Sierra Wireless EM7590 – GNSS Enabled but No Fix / No Satellite Info

[mahmoud.elkayal]

Hi everyone,

I’m having trouble getting GNSS working on a Sierra Wireless EM7590 module.

The modem itself is working fine, but GPS/GNSS never gets a fix, and I always see “Not Available” or “FAILCODE = 4” when checking location status.

Here’s the situation and configuration so far:

AT

OK

ATI3

Manufacturer: Sierra Wireless

Model: EM7590

Revision: SWIX12C_02.02.03.00 2024/01/29 23:36:42

SVN: 05

IMEI: 357999720511841

FSN: DX5341003705H1

TS.25: 2024.1.1

+GCAP: +CGSM

OK

 

AT!GNSSCONFIG?

GPS:   1

GLONASS: 1

BDS:   1

GAL:   1

QZSS:  1

OK

 

AT!GPSAUTOSTART?

 function: 1

 fixtype: 1

 maxtime: 255 seconds

 nmaxdist: 100 meters

 fixrate: 1 seconds

OK

 

AT!GPSCONF?

0,1,"",4

OK

 

AT!GPSLOC?

Not Available

OK

 

AT!GPSNMEACONFIG?

Enabled: 1

Output Rate: 1

OK

 

AT!GPSNMEASENTENCE?

!GPSNMEASENTENCE: 5F

OK

 

AT!GPSSATINFO?

NO SAT INFO

OK

 

AT!GPSSTATUS?

1980 01 06 6 00:58:00 Last Fix Status = FAIL, FAILCODE = 4

1980 01 06 6 00:58:01 Fix Session Status = ACTIVE

No TTFF available

OK

 

AT!PCINFO?

State: Online

LPM voters - Temp:0, Volt:0, User:0, W_DISABLE:0, IMSWITCH:0, LWM2M:0

LPM persistence - None

OK

 

AT!IMAGE?

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID  BUILD_ID

FW  1  GOOD  1  0 0   ?_?     02.02.03.00_?

FW  2  EMPTY 0  0 0

FW  3  EMPTY 0  0 0

Max FW images: 3

Active FW image is at slot 1

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID  BUILD_ID

PRI FF  GOOD  0  0 0   002.000_002 02.02.03.00_GENERIC

PRI FF  GOOD  0  0 0   002.001_002 02.02.03.00_ATT

PRI FF  GOOD  0  0 0   002.000_002 02.02.03.00_TMO

PRI FF  GOOD  0  0 0   002.001_003 02.02.03.00_VERIZON

Max PRI images: 25

OK

 

AT!PRIID?

PRI Part Number: 000025C

Revision: 100.013_000

Customer: Generic

Carrier PRI: SWIX12C_02.02.03.00_GENERIC_002.000_002

OK

 

AT!GPSSUPLURL?

supl.google.com

OK

 

AT!GPSSUPLVER?

!GPSSUPLVER: 2

OK

 

AT+WANT?

Preferred: 1

Current: 1

OK

 

AT!CUSTOM?

!CUSTOM:

        "SIMLPA"       0x01

        "UIM2ENABLE"     0x01

        "GPSENABLE"     0x01

        "MBIMTYPE"      0x01

OK

Any help or suggestions would be greatly appreciated.

Thanks!

[jyijyi]

Problem is it cannot view any satellite
Do you connect all antennas?
Did you test in outdoor area?

[mahmoud.elkayal]

It is connected to antenna, and it is outdoor.

The antenna/setup is working with AMIT MDG100 and now I am trying to get it work with the EM7590 module

[jyijyi]

Is there any improvement for using latest firmware?

https://source.sierrawireless.com/resources/airprime/minicard/75xx/em7590/em7590-approved-fw-packages/

Other user can make the gnss work:

EM7590 / Sierra Wireless AirPrime Dev Kit –

The modem works on both interfaces (AT and QMI) and I can see the respective SIM cards I’ve tried (I can read the phonebook, see the IMSI etc). However the modem can’t seem to see the network nor GPS satellites. AT+CSQ reports no signal (99,99) I’ve checked the switch settings on the dev kit and they seem to be correct. I’ve got it powered with the barrel jack and am using the USB interface. I’ve plugged in all antennas, but think I’d expect some signal with only MAIN and GNSS (for the GPS…

[mahmoud.elkayal]

I have upgraded the firmware:

ATI3
Manufacturer: Sierra Wireless
Model: EM7590
Revision: SWIX12C_03.01.02.00 2025/04/25 14:37:44
SVN: 07
IMEI: 357999720511841
FSN: DX5341003705H1
TS.25: 2025.2.24
+GCAP: +CGSM

After few minutes it managed to pick up one satellite but with now location:

AT!GPSSATINFO?
Satellites in view: 1 (1980 01 06 6 00:08:24)
SV: 1 ELEV: 0.000 AZI: 0.000 SNR:25.000

AT!GPSLOC?
Not Available

AT!GPSSTATUS?
1980 01 06 6 00:05:31 Last Fix Status = FAIL, FAILCODE = 4
1980 01 06 6 00:05:31 Fix Session Status = ACTIVE

No TTFF available

This lasted for few minutes and then now it is back to no satellites:

AT!GPSSATINFO?
NO SAT INFO

[jyijyi]

how many satellite can AMIT MDG100 view?

Is that all three antennas have been connected to EM7590 module?

[mahmoud.elkayal]

AMIT MDG100 is able to get a fixed location using 10 satellites:

AT+QGPSLOC=1
+QGPSLOC: 170332.0,5204.660492,N,00101.525047,W,0.6,167.0,2,335.10,0.0,0.0,081225,10

I am just connecting the GPS antenna for now.

[jyijyi]

how many EM7590 modules have you tested?
I am wondering if this is a particular module problem.

[mahmoud.elkayal]

4 modules has been tested, could not get any working

[jyijyi]

so all modules can only view one satellite only?
could it be antenna problem?

[mahmoud.elkayal]

No, no satellites at all. just manged to get one satellite at that one instance I mentioned earlier other than that no satellites at all.

Well the same antenna has been used with AMIT MDG100, and I did manage to get a location. So this proves the antenna is working, does not it?

[jyijyi]

@mahmoud.elkayal

So this proves the antenna is working, does not it?

i am not quite sure, as other user does not see this problem:

EM7590 / Sierra Wireless AirPrime Dev Kit –

The modem works on both interfaces (AT and QMI) and I can see the respective SIM cards I’ve tried (I can read the phonebook, see the IMSI etc). However the modem can’t seem to see the network nor GPS satellites. AT+CSQ reports no signal (99,99) I’ve checked the switch settings on the dev kit and they seem to be correct. I’ve got it powered with the barrel jack and am using the USB interface. I’ve plugged in all antennas, but think I’d expect some signal with only MAIN and GNSS (for the GPS…

EM7590 not sending NMEA sentences

So we also do get NMEA messages occasionally. The issue is that it seems to just stop after a couple of seconds. Having looked into it further we are noticing a couple things From a cold boot, for the first 30 seconds or so, if we send !GPSSTATUS we would get Last Fix Status = None. At this point, if we are observing the NMEA port, we would see those no fix NMEA messages I mentioned in the first post After 30 seconds, if we send !GPSSTATUS again, we would now get Last Fix Status = Fail, FailC…

[mahmoud.elkayal]

I have tested also with other antenna that again I know it is working since it has been used with AMIT MDG100 and managed to get a location indoor and outdoor. But still no luck!

[jyijyi]

Have you started the nmea frame with at!gpsfix command?

[mahmoud.elkayal]

yes and it returns statements with no data

$GPRMC,,V,,,,,,,,,,N*53

$GPGSA,A,1,,,,,,,,,,,,,,,,*32

$GPGGA,,,,,,0,,,,,,,,*66

$GPVTG,,T,,M,,N,,K,N*2C

[jyijyi]

Probably you need to contact distributor for further investigation

[mahmoud.elkayal]

what you are suspecting the problem is?

[jyijyi]

i am not quite sure…
since you can view one satellite, it seems not to be software issue