Jean Paul O Houston , TX July 14, 2015 Appliance: Model BOSCH 300 SERIES BUILT IN OVEN. MODEL NO. HBL3450 Main computer board on oven Our Bosch 300 series built in convection oven, which was 18 months old, failed to properly regulate temperature. It either got super hot, in one instance actually igniting a peach cobbler, or after a half hour the oven had only risen a few degrees. Called two local repair companies. One charged $65 for a service call plus $120 an hour. The other charged $90 for a service call plus $125 an hour. Went with the cheaper. Probably a mistake. The tech came out and asked if there had been any error codes. We said no. He pulled out the oven and observed the computer board but did not do any multi-meter or other testing. He just proclaimed the computer board was dead, that they go out all the time regardless of brand. He wanted to charge $500 for the part and $200 to install for a total of $700. We called for a price on the part at repair company number 2 and were told $191. We located the part at Appliance Parts Pro for about $185 with shipping. Didn't see our oven on any YouTube repair videos but saw enough others to figure we could do it. Actual repair took about 20 minutes and saved us $450. The repair was really easy. The hardest part was taking off and putting on the oven door. After that, just take your time and stay organized. Read More... 5 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 15-30 minutes Tools: Screwdrivers