Nords
Well-known member
I have a technical question about LeafSpy Pro.
If I used LeafSpy Pro to delete the DTCs created by a fault in a cell of the main battery... which caused the red triangle... can those DTCs still be recovered by a Nissan service center’s mechanic?
The rest of the story:
We’re shopping for a new-to-us used Leaf. Today we drove to another town to test-drive one of the candidates. That test drive went well, and we’ll discuss it in another post.
As we were going up a steep highway to meet the owner for the test drive, we almost didn’t get there. On the steepest part of the uphill route, the weak battery on our 2017 Leaf shut us down. This is our Leaf that we've already filed a claim on for a replacement battery:
https://mynissanleaf.com/viewtopic.php?p=635048#p635048
Other than losing bars, we've never had any trouble until today. The car was apparently using full power to go 60 MPH uphill, and at least one cell of the battery couldn’t handle the discharge load. I’m guessing that one of the 192 cells dropped voltage faster than the rest of the pack, and that divergence must have been considered a fatal error by the battery management software.
I suspect it’s one of the cells that’s causing the warranty claim on the car. The battery’s continued losing capacity for the last 11 months and it’s now down to 7 out of 12 bars. However this was our first incident.
The dashboard lit up like a yellow & red Christmas tree, the car shifted to neutral, and an alert flashed that power had been shut off. (I caught a quick glimpse of the alert, but then I was busy dodging traffic to get to the shoulder.) All we could do was coast to the side of the highway. Considering the steep hill, it was a short coast.
Once we were stopped, I cycled through the display but couldn’t find the screen alert. The car had shifted to Neutral, and I could put it in Park, but it wouldn’t go to Drive or Reverse. The red triangle fault let me shut off the car and turn it back on, but even after several tries it would not let me shift from Neutral to Drive. I was sure we’d have to call for a tow truck. Game Over.
Then I remembered: we were going for a test drive, so I’d brought my OBD-II dongle with my iPad and its copy of LeafSpy Pro.
We plugged the OBD-II into our dashboard, brought up the app on the iPad, and read the diagnostic trouble codes. There were several DTCs (with short descriptions) for a battery failure caused by a cell voltage. I tried shutting off the car and restarting it, then re-reading the codes, but they didn’t clear.
Then I remembered that LeafSpy Pro can clear the DTCs.
I’ve never cleared DTCs before. It took me a couple of attempts, and I had to dive into at least two specialty menus with warnings like “DO NOT CLEAR these codes if you do not understand them.” After about three rounds of clearing DTCs and restarting the car, it agreed to go into Drive. We got up the rest of the hill and over to the other town.
I’m pretty sure that when the car first shut down and coasted, its weak cell was unloaded. Free from the heavy drain of driving uphill, it started to recover its voltage. Once the overall voltages got back into spec (and once we finally cleared the DTCs) we could drive the car again.
We did the test drive of the other car (that went fine), and returned home without incident.
Once we were home I re-ran the car’s DTCs, but none of them even rise to the level of a yellow triangle, let alone the red triangle.
This 2017 Leaf has already been validated for the battery warranty and we have a J code case number. Our local Nissan service center doesn’t need to see us anymore, and we don’t see a reason to share this incident with them.
We plan to sell this 2017 Leaf into Nissan’s battery-warranty buyback program.
https://mynissanleaf.com/viewtopic.php?t=34237
At some point perhaps it’ll be inspected. If a mechanic plugged in an OBD-II reader and read the codes, would they find any record of the DTCs that I deleted?
If I used LeafSpy Pro to delete the DTCs created by a fault in a cell of the main battery... which caused the red triangle... can those DTCs still be recovered by a Nissan service center’s mechanic?
The rest of the story:
We’re shopping for a new-to-us used Leaf. Today we drove to another town to test-drive one of the candidates. That test drive went well, and we’ll discuss it in another post.
As we were going up a steep highway to meet the owner for the test drive, we almost didn’t get there. On the steepest part of the uphill route, the weak battery on our 2017 Leaf shut us down. This is our Leaf that we've already filed a claim on for a replacement battery:
https://mynissanleaf.com/viewtopic.php?p=635048#p635048
Other than losing bars, we've never had any trouble until today. The car was apparently using full power to go 60 MPH uphill, and at least one cell of the battery couldn’t handle the discharge load. I’m guessing that one of the 192 cells dropped voltage faster than the rest of the pack, and that divergence must have been considered a fatal error by the battery management software.
I suspect it’s one of the cells that’s causing the warranty claim on the car. The battery’s continued losing capacity for the last 11 months and it’s now down to 7 out of 12 bars. However this was our first incident.
The dashboard lit up like a yellow & red Christmas tree, the car shifted to neutral, and an alert flashed that power had been shut off. (I caught a quick glimpse of the alert, but then I was busy dodging traffic to get to the shoulder.) All we could do was coast to the side of the highway. Considering the steep hill, it was a short coast.
Once we were stopped, I cycled through the display but couldn’t find the screen alert. The car had shifted to Neutral, and I could put it in Park, but it wouldn’t go to Drive or Reverse. The red triangle fault let me shut off the car and turn it back on, but even after several tries it would not let me shift from Neutral to Drive. I was sure we’d have to call for a tow truck. Game Over.
Then I remembered: we were going for a test drive, so I’d brought my OBD-II dongle with my iPad and its copy of LeafSpy Pro.
We plugged the OBD-II into our dashboard, brought up the app on the iPad, and read the diagnostic trouble codes. There were several DTCs (with short descriptions) for a battery failure caused by a cell voltage. I tried shutting off the car and restarting it, then re-reading the codes, but they didn’t clear.
Then I remembered that LeafSpy Pro can clear the DTCs.
I’ve never cleared DTCs before. It took me a couple of attempts, and I had to dive into at least two specialty menus with warnings like “DO NOT CLEAR these codes if you do not understand them.” After about three rounds of clearing DTCs and restarting the car, it agreed to go into Drive. We got up the rest of the hill and over to the other town.
I’m pretty sure that when the car first shut down and coasted, its weak cell was unloaded. Free from the heavy drain of driving uphill, it started to recover its voltage. Once the overall voltages got back into spec (and once we finally cleared the DTCs) we could drive the car again.
We did the test drive of the other car (that went fine), and returned home without incident.
Once we were home I re-ran the car’s DTCs, but none of them even rise to the level of a yellow triangle, let alone the red triangle.
This 2017 Leaf has already been validated for the battery warranty and we have a J code case number. Our local Nissan service center doesn’t need to see us anymore, and we don’t see a reason to share this incident with them.
We plan to sell this 2017 Leaf into Nissan’s battery-warranty buyback program.
https://mynissanleaf.com/viewtopic.php?t=34237
At some point perhaps it’ll be inspected. If a mechanic plugged in an OBD-II reader and read the codes, would they find any record of the DTCs that I deleted?