Pit probe problem


 
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Ivo Oude Veldhuis

New member
I have a problem with my pit probe of my new soldered (2nd) HM board. If I plug it in, the display keeps saying -no pit probe-.
I have searched the forum and found the following part.

Bryan Mayland said:
I'd say troubleshoot the hardware first. Get a multimeter on the probe connector J2. Measure the voltage with nothing inserted into the pit jack between pin 1 (labeled GND) and pin 2. You should get 3.3V. Now insert the pit probe and the voltage should drop. You should get this same voltage at pin 28 of the ATmega chip. To determine the voltage you should see, remove the pit probe and measure the resistance (R). The voltage from the preceding step should be 3.3 * R / (R + 10000).

If that's working then check your probe configuration in the web interface. If that looks right, maybe use the menu on the HeaterMeter itself to "Reset configuration", power everything down, and back up again, then try configuring the probes again from the web interface.
Click to expand...

I measured the probe jack, when nothing is connected, it shows 3.3V, now when I plug in the probe, the voltage drops to 0V like it shorts out or something. Any idea where this problem may lay ?
The other jacks work properly.
 
If you're using ET732 probes & 10k resistors, you'll get ''no pit probe'' at room temperature. Warm them up to ~90*F & they will work. You can either A) deal with it or B) change the 4x 10k resistors to ~22k.

My ET73 probes work fine down to 32*F, my ET732 probes say --no pit probe-- until they heat up to 88-94*F
The HM 4.0 was designed with the ET73 Probes in mind.
 
Ivo Oude Veldhuis said:
I measured the probe jack, when nothing is connected, it shows 3.3V, now when I plug in the probe, the voltage drops to 0V like it shorts out or something. Any idea where this problem may lay ?
The other jacks work properly.
Click to expand...
I'm not sure what's going on there. Like you say something is pulling it to ground when the probe is inserted. There's nothing unique about the Pit probe jack though so the only thing I can say is compare it to the others. Like see if mechanically something is creating a connection between the front and back pins of the jack.
 
I had the same problem and wrapped a small wire from around the shield braid to the probe jack input and it seemed to fix the issue. This was after seeing a mod that soldered the braid to the post to fix a grounding issue on the et-732
 
I am using the ET-732 but modded them so they don't go in at max. The probes are working perfectly on jacks 2,3 and 4 and also on jacks 1,2,3 and 4 of my other HM board.
I am going to desolder it and switch it with another working jack to see it the jack itself is the problem.
 
I have had to do the same as AaronB. I took a short length of solder, wrapped it around the braid on the wire several times and then up around the base of the plug tip. It fixed the no probe issue, as well as it keeps the plug from going in too far. I do not know if they changed something on the Maverick 732 pit probes or what as an older one I have works fine without doing this, but the 2 newer pit probes I have, require the solder mod to make them work reliably
 
I bought the 2 pack "ET-71/ ET-73/ ET-77/ ET-901 FOOD Probe" from Maverick. Came with one food probe and one pit probe. I found that the pit probe's plug is slightly longer than the food probe due to differences in the plastic molded around the plug. I just have to back the pit probe out a little bit and it clicks into place.
 
Ok, problem lays in the jack itself. Switched 2 jacks and now pitprobe works and food 1 doesn't. The jack itself seems to have a problem that it's shorting out when something is connected.
 
I see that this thread is quite old; however, I recently completed my 4.2.4 HM build (with thermocouple for the PIT probe), and I had this same issue as described by Ivo Oude Velhuis with food probes 1 & 3 (probe 2 mostly worked as expected). I am using the ThermoWorks TX-1001X-OP probes. What I observed was that there was a "sweet spot" while inserting the probe where it would work but inserting the probe more or less into the jack on the HM would cause it to stop working. With my multimeter, I discovered that, in fact, the jack was "shorting" (specifically the gnd/shield pin to pin2/tip). Inspecting the jack hardware carefully, it appears that as the tip is inserted into the jack, the contact in the jack that is engaged by the tip flexes toward the front (ground shield) of the jack and slightly upwards making contact with the shield/gnd material at the front of the jack. I was able to take a small flat-blade screwdriver and ever so slightly flex/bend the contact back slightly so that it no longer shorts out to the front of the jack. I am not sure if I received faulty jacks with my order, or if I subjected them to too much heat when I soldered them causing the contact to warp slightly (ironically, my soldering skills were good enough to mount all of the SMD components for the thermocouple without issue on the first try!). In either case, I hope that this information might help someone else down the road.
 
Hi All - I'm in the middle of my first cook. I just put a chicken on and am using the ThermoWorks TX-1001X-OP probes for both PIT temp and in my chicken. I think all my settings are right, but the temperature for the chicken should be closer to 80 degrees right now. I tried in all the food jacks. Once in awhile it seemed to read the correct temperature but then would shoot high again. Any ideas?

Here is a link to my settings

https://www.dropbox.com/s/wdl5ksr68vka0bq/Capture.jpg?dl=0

Edit: I forgot to mention that if I unplug the pit prob, the temperature for the chicken seems to report correctly.

Also -my first cook has been interesting. This definitely takes some practice. I'm using a weber kettle and way overshot my target even with only 12 lit coals. I should have taped all the vents from the begining.
 
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It may just be a connection issue with the Jack - Some wiggling seems to fix the temp. Has anyone done any jack modifications or found different jacks for the THermoworks probes?

It also could easily be that my soldering sucks.
 
I found that I had very slight interference between the plastic of the plugs on the thermoworks probes and the 3d printed case on my first heatermeter build, easily remedied in my case by taking an exacto and carving away a bit of the edge of the plastic on the probe plug so that it could insert fully. Until I cleaned that interference up, my thermoworks probes would bounce all over the place, reading unreasonably high, then dropping to normal. Worth checking.
 
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