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Does anyone know which component on the BCM50 main board is the temperature sensor? Thanks.
Brian Cox
Georgia Telephone
Brian Cox
Georgia Telephone
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BCM50 Temperature Sensor 3
- Thread starter exsmogger
- Start date
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1
- Thread starter
- #2
I figured it out. It's a tiny SOT-23 package transistor (Q47) that's labeled 1P. When I use my rework station to blow hot air on this transistor for a couple of seconds the fan kicks on. It's located underneath the hard drive.
Brian Cox
Georgia Telephone
Brian Cox
Georgia Telephone
curlycord
Programmer
Good find....2 inches from the fan connector.
Flat, really small and black with 3 legs.
I held my finger to warm it up then pressed it over the chip for almost a minute then the fan kicked in.
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Flat, really small and black with 3 legs.
I held my finger to warm it up then pressed it over the chip for almost a minute then the fan kicked in.
________________________________________
=----(((((((((()----=
Toronto, Canada
Add me to LinkedIN
- Thread starter
- #4
I've got a BCM50 R6 that's misbehaving and throwing alarm 11407 (Platform status monitor - Chassis fan 1 speed is reading 0 for over one minute). I tried swapping in the transistor from an unrepairable unit, but it still acts the same. Must be something else in the circuit causing this problem. I'll update if I can find the troublemaker.
Brian Cox
Georgia Telephone
Brian Cox
Georgia Telephone
- Thread starter
- #6
I tried that and did get the 11408 alarm. The fans are both running, so I'm pretty sure it's a hardware glitch. System is patched to latest.
Brian Cox
Georgia Telephone
Brian Cox
Georgia Telephone
- Thread starter
- #9
The fan runs like normal on power up, then shuts off as it boots into Linux. After a few minutes and before booting is complete the fan turns on full speed and then gradually slows down. After bootup is complete the fan gradually speeds up again. There is a fan test when looking at bootup through the serial connection. The test runs normally and shows no problems.
I watched the boot sequence through the serial port and all is normal until the system starts the CoreTel service. That is when the fan kicks back on at high speed and throws the 11407 alarm. The fan goes back to normal within 15 seconds, before the CoreTel service has completed starting. So possibly there's an issue with the CoreTel software, but the system was also doing the same thing before I upgraded it to R6. This leads me to think that it is a hardware problem.
Brian Cox
Georgia Telephone
I watched the boot sequence through the serial port and all is normal until the system starts the CoreTel service. That is when the fan kicks back on at high speed and throws the 11407 alarm. The fan goes back to normal within 15 seconds, before the CoreTel service has completed starting. So possibly there's an issue with the CoreTel software, but the system was also doing the same thing before I upgraded it to R6. This leads me to think that it is a hardware problem.
Brian Cox
Georgia Telephone
- Thread starter
- #11
I had already swapped in a known working hard drive. It does the same thing. The system works fine, but the fan problem is annoying.
Brian Cox
Georgia Telephone
Brian Cox
Georgia Telephone
- Thread starter
- #13
I don't, but I do have a scope. I'll compare the readings with a known working unit when I have a chance.
Brian Cox
Georgia Telephone
Brian Cox
Georgia Telephone
koulioumbis
IS-IT--Management
something i found is when installing a BCM50 system vertical on a wall the fan does much more noise that installing the same BCM50 on a surface like a table. Strange but it happens. I tried 2 different systems and both they behave the same.
Nikos
Nikos
- Thread starter
- #15
The fan sits loosely in the slot. You might try putting a shim next to the fan to tighten it.
Brian Cox
Georgia Telephone
Brian Cox
Georgia Telephone
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The alarm "Chassis fan 1 speed is reading 0 ..." has nothing to do with the temperature sensor. Therefore, changing the sensor logically made no difference.
BCM50 systems were shipped with one or two fans. The PSM (Platform Status Monitor) component monitors the system temperature and adjusts the speed of the fan(s) as needed. PSM also keeps track of fans that were installed and "complains" if a fan is disconnected / removed.
If you had at some point a fan connected to the position 1 (i.e., fan 1 was detected by PSM at some point) and later removed the fan or moved it to the other position, PSM would keep generating the alarm you mentioned because it no longer detects the fan 1.
If you have a fan installed in the position 1 and it seems to be working, the culprit would likely be the sensor wire of the fan or the fan itself. If I remember correctly, the three wires to each BCM50 fan are ground (black), +12V (red) and RPM sensor (yellow), The yellow is used to track the rotation count - but the counter read by the PSM is zero, so PSM generates the alarm.
The PSM data about installed fans can be reset. If you currently have two fans, you could remove the fan in position 1, reset the installed fan data and run your BCM50 with just one fan. You should never see an alarm about the fan in position 1 after the reset, because from PSM perspective it was never installed.
BCM50 systems were shipped with one or two fans. The PSM (Platform Status Monitor) component monitors the system temperature and adjusts the speed of the fan(s) as needed. PSM also keeps track of fans that were installed and "complains" if a fan is disconnected / removed.
If you had at some point a fan connected to the position 1 (i.e., fan 1 was detected by PSM at some point) and later removed the fan or moved it to the other position, PSM would keep generating the alarm you mentioned because it no longer detects the fan 1.
If you have a fan installed in the position 1 and it seems to be working, the culprit would likely be the sensor wire of the fan or the fan itself. If I remember correctly, the three wires to each BCM50 fan are ground (black), +12V (red) and RPM sensor (yellow), The yellow is used to track the rotation count - but the counter read by the PSM is zero, so PSM generates the alarm.
The PSM data about installed fans can be reset. If you currently have two fans, you could remove the fan in position 1, reset the installed fan data and run your BCM50 with just one fan. You should never see an alarm about the fan in position 1 after the reset, because from PSM perspective it was never installed.
- Thread starter
- #19
ucxguy,
Thanks for the info. I ran the pdrcmd command you posted. In poking around I found I could run a fan test by issuing the command /nn/bin/psmtest -F and got the following results:
Fan 1:Failed full speed test. Fan speed is 0. It should be between 7600 and 65536.
Fan 2:Fan2 speed test succeeded
Since I heard the fan kick on full speed I am assuming the default fan (upper left corner) is #2, and the upper right corner fan is #1.
Another good command is /nn/bin/psmtest -h which tests temp, power and fans with the following results:
Remote Temp = 44.00
Local Temp = 41.00
Fan1 = 0
Fan2 = 3049
V2.5 = 3.29
Vccp = 1.41
Vcc = 3.30
V5 = 5.10
V12 = 12.06
The complete option list for psmtest is as follows:
Usage: psmtest options
-a - Display full system information
-s - Display system load status
-c - Display CPU information
-d - Display disk status
-i - Display interfaces activities
-u - Display USB status
-p - Display PCI status
-h - Display H/W status Temp, Power and Fan
-r - Display Router status
-f - Display FPGA status
-F - Display Fan status
Brian Cox
Georgia Telephone
Thanks for the info. I ran the pdrcmd command you posted. In poking around I found I could run a fan test by issuing the command /nn/bin/psmtest -F and got the following results:
Fan 1:Failed full speed test. Fan speed is 0. It should be between 7600 and 65536.
Fan 2:Fan2 speed test succeeded
Since I heard the fan kick on full speed I am assuming the default fan (upper left corner) is #2, and the upper right corner fan is #1.
Another good command is /nn/bin/psmtest -h which tests temp, power and fans with the following results:
Remote Temp = 44.00
Local Temp = 41.00
Fan1 = 0
Fan2 = 3049
V2.5 = 3.29
Vccp = 1.41
Vcc = 3.30
V5 = 5.10
V12 = 12.06
The complete option list for psmtest is as follows:
Usage: psmtest options
-a - Display full system information
-s - Display system load status
-c - Display CPU information
-d - Display disk status
-i - Display interfaces activities
-u - Display USB status
-p - Display PCI status
-h - Display H/W status Temp, Power and Fan
-r - Display Router status
-f - Display FPGA status
-F - Display Fan status
Brian Cox
Georgia Telephone
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