[Ovmsdev] Cannot reset simcom stuck in PoweringOn state without removing module power

Craig Leres leres at xse.com
Sun Dec 1 07:51:22 HKT 2019

On 2019-11-24 19:26, Craig Leres wrote:
> I think ultimately would be interesting is a trace of the PWKEY pin on
> the simcom. I might try taking a wire to the board.

So. I tacked a wire onto the collector of Q2 on a v3.1 modem board 
(which is connected to the PWKEY pin of the simcom). While running it's 
1.8V, it goes to 0V for one second when you do either of:

     power simcom off
     power simcom on

See attached. The SIM5360 hardware design guide says, "PWRKEY should be 
pulled low at least 180ms to power on or 500ms to power off the module." 
So not likely a surprise to whoever wrote our code.

So far I haven't figured out how to wedge the simcom on purpose. But my 
v3.2 module simcom wedged when I was driving on Wednesday. While on the 
road I checked the iphone ovms app and it showed my location as being a 
couple of miles from my house even though I was more like 60 miles away.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: tek0029.png
Type: image/png
Size: 2013 bytes
Desc: not available
URL: <http://lists.openvehicles.com/pipermail/ovmsdev/attachments/20191130/0dbeb08e/attachment.png>

More information about the OvmsDev mailing list