Washing machine repairs - examples

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A page of guidance for fixing various washing machine faults.

Bosch Exxcel 1400 - Extended wash cycle

The electronic timer would count all the way do to zero from its original two hour estimate, and only complete the wash cycle and move to the rinse cycle at this point. Also of note, was that the wash never seemed to reach above ambient temperature, even when a hot wash was selected.

(sorry, no detailed pictures to accompany this one)

Initial diagnosis: failed heater element, causing program to delay until target temperature is reached - only ending when maximum time expires.

Disassembly:

  1. Isolate machined from power supply
  2. Open flap to filter access cover and emergency drain point, and remove single tor screw toward the base of the machine just under the drain point. Now slide the whole lower plastic panel to the right to free it from the lugs at the end. Unentangle the drain hose and put panel to one side.
  3. Open and remove the soap dispenser drawer (by depressing blue tab inside the drawer to enable it to be completely removed). Remove single torx screw below the drawer to the right - just above the top of the main front metal panel.
  4. Open the door, and remove the two torx screws holding the door to the machine. Lift the door hinge upward to free the door, and put it to one side.
  5. Remove the sprung wire retaining ring that runs around the edge of the larger rubber door seal
  6. prise the door seal off the front panel lip around the door opening.
  7. Undo the two torx screws at the bottom of the front metal panel.
  8. Pull the metal panel toward you at the bottom, and then allow it to drop a little. This should free the top screw tab that projects up into the soap drawer base. The front panel should now pull mostly free, and only be retained by the wires to the door catch sensor on the right hand side. Position the panel out of the way carefully to the right, trying to avoid pulling the wires.

Testing the heater:

The heater is in a pocket that sits directly under the bottom middle of the drum. There will be four sets of electrical connections to it, consisting of a spade terminal on the main heater connections left and right. An earth tag in the centre, and a pair of small wires connecting to the temperature sensor just left of centre.

BoschWMHeaterElement.jpg

  1. Disconnect the left and right spade terminals.
  2. Using a multimeter on a low resistance range, measure the resistance between the terminals. You should see approximately 25 ohms. An open circuit or resistance significantly higher or less than this indicates the heater has failed.

Removing the heater:

  1. Disconnect the earth tag, and lift the small tap at the top of the sensor connector to enable the sensor connector to be pulled free of its socket.
  2. Slacken the single nut in the centre with a 10mm socket. This is tightened to cause a rubber plug at the base of the heater to bulge and lock it in place. Slackening it should allow the rubber to relax. Give the protruding threaded section a few taps with your spanner to make sure the retention plate the compresses the rubber has moved back. The heater can now be prised free. Withdraw the heater from its slot.
  3. Once free, pull the temperature sensor from its socket in the front of the heater (its a fairly tight fit).

Replacement:

  1. First test the resistance of the new element to verify it is ok (see above)
  2. Push the temperature sensor module into the new heater, so that it is flush with the front surface.
  3. Carefully wipe around the periphery of the hole where the heater is mounted, to clear any hard water scale or other debris that may make sealing less effective
  4. Feed the new element back into the machine, and push it home so that it is snugly fitted against the front panel of the drum enclosure. If its difficult to fit, then wipe a small amount of washing up liquid around the rubber seal to lubricate it.
  5. Tighten the retaining nut, and check the heater is now held firmly in place
  6. Reconnect the three spade terminals and the temperature sensor connector.

Reassembly:

  1. Replace the front metal panel, sliding the top tab up into its gap under the soap tray. When it is tight against the top plastic moulding push the base toward the machine. It should locate on a couple of lugs. Replace the two bottom screw and one top screw that secure it.
  2. Hook the bottom plastic panel onto its lugs and slide to the left. Replace the single screw that secures it. Tuck the drain hose back into its rest position. Replace the pump cover flap.
  3. Replace the soap drawer
  4. Carefully tuck the rubber door seal onto the lip of the metal case front all the way around so that it sites snugly against the case front. Replace the sprung wire retaining ring when done.
  5. Rehang the door, and secure with the screws top and bottom of the hinge.

Now do a test wash, and confirm normal operation. (remember that a hot wash will have a cold section at the start of it where the waster and detergent are allowed to work on the clothes before the heated part of the wash)

Bosch Exxcel 1400 - Drum not turning

In this case the machine appeared to be going through all the expected phases of the cycle - filling and draining, and with various clicks from the programmer as expected. Only the drum was not turning. Listening to the machine suggested there was no motor noise, which eliminated the first possible cause of a broken or dislocated drive belt. Given the machine was at least 5 years old and in constant use, the most common cause for this kind of failure is worn out motor brushes.

Inspection

The simplest way to check, is to inspect he existing brushes. First isolate the machine from the electrical supply, and remove the back cover (two sizes of torx screws). While it is in theory possible to get at the brushes with the motor on the machine, its much quicker and easier to simply remove the motor. First remove the drive belt by turning the drum by hand and pushing the belt off the runner. Next, unplug the wiring connector from the motor (one multi connector block and a separate earth tag). Remove the two securing bolts. Wiggle and pull the motor free of its mounting bushes. If it does not want to shift, insert a flat bladed screwdriver into the gap between motor and bush to get it moving.

With the motor now free and on a worktop, pull the spade connector free of each brush terminal. To remove the brush, not that the brass connection tag is free to slide a little in the recess. First slide it further into the recess such that the notches in the tag near the connections space line up with the edge of the recess. This allows the spade end to be pulled up and free. The other end of the brush terminal can now be slid free of its retaining slot.

Replacement

New brushes are around 4cm in length and are readily available for this machine (the same ones are used in many different motors). Price will vary but can usually be found from around £8 with online parts places, to perhaps £13 at retail outlets.

A worn brush may well be under 1cm. Replace both brushes at the same time, and ensure that you orient them correctly so that the slope on the end matches the original brush installation. (note the channels that the brushes slide in are angled so that the meet the commutator in the motor slightly obliquely). To fit the new brush, slide it fully into its slot, and then feed in all the spare spring. Finally locate the terminal tag back into its recess in the top of the brush slot.

Reassembly and test

Reconnect the wires to the brush terminals. Refit the motor, and reconnect the two connectors. Refit the drive belt and the back panel. The machine can now be tested. If it runs then no further work is needed. Note the machine may make slightly more noise for the first few washes as the new brushes "bed in".

There is a very good video of the process here.