Crockpot gving E1 error as its heating up

[netdef]

first post so here goes, i buy a lot of crap hoping i can fix and use or sell on.
Ive got a crock pot that when i turn it on its starts to heat up but then goes off giving E1 error.
I thought it might be the pressure switch but that such simple design and i checked it. so thought it might be a thermostat that might open/close when it shouldn't but that didn't stop it
so i can only think its something on the board, just after advice on the board of what it could be. cant see anything obvious.

[themadhippy]

Might help if you found out what E1 means

[netdef]

 E1. Internal circuits have disconnected

Thats all i can find about it.

[wasedadoc]

The board in the photo is only power supply and relays.  There must be another board.

[Gyro]

The board in the photo is only power supply and relays.  There must be another board.

I see no switcher circuitry for the SMPS transformer, so it will have SMD parts on the underside.


P.S. There will be another display / interface / controller board connected to that header (CN1) of course, but I guess if it is complaining about disconnected circuits , the problem is probably centered on the board shown. We do need to see the underside. A failed protective thermal fuse will also be a prime candidate (unless it is wired to cut power to the entire unit rather than just the heating element).

[netdef]

sorry late replay, my car has died so bigger problems. see attached the underside and the power control board. The only thing looking dodgy to me is the chunk of solder over the 4 pins of the chip/contoller/mosfet/timer???  i have no idea what is.

[wilfred]

I found the same website for error codes you evidently did. I found six error codes and you can glean something from the others as far as what it is not likely to be. Not overheating or pressure related. But it is working well enough to be able to display a code. So power is getting to the microcontroller.

I would start with looking to see if it heats up at all. there might be a thermal fuse that blew. Or the heating element is faulty or a relay or triac gas failed an the element cannot heat up.

I'd check for cracks in solder joints. particularly around connectors and heavier components that could vibrate or flex under mechanical shocks.

Does the appliance look like it has any damage externally that might indicate it has been dropped or abused in some way?

[netdef]

Looks brand new, it was a shop return so think error is straight from manufacturer. never been cooked in . only other think i can find is this (see Attached) thermistor??

[themadhippy]

only other think i can find is this (see Attached) thermistor??

Looks more like a thermal fuse.Top tip ,dont solder in a replacement.

[MrAl]

first post so here goes, i buy a lot of crap hoping i can fix and use or sell on.
Ive got a crock pot that when i turn it on its starts to heat up but then goes off giving E1 error.
I thought it might be the pressure switch but that such simple design and i checked it. so thought it might be a thermostat that might open/close when it shouldn't but that didn't stop it
so i can only think its something on the board, just after advice on the board of what it could be. cant see anything obvious.

What happens if you leave it that way.

Also, what happens if you pull the plug for three seconds and plug back in, and possibly turn it back on.

[wasedadoc]

That is a thermal fuse.  Should measure very close to zero Ohms.

The 8 pin chip with 4 pins joined with solder blob is the IC for the switch mode power supply for the electronics.  As display is working and showing a believable error code (ie not random segments) that power supply and the processor are almost certainly OK.

Examine the relay and its PCB tracking to determine which are the pins for its switch contacts.  (Not its coil). Temporarily short those contacts and see if the heating element begins to get warm when plugged in for a short time.

[WimWalther]

I'm sorry for saying this, but why on Earth would anyone want a crockpot with a digital microcontroller?

Four-position switches have served fine for.. 65 years? Hi, Lo, Warm, Off. I don't think that most even had a thermostat - beyond a hi-limit fire safety.

Btw, while I'm here, GET OFF MY LAWN!

[MrAl]

Hi,

I had asked about the behavior because it might be able to determine if something thermal is causing the problem or not.

If the unit is plugged in and it turns off, if we were to unplug it and plug it back in after 1 to maybe 5 seconds,  is it possible to turn it back on right away?  If not, it is probably something heating up that is causing the problem.

[BoredFish]

Dunno if you've noticed this or not, but over by C9 on the 2nd picture, there seems to be something bridging that gap over there that looks like it isn't supposed to be there. I'd look at it and maybe reflow it?

[wasedadoc]

Dunno if you've noticed this or not, but over by C9 on the 2nd picture, there seems to be something bridging that gap over there that looks like it isn't supposed to be there. I'd look at it and maybe reflow it?

That something is across the two pins of the socket on the other side lablelled NTC.  Perhaps that is where the temperature sensor plugs in,

[WimWalther]

NTC = Negative Temperature Coefficient (thermistor).

NTC thermistor are typically used as CILs (Current Inrush Limiters) in devices that expect high startup current surges. Unlike most conductors which increase in resistance as they heat up, parts with a negative tempo start off at some high-ish resistance and then decrease in resistance as they heat up.

[wasedadoc]

NTC = Negative Temperature Coefficient (thermistor).

NTC thermistor are typically used as CILs (Current Inrush Limiters) in devices that expect high startup current surges. Unlike most conductors which increase in resistance as they heat up, parts with a negative tempo start off at some high-ish resistance and then decrease in resistance as they heat up.

If it were a CIL there would be no need to go to the trouble and expense of having it off the board with plug and socket. It would just be mounted on the board. More likely it is a temperature sensor for the cooking pot, especially if the digital display can show temperature.

[BoredFish]

I mean still something that shouldn't probably be shorted together. It's weird that there's so much isolation between the pins. They didn't want no interference.

[ejeffrey]

Dunno if you've noticed this or not, but over by C9 on the 2nd picture, there seems to be something bridging that gap over there that looks like it isn't supposed to be there. I'd look at it and maybe reflow it?

That something is across the two pins of the socket on the other side lablelled NTC.  Perhaps that is where the temperature sensor plugs in,

Yes, negative temperature coefficient thermistors are commonly used as cheap temperature sensors. They have a narrow operating range and aren't as stable as a PTC but they have a very steep resistance vs temperature curve which allows very simple circuits to read them. A typical one might have a 10 kohm resistance at room temperature and drops dramatically (5x) at 60 C.