My Roadster has been sitting indoors for 10 days at Dietsch Werks waiting for a new bumper to be shipped from Tesla. OVMS temps reports my motor to be 61C. The pack is fully charged in standard mode and the car is plugged in but it barely needs to charge for 60 seconds to replenish.
The motor is stone cold. 61C can't be right. The batter reports 22C and the PEM reports 34C and ambient is 18C.
Is it a case of bad data coming over the CAN bus?
Most likely the temperatures are stale, as the car has gone to sleep. To reduce vampire load, the Tesla Roadster turns off the temperature monitoring subsystems when the car goes to sleep. On the Apps you see this as the temperature appears gray (for stale, sleeping) or bright white (for live, awake).
If this is the case, the SMS reply you got back to the TEMPS command should have the word "(stale)" shown. Like:
Code:
Temperatures:
Ambient: xxC
PEM: xxC
Motor: xxC
Battery: xxC
(stale)
- - - Updated - - -
Thanks! I didn't know about that new command.
It works, but this looks troubling...
Temperatures:
Ambient: 4C
PEM: 18C
Motor: 0C
Battery: 252C
Should I be looking for smoke and flames from my trunk?
Curt,
That is bizarre. It looks like a signed vs unsigned problem, but I've never seen a negative battery temperature.
Can you send me a PM (or eMail if you have mine) with the date/time you saw this, and your vehicle ID? I want to have a look at the logs.
P.S. Actually 252C is not too bad. We originally stored battery temperature in a signed char (-128 ... +127 celcius), but had to change to signed integer (-32768 ... +32767 celcius) when we added support for the Think City vehicle. One version of that vehicle uses a Molten Salt battery that operates at 245 celcius (http://en.wikipedia.org/wiki/Molten_salt_battery). You actually have to heat it up, to melt the core, before you can drive it.
P.P.S. Molten Salt Batteries should not be confused with Molten Salt Reactors (http://en.wikipedia.org/wiki/Molten_salt_reactor). Those operate at up to 1000 celcius, so could conceivably be monitored by OVMS (although you probably wouldn't want one in the back of your car, for reasons other than temperature) ;-)