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Timothy Woo edited this page Aug 1, 2019 · 63 revisions

Here is a list of common issues. But before we begin, probably the biggest "issue" users have is trying to use the Hologram SIM card in Europe or other places where the SIM card may not support LTE CAT-M1 or NB-IoT networks (these are new technologies and Hologram hasn't partnered with everyone yet). If this is your case, please get an LTE CAT-M1 or NB-IoT SIM card from a local provider and it should work fine. Another issue is not using a 3.7V/1000mAH+ LiPo battery; it's absolutely required for this shield unless you wire it up externally and use a strong power supply and 3.3V logic. Again, you cannot rely solely on the Arduino's 5V rail!

General Questions

Q: What boards is this shield compatible with?

A: This shield is directly compatible with 5V Arduino boards that have the standard Arduino header configuration and software serial RX support on pin 10. This includes Arduino Uno, Mega, and Leonardo. However, feel free to manually wire up the board instead of using it as a "shield" (in the sense of the term) to make use of the additional hardware serial ports on many Arduino boards including Arduino Mega, Due, Zero, and many more. This will allow you to use a higher baud rate (115200) without changing the default baud of the SIM7000 module. Please refer to the pinout documentation

Q: Does this shield work with Raspberry Pi?

A: Certainly! You just have to wire it up externally and I've included full documentation of the shield's pinouts. Note that since the Raspberry Pi runs on 3.3V logic you will need to follow the instructions on how to configure the logic accordingly.

Q: I live in XXXX country. Which version should I choose?

A: There are three versions of the shield and it's important that you select the right one! For help on this please visit this Github wiki page. Note that this shield does not work on traditional LTE like CAT-1, 3, 5, 6, etc., so make sure you have CAT-M1 or NB-IoT in your area, or in the case of SIM7000C and SIM7000E, you can also use 2G or 2.5G fallback.

Q: Does the SIM7000 shield have audio support?

A: Unfortunately, no, this shield doesn't currently have audio support. However, check out the SIM7500 LTE CAT-1 shield which does support voice calling like a boss!

Q: Do I need a LiPo battery for my shield?

A: Yes, you will definitely need a 3.7V LiPo battery with capacity of at least 500mAH, preferably 1000mAH or more. This is needed because of the high current spikes during data transmission, connecting to a network, and especially with GSM fallback mode on the SIM7000C/E/G versions. Note: Make sure your battery's connector polarity is correct! There are some batteries that have reversed-polarity and this could cause damage to your shield and/or cause voltage conflicts and cause the module to shut off after booting up.

Troubleshooting

Q: The SIM7000 power LED isn't turning on when I power my Arduino. Is that normal?

A: This is perfectly normal! The power LED only turns on when the PWRKEY pin is pulsed LOW. This is taken care of in the example sketches I provide, so after you upload and run the code the shield should turn on shortly thereafter! If the LED on the shield doesn't turn on shortly after running the example sketch, see the next section. The shield must be on in order for the Arduino to find and communicate with it! You can also manually use a jumper wire and touch the PWRKEY pin to GND for a second or two, then release and the module should power on a few seconds later.

Q: The SIM7000's "PWR" LED is turning on, then it turns off by itself after a little while, even with a LiPo battery connected. What is causing it to shut down by itself?

A: If your shield is plugged into an Arduino board (or otherwise has 5V connected to the shield's "5V" pin) and your shield turns off shortly after powering up, check the polarity on your LiPo battery's JST connector. It has been reported several times that some batteries have reversed polarity, causing a voltage conflict and ultimately making the module shut down. There is a "+" sign marked on the left side of the JST connector on the shield; make sure your battery's red wire is on that side!

Q: The shield still isn't turning on, even after running the example sketch, or it turns on and won't establish communication with the module.

A: In some cases the physical connection between the stacking female headers and the Arduino headers may not be entirely secure. To debug the problem, try using a male-to-male jumper wire to temporarily connect the PWRKEY pin to GND for less than half a second or so (on v6 boards there is a pushbutton to do this easily) and see if the shield turns on. If it does, the physical connection of the headers might be an issue. To remedy this, tin the stacking female header contacts (mainly 5V/GND and pins 6, 10, and 11) with a small amount of solder to make the connection more secure and see if that helps.

Q: My shield isn't connecting to the network with a SIM card is inserted. How do I fix this?

A: The first thing you should do is make sure your SIM card is activated online. For a Hologram SIM card activate it on the Hologram dashboard. When activating you should also make sure you have the appropriate zone selected (zone 1 or 2). Next, in the Arduino code go to the line that says "fona.setGPRSNetworkSettings(F("hologram"));" and make sure you have the right APN settings entered. By default it's set to work with a Hologram SIM card. Also check to make sure the antenna is properly connected (remember, the antenna wires criss-cross). After that's done, run the "FONA_LTE_Test" sketch and enter the command "n" to see the network registration. If it says "Searching" wait a little bit and see if it connects. If it doesn't, enter the command "G" to enable GPRS and set the APN then see if it connects to the network. Some networks are simply not supported and I cannot guarantee that this shield will work with all SIM cards. I can confirm that the Hologram SIM card works on the Verizon network in the USA, and the AT&T Trio SIM card also works in the USA. Anything other than Verizon or AT&T is not guaranteed to work but please let me know if you did get another carrier working!

Q: My shield is constantly rebooting when I plug in a SIM card. What's causing this?

A: This is a common problem that occurs when you don't have a LiPo battery connected to the shield and is particularly important for SIM7000C, E, and G modules which support GSM fallback (which draws lots of current) but can also happen on SIM7000A units. If you get this issue and are sure you have CAT-M1 or NB-IoT connection in your area but want to try it without using a battery, try using "AT+CNMP=38" to set the module to only use LTE mode (and not GSM) and also "AT+COPS=0".

Another (albeit rare) possibility is that the SIM card is somewhat defective. This can cause the module to shut down after a certain period of time or other side effects such as only being able to receive text message but not being able to send them.

Q: I can't send any text messages from my Hologram SIM card within the US. Help!

A: If you are able to run the AT commands to send text messages but you never actually receive the text, please use the comand AT+COPS? to check if you are on Verizon's network. If you are, an easy fix would be to use AT+COPS=? to see the full list of available networks and connect to AT&T's LTE CAT-M network instead. Verizon apparently blocks the Hologram SIM card's country code (+88). For more information regarding this, please see this question on the Hologram forum

Q: I've done everything right and my module sees available networks with AT+COPS=? but I can't connect to them

A: If you simply cannot connect to the network and it always says not connected or searching, try running the command AT+CGDCONT=1,"IP","hologram" or AT+CGDCONT=1,"IPV4V6","hologram" then reboot the module (you can turn off with AT+CPOWD=1 then turn back on by pulsing the PWRKEY pin, pin 6) and see if it connects. It should then either automatically connect to the network but if it doesn't, use AT+COPS to connect to one of the networks listed out from AT+COPS=? These instructions are particularly useful for the SIM7000A-A version using the Hologram SIM card.

Q: I have a SIM7000E and sometimes the module will randomly crash and won't reset until I pulse the module's reset pin or reset power to it. What's causing this?

A: This particular problem was reported by a user of the SIM7000E running firmware version 1351B03SIM7000E and was fixed by updating the firmware version to 1351B05V01SIM7000E.

Getting Help

UPDATE (8/1/19): Please use the Botletics community forum for questions!

In order to get the most efficient support, if you can't solve your problem after reading the FAQ above or by reading this page of the wiki, please copy/paste and fill out the info below and include this in your request for support:

Problem Description: Not turning on, not connecting to network, not able to establish serial communication with the shield, power cycling, etc. (please be descriptive)

Country: USA, Norway, Australia, etc.

Hardware: Arduino Uno, Mega, Leonardo, Raspberry Pi, Espruino Pico, etc. (Please describe your setup)

Modem: SIM7000 shield and version (A, C, E, G)

SIM Card: Hologram SIM, AT&T Trio SIM, other? Is the SIM registered online? NOTE: You will most likely need a LTE CAT-M1 or NB-IoT SIM card from a local provider if you are outside the USA. Hologram does not have wide coverage for CAT-M1/NB-IoT outside the USA as these are relatively new technology.

3.7V LiPo Battery (>500mAH): Yes/No? NOTE: If your shield power cycles (turns on, then turns off later by itself, etc. then you will need a LiPo battery to fix the problem!)

Software: Arduino IDE, LTE_Demo example sketch, etc?

Send the responses for the following AT commands (the easiest way to do this is via USB)

  • ATI
  • AT+CGMR
  • AT+CREG?
  • AT+CFUN?
  • AT+CPIN?
  • AT+COPS?
  • AT+CSQ
  • AT+COPS=? (may take a while to run this command)