2 new HeaterMeter build not working at all


 

JeffLa

TVWBB Member
Hi,

I successfully build a HeaterMeter v4.3 a couple of years ago and decided to build two more for friends. I have completed the builds and sadly neither one works. I am using a Raspberry Pi 3B for all three. Since I had a good one, I tried testing the known good boards from my old one with the new boards. Literally nothing new works. The only thing that does work are the two new Raspberry pi 3b boards which I tested with my old setup. Both of them work fine with my older hardware.

I looked things over under a microscope and can't find anything. One thing I did note is that the version of the HeaterMeter baseboard has changed. A resistor and a Diode (D3) and the 1K Resistor have swapped positions and another Diode D2 polarity looks to have been reversed. The pictures in the assembly instructions are a mix of versions, which is confusing (the blue board at the beginning is an older rev). I assembled the new ones following the silkscreen on the board I have so it should be corect, unless there is a silkscreen mistake.

The new button boards are also not working. I tried connecting the new button boards(soldered to the LCD display board) to my known good baseboard and Raspberry pi, and I got nothing on the display for either one.

I tried turning the pot (R6- 10K ohm) to see if that did anything and nothing happened.

Anyone have suggestions?

Beat regards,

Jeff Lavin
 
I'd start with posting some good, high res pics of the front and back of the boards that aren't working.
 
Regarding the assembly images, I posted all new images to match the 4.3.4 layout a couple of days ago. GitHub tries to anonymize all client image requests by running them through a proxy/cache which can lead to some weirdness of a mix of old and new images showing up. I just tried to update that purple image again and now it shows up but it is smaller for some reason? That's just weird. In any instance, there are only three pieces different and they're very clearly marked on the board the pieces are going into.

If all your new parts aren't working then we've got a massive amount of troubleshooting to undertake. The easiest thing to do is to start with just one piece and get it working then move on to each other piece in turn instead of trying to examine 4 different boards at once. I'd suggest trying to get one new LCD/Button board working with your old/working base board first as it has the fewest number of variables compared to a base board.
 
As I mentioned, I recently built two new HeaterMeter 4.3 kits. I have an older one that works. None of the new boards I have build are functioning so far. I am testing them by swapping them into the working HeaterMeter.

I decided to start with the simple case - a button board + display. I compared the non-working ones from my recent builds to the old one that works and I cannot find any difference. The resistor values are all correct, the LEDs are all installed with correct polarity, the display board is soldered correctly, etc. I even re-heated all of the solder joints to eliminate a possible cold joint. I used an ohm meter to measure the resistance across each resistor (knowing they are in circuit, so values won't mach the resistor value), just looking for difference. They are the same.

When I test it by plugging the working controller board and Raspberry Pi 3B from my original working build into the display/button board combo I am testing, the display backlight comes on, but there is nothing displayed. If I press the up button, the yellow LED comes on, so seems like things are working except for the display. I tried turning the 10K potentiometer for the contrast but no joy. Results are identical for both.

Is this a legitimate way to test? Should the display function when plugged into an older build? Based on the fact that both new boards behave the same way with the older controller, I have a suspicion that there was a change made to the controller that has made the newer button board incompatible with the older controller board. Is this possible?

I have pictures, but am not sure how to post them here. It asks for a URL....

Best regards,

Jeff Lavin
 
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Unfortunately I didn't jump in and build the first iteration of the HMv4.3 so I do not have the evolution cataloged in my brain as well as previous versions, though I seem to vaguely have recollection of some change on the button board that might confirm your suspicion. Bryan would be the guy who can confirm or debunk that theory. I know he did change around the voltage setup on the buttons for v4.3 compared to v4.2, not sure if that evolved or if it came out of the shoot that way?

I assume when you connect your working HM board and rPi to this button board you can connect via web interface? If this is the case you should at least be able to confirm that the left button works (use web gui to set a target temp, when you hit the left button you should see Lid Mode toggle on/off)

You can go down a similar road trying to troubleshoot the non-working base boards. Connect the working rPi to the non-working base board. Does it boot and allow access to the web interface? Does it communicate with the HM board? You can verify this by seeing if the probes register, fan runs etc. If you can get a new base board build working you can then troubleshoot the button boards with it.
 
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The solderwork looks rough, there is at least one pin on the shift register IC that looks like solder didnt flow well, and there is flux all over everything.
I would start out by cleaning the board with some alcohol and a soft brush (maybe an old toothbrush if you have nothing else). let it dry thoroughly before powering it up. After cleaning inspect closely for solder joints that need touchup, particularly those on the IC and LCD header.
 
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I just built my first HMv4.3 last night and it went very well, took only about an hour and it worked first time I plugged it in. So far I have built only the base board and am using it headless.
If you want to troubleshoot your base boards this is a good time, I have a unit right here I can use as a reference to help you.....
 
I just built my first HMv4.3 last night and it went very well, took only about an hour and it worked first time I plugged it in. So far I have built only the base board and am using it headless.
If you want to troubleshoot your base boards this is a good time, I have a unit right here I can use as a reference to help you.....

Hi Ralph,

I will clean up the boards. I didn't cut the leads before soldering, but I am definitely not skilled at soldering. Frankly I am now of the belief that doth f the button/display boards are working fine, but just are incompatible with the older base controller board. I'd love the help debugging those. I found a pad missing solder yesterday and fixed it hoping that would be the problem, but no joy.
 
I found the base board build for the HMv4.3 to be very straight forward, why dont you pick one base board, take a closeup picture of both sides and post them and we'll start troubleshooting there.

Mate this board with your known working rPi (without the button board attached) and attempt to connect to it with the web interface (as you would do for your completely working HM). Can you connect? if so, plug in some probes, do they register? We can move forward from there.
 
I'd still stick with trying to get the new LCD/Button boards working with the old, working HeaterMeter base. The 4.3.3 and 4.3.4 versions are pin compatible on the headers so they should be interchangeable. There's not much circuitry in play so troubleshooting it should be straightforward compared to the number of things that cause a base board to not function.

With the LCD/Button board not connected to anything, put your multimeter in continuity mode and check that no LCD pins are linked to the pin next to it. Also check the shift register pins for the same thing. Then test each pin on the shift register to the pin with the same label on the LCD. They should be connected. Finally test from the shift register's LCK, SCK, MO pins to their pins on the 5 pin riser headers which also should be connected. That's the whole deal right there. If none of your pins are shorted, and all those that are labeled the same are connected, then it will work.

You can also test between pins 1 (GND) and 3 (CNT) on the LCD when it is powered and there should be about 1V when the contrast is adjusted correctly (all the way counter-clockwise, then back about 1/4 turn). Test it at the LCD side, not on the potentiometer to make sure it is getting to the LCD.
 
I'd still stick with trying to get the new LCD/Button boards working with the old, working HeaterMeter base. The 4.3.3 and 4.3.4 versions are pin compatible on the headers so they should be interchangeable. There's not much circuitry in play so troubleshooting it should be straightforward compared to the number of things that cause a base board to not function.

With the LCD/Button board not connected to anything, put your multimeter in continuity mode and check that no LCD pins are linked to the pin next to it. Also check the shift register pins for the same thing. Then test each pin on the shift register to the pin with the same label on the LCD. They should be connected. Finally test from the shift register's LCK, SCK, MO pins to their pins on the 5 pin riser headers which also should be connected. That's the whole deal right there. If none of your pins are shorted, and all those that are labeled the same are connected, then it will work.

You can also test between pins 1 (GND) and 3 (CNT) on the LCD when it is powered and there should be about 1V when the contrast is adjusted correctly (all the way counter-clockwise, then back about 1/4 turn). Test it at the LCD side, not on the potentiometer to make sure it is getting to the LCD.

Bryan,

I'll do that and report back. Can you confirm that the newer LCD/Button board should, indeed function with the older base board? Since both of my LCD/Button boards behave the same with my old working base board, I had assumed maybe they are maybe OK and just won't work with the older base board.

Jeff
 
Bryan,

I'll do that and report back. Can you confirm that the newer LCD/Button board should, indeed function with the older base board? Since both of my LCD/Button boards behave the same with my old working base board, I had assumed maybe they are maybe OK and just won't work with the older base board.

Jeff

Progress! One of the two button boards now works. I found a pad missing solder and that fixed it.

For the remaining board I did all you recommended and there is a problem with the voltage in the CNT pin on the display. It is 4.95 volts and not changing with the pot. I checked with the meter to see if there is a short to 5V and there isn't one. There is continuity to the pin on the potentiometer. I tried to find any other shorts to that pin on the board and counldn't find one. Any ideas?

Thanks,

Jeff
 
Ah fixed the 2nd LCD/Button board! It was a cold solder joint on pin 1 of the Potentiometer. Ok both LCD/Button boards are working. I found a broken pin on one of the BS170 transistors on one of the 2 bad base boards, so I'll need to get hold of a spare to fix that. I'll focus on getting the other base board working now.

Jeff
 
Big day - Found the problem on the base board and it is now working. All that remains is the 2nd baseboard which has a clear problem with the transistor witha broken lead.
 
You're knocking 'em down today, NICE! I hate to see people struggling to get their HM up and running, building it can be part of the fun, but most of the fun comes when you actually get the thing working and running your pit....
 
I sent a note to the HeaterMeter store begging for a replacement BS170 transistor so I can get the last baseboard up and running.

Now I just need to solve the problem mounting to a large BGE. I don't like the solutions that are out there because you have to use the heatermeter for normal grilling and I really only want it for smoking. I devised a very cool mounting box that made it easy to mount the micro-damper for smoking and remove it and use the original door for normal grilling, but sadly it warped due to the heat. If I figure out a robust solution, I'll share with the community. Thanks again to everyone for the assistance. It was very helpful and motivating.


Jeff Lavin
 

 

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