water valve, but it is not receiving anything back from the power module. That is why I did not get any error codes via the leds, and why it would try to do things like fill the drum briefly 3 times and then shut down. If I can't find which component has failed on the front panel, I will have to replace it, but I don't think it is the MCU because it is responding to buttons, and controlling the leds locally in the correct way.

This information may be of interest to others that have experienced similar confusing malfunctions. 

My advice, if everything physical (motors, heaters, sensors) seems to check out OK, to suspect (replace?) the front-panel unit first, before going to the difficult and expensive job of replacing the Power Module.

  • Like 1

Share this post


Link to post
Share on other sites

It's always a gamble replacing either the main PCB or the front control panel. They are both parts that can rarely be seen to definitely faulty. Even if they can be seen to have bits burned out you can't know if other components in the machine have damaged them. There's no way to put a meter on a pcb and they come up either OK or faulty. They are normally diagnosed by process of elimination, but there's always the possibility that a weird connection or wiring fault somewhere is causing the fault - or that one or both boards need replacing. Then we have the added problem of manufacturers sending replacement pcbs out with no programming on them. You have to have specialist equipment to install the software onto them. Finally we have the high prices of them and no return policy.

Basically the pcb's are something to steer completely away from unless an engineer or extremely confident electronics engineer. Even many independent engineers don't have the equipment to program some of them because some manufacturers make it very difficult, expensive, or impossible to get them. A white goods engineer can always at least use the pcb on another machine if they fit one and find the fault hasn't cleared but a DIYer will be stuck with one.


Need an engineer, or to buy appliance spare parts? Please use my affiliate links to support this forum.

Book appliance engineer | Buy your Spares (4Washerhelp)

Warning:  Read this before attempting any diy repairsNo representations or warranties are made (express or implied) as to the reliability, accuracy or completeness of advice. I can't be held liable for any loss arising directly or indirectly from the use of, or any action taken in reliance on, any information on this website, which is given free of charge and in good faith.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...