Chosen Solution

Pressing the start button on my Breville BOV800XL toaster oven also triggers the convection button, and sometimes the Fahrenheit/Centigrade button, instead of turning on. I have to press the button many times, carefully, before the cycle actually begins. I suspect the button is flexing the PCB behind the control panel and display. How do I get the cover off, and how could I fix this?

Here’s where to get parts for it: http://www.ereplacementparts.com/brevill…

I had this same problem and fixed it today. Boy was it a pain in the butt! The issue is with the push button on the “Control PCB”. It appears that one of the legs in the switch no longer connects or shorts and it causes it to trigger the “Convection” button instead. The fix is to replace that switch or order a new circuit board. I ended up un-soldering the button used to switch from °F to °C and swapped that switch with the On/Off switch. Here’s how to get to that board (you’ll need hands and arms similar to that of an 8-year-old child): Start by flipping the toaster oven over and removing the feet. There are two screws on each foot and another two in the middleThe plastic part is slotted and will need to slide back in place when you put it back together. Keep this in mind for the re-assembly portion.After you have the feet off, remove the screws underneath that they were covering up. There is one screw in each corner on the bottom. These are the only screws you should need to remove from the bottom.Remove the back:Look at the back of the toaster oven and remove every screw that’s facing the back. There’s a lot of them and they’re all the same size.Next, slide the back of the toaster oven down by approximately 1/2" and remove it. It’s on there pretty tight.Remove the top case from the toaster:When looking from the back, the top and right side are slotted and held in place by tension.Above the control panel and on the left side (same side as the control panel) there are 5 black screws. 3 are on the side and two are along the top. They are not easy to get to. I suggest starting with the one in the bottom corner and work your way to the top, then get the two that are at the top. Again, this part sucks.Remove the control panel:Looking at the bottom of the toaster oven and about an inch in, there is a hole cut in the bottom and a single screw pointing “up” toward the top of the toaster oven. Remove it.Unplug the 9-wire red-and-white cable.Unplug the white nylon 2-wire cable.The Control PCB should now be free.Remove the PCB from the assembly:Remove the metal piece that’s over the white plastic. 2 screws.Remove the screws in the white plastic and take off the white plasticRemove the single screw holding the PCB down and take it off.Fix the PCB! Yay!The busted switch will be labeled on the “yellow” side as K101 and will be in between two LEDs. Remove the switch using a soldering iron.The °C/°F switch will be labeled on the “yellow” side as K103. Remove it with a soldering iron. Don’t mix the two up!The switches all go in the same way, the feet come out the left and right sides.Solder the switches back in place but swapping the K101 switch with the K103 switch.Put everything back together. Just do it all in reverse.When putting the white plastic piece back on the back of the PCB assembly, hook the long rubber strip on it first. Then put the bent metal piece on and into the slot on the rubber strip. Note that the three knobs on the front control panel are keyed and must fit into their respective PCB-mounted sensors in a particular orientation. If not, the PCB will jut out a little bit depth-wise and result in an incorrect fit during reassembly. (Thanks, Vladimir Kutz) Good luck and god speed! Pictures of the PCB with K101 already removed. Placement of the 5 black screws holding the front control panel to the top case. Picture of the bottom screw holding the front control panel to the top case.

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.

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.

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?