Fixing the start button

Maybe I don't fully understand the "black screw" problem. When I reassembled mine I reattached the control panel assembly to the housing with all the screws, put the housing in place, pulled the control panel side of the housing out slightly and I was able to easily reach in and connect the two connectors to the board. Seems to me it would have been just as easy to do this in reverse. If I needed to do this again I would do everything the same up to the "remove the back" step in Chris Helming’s instructions, then, from here, instead of fighting with the black screws, I would:

1) Remove the one screw from the bottom of the toaster pointing up, and which holds the bottom of the control panel to the toaster chassis.

2) Detach the outer housing from the toaster chassis by gently (but firmly as it takes some force) pulling the outer housing of the toaster (plus the control panel which is attached to it) backwards, but only until it disengages from the chassis - the control panel is still connected to the toaster via ribbon and power cables!

3) You should now be able to pull the control panel side of the housing outward and be able to reach in to disconnect the two connectors which go from the control panel to the board on the toaster.

4) With the connectors disconnected, the housing + control panel can be easily removed from the rest of the toaster.

5) Now, with the housing off the toaster, you can then easily access and remove all the black screws which attach the control panel to the housing, disassemble the control panel, work on the board, etc, then reassemble in reverse order.

Thanks to Chris and Phil for the great info on how to get at the circuit board!

I checked all four switches with a multi-meter, and all but the bottom ‘frozen’ button were flaky. When pressed the resistance should be steady and near zero, but the resistance readings on the upper three when pressed bounced around and were not near zero. This leads me to believe that the problem is environment (heat and moisture) rather than mechanical wear, as I never use the F/C button and rarely the convection button. This also means that swapping switches is not likely to lead to a long-term solution. Here is a link with a bunch of switches that will work (don’t get the ones where the picture shows very long legs) : Switches from DigiKey. This one, Best switch has gold plated contacts and is made for corrosive harsh environments (It is also vastly more expensive than the others, but still only $3 each)

A couple of months our Breville BOV800XL started giving trouble. It would do the preheating but then not carry on heating at the set temperature at all. Sometimes it would work but mostly not. The START button seemed to be the problem, I thought. It would be intermittent and sometimes the fan would come on but no heat.

I took it apart and did not see anything obviously wrong. Then I re-arranged the small switches, discussed here, making sure one of those rarely used ones ended up in the START position. Still no joy, but sometimes the work-around suggested seemed to work. I decided to replace the switches and still no consistent performance. I could get it working on my workshop bench but when I put it all back together and back in the kitchen still no luck from time to time.

With the unit back on the bench and dis-assembled but with the 9 pin cable and 2 pin one connected, I noticed that if I moved the 9 pin cable near the connector on the main PCB I could get all sorts of odd behaviour when plugging the unit in, including the E5 error. I thought the cable that gets folded from the front panel to the PCB was the problem. I managed to get a few such cables cheaply (Ali-Express) and put a new one in, soldering it carefully on the control board. Astonishingly it did not solve the problem. I cut the front of the plastic on the 9 pin connector on the PCB. When I attached and then removed the connector plug I noticed a couple of the pins on the board were not at the same height and had moved slightly.

I then removed the PCB. Removing the spade connectors has to be done with long needled nosed pliers to release the connector. (You have to mark which connector goes where, especially 2 on the lower rhs of the board.) I then measured the resistance from each pin in the connector to a soldered component position on the correct metal trace on the non-component side of the board. Most of them had zero resistance but a couple a few kilo-ohm. When I measured the resistance from the solder of a problem pin to the same place on the metal trace I got zero ohms. When I looked at the solder joint of the pin on the board with a magnifying glass I found a hair line gap/crack where the base of the pin went into the solder, all around it! If you knew where to look you could hardly see it without the a magnifying glass. I re-soldered all the pins to get a good small lump of solder on each, and for good measure soldered the cable wires onto the pins of the connector, getting rid of the connector plug.

With this done I tested the unit. No problems at all, anymore! I found that if I plugged in a bench (non-dimmable) LED lamp to the same circuit as the unit, the light would flicker very slightly when the elements were on. Once the unit come up to the set temperature the elements switch on an off – it is hard to see them glow (Roast function) except in the dark. I also used a digital oven temperature probe to watch the unit maintain roughly the set temperature.

The unit gave trouble before I disassembled it so the pin problems on the PCB existed before I removed the 9 pin connector. I could have made it worse I suppose, but this is unlikely the original cause. Any good soldered joint should last for ages but when the unit has been used perhaps more than 1000 times by us, it could deteriorate since the board and the soldered connector gets hot each time the unit is used. It there is a small gap/crack that does not go all around the base of a pin the unit could work most of the time. A signal from the front control panel might be corrupted and a relay might not then work properly. Depending on which pin(s) have the problem you’d get different problems. I suspect some of the problems people have had might be related to the one I had. It is possible that with new switches the signal to the PCB board is good enough to overcome the resistance between a pin and its soldered joint to a metal trace.

So first when trouble shooting looking at the connector pins on the PCB might be a good place to start.

I nearly gave up a number of times. It was the fact that the unit worked sometimes that gave me hope. If I counted the hours I spent on this it might be embarrassing.

I was able to fix the start button issue using the great comments above. Thanks for posting them.

A few things to add that might help.

I replaced the Control PCB Assembly with a new assembly from eReplacementParts, using the link above (part number SP0010507, for $41.03). The part was backordered and took 2.5 months to arrive. The new screen is bright and the start/stop button works every time; feels like new. I did not solder.

I used both methods described above (by Chris and Phil). I used Chris’ method first. I was actually not able to fully remove the top case, only the left side of it (when looking from the back); the black screws were definitely a challenge.

Later, I read Phil’s method and decided to give it a try. For me, the top and right sides of the top case were held in very tightly, so it took a lot of wiggling and a fair bit of force, to finally pull them free. Remember to remove the screw on the bottom of the oven first. The top and right sides have a tongue-and-groove fit with the front of the oven. And, it also wasn’t the easiest thing in the world to put the tongue back in the groove when re-assembling. Note that with Phil’s method, you do not have to remove the back of the toaster oven.

Once the top case, with the control panel still attached to it, are free, and the two wires are disconnected, it’s easy to remove the black screws, as Phil says. So, having tried both methods, I would use Phil’s if I had to do it again.

One final thing. When I removed the white plastic cover from the control assembly, a spring fell out. I assumed that it fell out from the start/stop button and that’s where I put it back when re-assembling the control unit.

Changing the switches around fixed mime for awhile only: the uncontrolled pressing of the switch by kids flexes the board and does all kinds of havoc on the multiple connections.

Using a very thin tipped soldering iron, I remelted a lot of the contacts all over the board (using my best reading glasses) and even added a bit of lead in a couple of places that seemed thin. Flawless for a couple of months now. I had nothing to lose, saved me from buying a new board.

Thanks to original poster and posters suggesting better ways to get the oven apart! I just found this after fighting my pushbutton for a couple of months. On a lark I looked on DigiKey and I think I found the switch. I have ordered some and will report if they fit. The switch I ordered is ALCOSWITCH Switches 1825910-6. they are a whopping $0.10 each.

data sheet from Digikey

After at least 2 years of putting up with the switches, I finally took it apart. I removed all 4 switches and replaced them with the ones I had bought a couple years ago. The unit is now working perfectly, hopefully it stays that way as we use this thing almost everyday.

Just to second all the previous posts, the start button is a fairly easy item to replace on the PCB. I bought a bag of 100 switches from Amazon and used three of them to replace three bad switches. They worked perfectly. See the link below.

DAOKI 100Pcs 6x6x5 mm Miniature... https://www.amazon.com/dp/B01CGMP9GY?ref...

To anyone who finds this years later that has an older Breville BOV800XL/A: Besides having a few switches that were bad on my board, I also had a couple of rotary knobs that weren’t working consistently and one of them failed after I made the switch repair (likely from pulling the knobs off from disassembly). I ordered replacement control boards from 2 places online but I kept getting sent the updated board that has a 10-pin connector and different knobs. After a lot of digging I think I found the part on Mouser that seems to be a direct replacement. I couldn't figure out the specs of the original encoders but these are dimensionally accurate and seem to be working fine after soldering them in and testing for a while.

https://www.mouser.com/ProductDetail/Bou...

Part information just in case the link is ever down

Bourns 23mm Low Profile Increment-Ring Encoder

Mfr. part number: PER231-P19-N0010

So after a month or so, the original problem returned and continues to happen intermittently. I only swapped the switches so am now considering trying to replace it and change the position of that spring while I’m at it. Was wondering if Dustin Rhoades had success with the switches he ordered? Or if anyone else can tell me what switch to buy?

I’m glad to have found this thread.

I removed the front control board and powered things back up.

My BOV845 is buzzing loudly from the front temperature control knob. When i turn the knob, the buzzing changes a bit. I’m thinking that maybe it’s not the switches but the rotating (pots?). Has anyone tried to replace those? Its very weird to me that i’m hearing buzzing from them, seems to suggest a short of some sort, and a lot of current passing through!?

Great thread.

I’m having a problem with a slightly different part, it’s the rotary function dial labeled KS101 in the picture of the board that Chris posted. Any idea what part that is and where I can order it?

Thanks!

I bet Sean found the root cause. If I remember correctly, the thin white sheet insulating the circuit board from the oven heat was not there on the earlier version we had. This supports what Sean found, and that Breville tried to remedy the problem. It’s unfortunate they cannot control the manufacturing quality tight enough to get better solder joints.

The return Spring for the starting knob could contact the PC board connections and give problems. I insulated the components with plastic dip and did the same with the spring. I haven't had any problems in 2yrs.

Agree with @coleman_ that replacing the start button with a new switch is better than swapping. Actually any new press button would do. I fixed by replacing the start button and adding 104 capacitor across the new button to reduce some noise. After reading the PCB traces, it seems that Breville uses voltage devide circuit and one ADC pin to catch signals for all buttons:

VCC
   |
1kohm
   |-- ADC pin on MCU
   |
1kohm -- start button -- GND
   |
1kohm -- convection button -- GND
   |
1kohm -- other button -- GND

When different buttons are pressed, ADC will sample the voltage and get different readings, but then the start button is aged and the noise or higher resistor has caused the voltage to be mis-classified as the convection button.

That is why the workaround worked "Press and hold the convection button then press the on/off button, and lastly release the convection button".

The reason the "butter knife" workaround worked sometimes, was because the control pannel was not grounded so it has some induced voltage (which would trigger voltage tester pen).

Well, that was an irksome couple of hours! But with a new set of switches, my oven works like new.

Buying a 24” screwdriver from Harbor Freight for nine bucks was a very worthy investment for reaching those infamous black screws. I have no idea how they actually built that - I guess the control panel and case are assembled first, then the actual oven box and heating elements are slid in after?

Now I have 118 switches left over. At least 6x6mm tactile switches are plentiful - doing a board swap is currently impossible as the boards are not available from Breville or the usual aftermarket repair outfits.

Thanks for the OP and other valuable replies. My BOV845BSS started alerting sometime a couple of weeks ago, which may happen when the oven is idle or during heating. I followed the previous solution and switched the on/off button with the c/f one and resoldered some parts of the power board. After I pack the case back, perfect, but somehow the problem still exists. Then I found the issue seems related to the contact. I tried touching the pin of the on/off button and thought maybe the spring played the trick. Then wrapped the spring with the shrinking tube, and ta-da, the problem is gone. Finally, I was happy too early, THE SAME problem came back again. I do believe there are some points that need to be resoldered but couldn't figure out where to go... I am going to order a new panel anyway.

I have problems with the fresh/frozen, convection and F/C buttons all trading functions plus I have another problem that no one else has mentioned having: The temp/darkness dial doesn't work. The person I got the oven from said it will work once the oven is heated up but I haven't seen that yet.

I pulled the control PCB and reflowed the solder on the contacts of the 4 switches plus I did the same on the 5 contacts on each of the three rotary dial switches (are those mechanical encoders?). I also reflowed the 9 contacts for the ribbon cable that goes to the other PCB.

I put the board back in and tested it and nothing had changed. Still have the same issues so reflowing the solder was not the fix for any of the problems. I can order in replacements for the small switches from DigiKey. I didn't see anything on the rotary switches (encoders?) to help me identify what switch that is to see if I can find a replacement for it on Digikey. Does anybody know of a replacement for those rotary switches (encoders?) on Digikey or Mouser?

My Breville Toaster Oven (BOV800XL/A) is about ten years old and has been a great unit except the start button is finicky, especially for toast.

I have called Breville several times but they can't help. They pretend it is my problem--like I have stupid fingers

It is an inconvenient but it is too expensive to replace.

This week I am concerned because when on, it has started to make a cracking sound and it may be shorting.Nothing online or in their manual deals with this and I think it may be a fire hazard so have unplugged it.

There are no small appliance repair people around here anymore. Not worth their time.

Thanks for all the great information in this thread. My oven is presenting a novel problem that I thought might be related to a ‘bad start button’ so I gave this fix a try. Unfortunately, it's still doing the same thing, which I'll describe later, but I didn't completely break it so I'm calling it a draw.

I'm including some pictures that I think others might find helpful:

1. The solder side of the PCB. The posts for the two switches that were switched in the original instructional are circled - main power on left and temperature toggle on right.
2. Not including the soldering part, these are the tools I found helpful for disassembly/reassembly. I went with the Chris method, which will require a long screwdriver. I was able to remove all the black screws except for the impossible screw (you'll know the one) with the haphazardly built extension piece on the ¼ drive screwdriver, but needed a single-piece 8 inch screwdriver for the impossible. Someone suggested buying a 24 in screwdriver at HF, which would also be a good idea. Removing the back of the oven is tedious so a drill driver with a quarter squeeze on the trigger makes this process faster. Jeweler's pliers came in handy for reinstalling the recessed screw holding the control panel and I always manage to cut myself when working with sheet metal so gloves. A telescoping magnet also helps when (not if) you drop a screw.
3. If I were to do it again, I would probably try the Phil method first, but if that isn't happening, I did not find the Chris method too onerous. Remove the impossible screw last and put it back first by presetting it in the hole before sliding the control panel back in. In regards to the picture, I found a bit of Hi Chew candy was helpful for holding the black screws until I could get them started during reassembly.
4. This picture shows the correct alignment of the rubber piece on the plastic cover.

My oven works until about 1 min to go on all cycles. At that time, the display clicks on and off until the cycle has completed. The element remains bright during the display flashing so it is either keeping power or getting intermittent power during the problematic time period. Unfortunately, the described remedy in this post didn't solve the problem.