G-R-R-G; need a True config wipe

I’m suffering the dreaded Green-Red-Red-Green sequence. I have formatted and swapped SD cards and changed power supplies several times, yet I last at best a few days before I die again.

Some config is persisting - it joins my wifi even with a new blank SD - so I think the config issue is coming out of something non-volatile. I work fine on the bench; it only dies after taking measurements…

Is there any way to truly, utterly, blast the config to factory default (at least, see it go into AP mode)?

This unit ran flawlessly for months and now won’t last a week.

You have two separate issues here. Your WiFi configuration is not maintained in the config file. It is stored in the ESP8266. You can clear that by selecting

Tools->WiFi->Disconnect

The LED should turn red indicating not connected, and then power cycle and you will get RGG for three minutes indicating AP mode to connect and specify new WiFi credentials.

Alternatively, you can shut down the WiFi it is currently connecting to and power cycle. The LED will go RGG and you can connect to the AP to specify new WiFi credentials.

If you are getting GRRG indicating a damaged config file, and you are not editing the config, then the SDcard is probably defective.

The cards should be >=8GB and <=32GB SDHC. They should be formatted FAT32 with the SDcard Association formatter.

If that doesn’t resolve your problem, you might check the SDcard holder pins where they solder to the PCB. It’s possible that with frequent use, one or more has become loose. Touching each with a soldering iron until the solder flows will insure proper contact.

GRRG is not a common problem. Typically when a card fails, it does not manifest as a bad config file. Most often the datalog is damaged as it is thousands of times larger and accessed orders of magnitude more often than the config. If, as you say, the config appears fine when the card is mounted elsewhere, and then when inserted into the IoTaWatt you get GRRG, then please upload a copy of the file in a PM and I’ll take a look at it.