WetEV wrote: lorenfb wrote:
WetEV wrote:Two fuse pulls in the next 7 months. Sure, not enough data. But if there is a relationship between activity and lockups, it is weak.
Try not using any TCU functions. I've had NO problems or fuse pulls in over 9 months. The TCU just doesn't become active without any
presetting of modes or use. So what can be said with certainty is that there's a lower probability of the TCU 'hanging' if it's not used.
WetEV wrote:If the rate of TCU fails is purely random with time,
That's your assumption. It's very rare that automotive electronics fail on a random basis, i.e. the failure is correlated to some
external occurrence (water damage, vibration, over-voltage, design error, etc.).
WetEV wrote:As I said, not enough data. Many theories, and I see no convincing evidence. I am not saying you are wrong, just that I'm not convinced.
1. Most who have problems use the Nissan app Connect or reminders, i.e. the TCU waits for an end of transmission
before powering down.
2. It's unlikely that the TCU fully powers-up without a remote request (or a reminder mode to transmit) causing other
ECUs on its CAN to also power-up resulting in a high current drain on the 12V battery. One wouldn't expect the TCU
system design to be that grossly marginal, i.e. a remote request would have to occur in its startup routine as the
TCU constantly monitors its radio in the low power mode.
WetEV wrote:I've also noticed what looked a TCU hang that cleared without a fuse pull. If you never use the remote features, would you notice this? Maybe you didn't have 0 hangs after all.
Right, some remote requests, i.e. various TCU remote requests require different outcomes (different microcode routines), may not
result in TCU hangs.
WetEV wrote:Also, the car uses the TCU to update charging stations. How did you stop that?
Yes, I've used the charging station update without any problems, but again that function has a unique routine when completed
immediately powers down the TCU. Whereas other routines may enter a 'standby' mode waiting for a remote input (from Connect)
to power down.
It's become obvious this doesn't have a simple solution, e.g. OTA update or a dealer re-flash, and may not even be fully understood by Nissan.
It's a problem that the TCU vendor needs to analyze and fully understand to determine a fix. And there may not be fix without replacing
this 3G TCU, which Nissan most likely doesn't care to do at this time.
You're correct that comprehensive data is lacking to draw any definitive conclusions, but some of us have to make some assumptions to
avoid 12V battery problems until the issue is resolved.
Leaf SL MY 9/13: 64K miles, 49 Ahrs, 5.1 miles/kWh (average), L2 charges to 100% > 1000, max battery temp < 95F, min discharge point > 20 Ahrs