I have been running RUT950 at site for a year, using two SIM cards with SIM switch functionality enabled.
I started experiencing issues with SIM1 few week ago as event log shows the SIM card is not inserted, forcing the system to switch to SIM2. Modem would then switch back to SIM1 after a timeout which I had set.
After switch back, SIM1 then still shows as not inserted (“SIM state changed to not inserted (internal modem)”) and modem will re-switch to SIM2 again.
I could previously temporarily solve the problem by going to site, reinserting the SIM and rebooting the modem but issue crops up again after modem running for a couple of weeks.
I had recently updated FW to RUT9_R_00.07.06.13 which did not resolve the issue. Any solution for this?
The “SIM card not inserted” error is not commonly associated with firmware issues but may result from mechanical problems. Vibrations or other mechanical issues can cause the SIM card to lose contact with the router.
Here are a few things to consider:
Loose Contacts: Adding a layer of tape behind the SIM card can increase the contact pressure, ensuring a better connection.
SIM Contact Oxidation: In areas with lower temperatures, high humidity (80-95%), and salty air (such as near the sea), SIM contacts can develop an intermetallic oxide layer, especially if they are made of aluminum. This oxidation prevents proper contact. In this case, try cleaning the contacts with an anti-corrosion lubricant, isopropyl alcohol, or dielectric grease.