MY MR Coffee ECMP50 has two blinking lights
After 8-10 months or so, my Mr Coffee ECMP50 died too. Both lights were blinking. The power light and the ready light were both blinking, not the buttons. Thankfully, this was an easy fix for my machine. The machine heats water with a heating block that is controlled with a thermisistor. For safety, the power to the heating coil goes through a Sefuse thermofuse on either lead. Thus, if the machine malfunctions and the heating block heats continuously, the fuses will cut the power when the temperature goes too high. In my case, the thermisistor was fine, and replacing the fuses solved the problem. I think the microcontroller senses a failure to increase temperature and blinks to show an error condition.
Here's how I repaired mine, keep in mind there is life and property threatening risks in opening your machine, and that the fault is caused by a safety fuse, which should never be bypassed or altered.
For dissassembly, you'll need to start out by taking the bottom panel off. This has two saftey screws. You can easily get a safety screw bit set at Harbor Freight or maybe NAPA. Some of the screws are also under the rubber feet. Pulling it off, you'll need to cut a plumbers tie and disconnect the drain tube. Next, you'll need to remove the top cover. There are screws around the outer underside where the espresso head is, and there are three screws way down inside. You'll need a really long small philips screwdriver for those. The side knob does pull straight off and isn't connected to anything underneath; it may require some jiggering with to get it off. If you need to get the button panel off to get the top off, there are two screws under the label. Just poke right through. It's a plastic panel and not connected to the lights. The metal is separate and doesn't need to come off.
Once you get the top off, the heating block is located in the center of the rear, hanging from a metal plate held in by four screws. All of the wire connectors have a rubber cover and a locking mechanism that you'll have to squeeze a button to remove the wires. You'll also need to disconnect one of the plastic hoses from the bottom. It is held in by a split pin inside a small plastic block.
On the side of the heating block are two metal plates securing the wires. These are clamping the safety fuses to the block. I just removed the plates, slid back the insulation, chopped out the old fuses, and put in new ones. Soldering them in will blow them, so wire crimps are used. The fuses are carried by Radio Shack in the drawer with regular overcurrent fuses where they keep electrical components. Keep in mind that different fuses for different temperatures are available. Mine was 190 C, 10A. Never use a higher rated fuse, as this is a safety device!
You might test your machine before reassembling it in order to check that the thermisistor isn't gone too. You can safely test it with a ohmmeter. It should read around 110K +- 10K. If you hit it with some ice, it should increase in resistance. Heat will make it decrease in resistance.
When reassembling, ensure that all the hoses get new plumber's ties to ensure no leaking, and don't forget that drain hose! Remember again, tampering with this may induce leaking next to line voltage electronics making a lethal hazard, or disable safety devices which may start fires!
I would suggest never leaving the machine on while not in use, as it puts wear on the heat block and fuses.
on Jun 16, 2012