BillAinCT
Well-known member
Deleted
Nissan Leaf 2018 ZE1 service ev system no power in red
- Thread starter oddmar
- Start date
Help Support My Nissan Leaf Forum:
My latest theoretical fix is to DISCHARGE the 12V (disconnected) then reconnect and wait (a day) until the car properly finishes the recharging. The voltage drops from 13+ down to 12.4.
The logic behind this:
Car start recharging the 12V after 5 days (in this case)
Before it is finished this procedure the car gives the error (HV leak) No Power when trying to start.
The car normally switches the HV off as soon as the current from DC-DC to 12V drops. This current drops because the charging is done. When you replace the 12V with a perfectly charged new one, the current can not drop as there is no current. By ''restoring'' the Friday afternoon situation with a discharged 12V; the car is being given the opportunity to properly finish the procedure of "recharging the 12V while being OFF". This hopefully includes switching off the HV (to be seen as the drop in voltage from 13+ to 12.4).
The logic behind this:
Car start recharging the 12V after 5 days (in this case)
Before it is finished this procedure the car gives the error (HV leak) No Power when trying to start.
The car normally switches the HV off as soon as the current from DC-DC to 12V drops. This current drops because the charging is done. When you replace the 12V with a perfectly charged new one, the current can not drop as there is no current. By ''restoring'' the Friday afternoon situation with a discharged 12V; the car is being given the opportunity to properly finish the procedure of "recharging the 12V while being OFF". This hopefully includes switching off the HV (to be seen as the drop in voltage from 13+ to 12.4).
It appears from your photos that the traction battery is fully (or almost fully) charged. The car will not go into READY mode unless you can get the DTC's related to CAN Bus communication and EV system errors cleared. It appears that the control modules are active because there is over 600 mA draw when the 12V battery is connected. The DC-DC converter is not charging the 12V battery because the main contactor is not closing.
I have always been able to get the control modules to reset by following the process of clearing DTC's, disconnecting/reconnecting 12V battery, clearing DTC's, and repeating that process 2 or 3 times as noted in previous posts. Since that has not worked for you, I suggest that you disconnect the 12V battery and connect a 12V incandescent light bulb between the positive and negative cables. That will act as a load and discharge any residual energy stored in capacitors in power supplies of the various modules. Leave the bulb connected to the cables for at least 24 hours to make sure all of the control modules are completely dead. Then connect the charged 12V battery and attempt to clear DTC's several times. Make sure you select each control module and clear its DTC's. Step through all of the control modules in this process.
The 12V battery charging algorithm while parked is different for my 2019 than the earlier cars. My 2019 turns on the DC-DC converter for 5 minutes 24 hours after the car is turned off. It turns on for 5 minutes 24 hours after that 5-minute charge stops. This process repeats every day until the car is turned on. I suspect your 2018 functions the same and something happened during those 5-minute charging sessions while the car was parked.
I have always been able to get the control modules to reset by following the process of clearing DTC's, disconnecting/reconnecting 12V battery, clearing DTC's, and repeating that process 2 or 3 times as noted in previous posts. Since that has not worked for you, I suggest that you disconnect the 12V battery and connect a 12V incandescent light bulb between the positive and negative cables. That will act as a load and discharge any residual energy stored in capacitors in power supplies of the various modules. Leave the bulb connected to the cables for at least 24 hours to make sure all of the control modules are completely dead. Then connect the charged 12V battery and attempt to clear DTC's several times. Make sure you select each control module and clear its DTC's. Step through all of the control modules in this process.
The 12V battery charging algorithm while parked is different for my 2019 than the earlier cars. My 2019 turns on the DC-DC converter for 5 minutes 24 hours after the car is turned off. It turns on for 5 minutes 24 hours after that 5-minute charge stops. This process repeats every day until the car is turned on. I suspect your 2018 functions the same and something happened during those 5-minute charging sessions while the car was parked.
Cause and effect
The fact that the HV is live (not real READY, but live) causes the DTC (HV leak) and bricks the car
The HV leak causes the DTC', which will not appear when there is no leak (HV switched off().
It does not seem logical to keep shooting the messages as they help us by telling what the cause of the problem is (HV leak), which has to be addressed..
The fact that the HV is live (not real READY, but live) causes the DTC (HV leak) and bricks the car
The HV leak causes the DTC', which will not appear when there is no leak (HV switched off().
It does not seem logical to keep shooting the messages as they help us by telling what the cause of the problem is (HV leak), which has to be addressed..
As suggested by GerryAZ and ReptonAU, i have disconnected the 12 volt battery with a resistive load accross the + and - leads.
Let it sit like that for 24 hours. Reconnected the terminals to the battery and retried clearing error codes.
Still the same errors appear.
Here is a report from the tester.
http://yourls-prodeu.autel.com/1?param=Nr2aAv
The car is going to the service garage tomorrow, hopefully it wont be to expensive.
Thank you all for your excellent efforts to help me.
Let it sit like that for 24 hours. Reconnected the terminals to the battery and retried clearing error codes.
Still the same errors appear.
Here is a report from the tester.
http://yourls-prodeu.autel.com/1?param=Nr2aAv
The car is going to the service garage tomorrow, hopefully it wont be to expensive.
Thank you all for your excellent efforts to help me.
Those DTC's are all related to CAN Bus communication errors. I hope the shop finds and corrects the problem without blindly replacing every control module at your expense.
Stanton
Well-known member
I hope the OP does eventually report back with the (hopefully good) result...because failed CAN Bus controllers sure don't follow the failure mode: a battery pack run down to nothing over the course of a week. I would think a good 12v battery (and re-boot) would fix comm errors, but not power pack/system problems.GerryAZ said:
I did not suggest that at all. I suggested to discharge the 12V and afterwards let the car finish its (interrupted) procedure by letting it recharge the 12V.
P.S. You can not discharge the 12V in the car as it is currently being charged by the DC-DC (13+). You could put a flat battery in the car or drain the current one, but it needs to be disconnected first. (down to 11.5 volt should do the job)
P.S. You can not discharge the 12V in the car as it is currently being charged by the DC-DC (13+). You could put a flat battery in the car or drain the current one, but it needs to be disconnected first. (down to 11.5 volt should do the job)
The LEAF Spy screenshots posted by OP show that the traction battery is nearly full charge so either it was somehow charged or it was never dead (or the charge level displayed is not correct). I still believe all of the problems are related to CAN Bus communication issues.Stanton said:
BillAinCT
Well-known member
One technical reason this could work is there are several microprocessors with CAN communications that have nonvolatile storage and if this state is stored there this could be one way to correct it. The other would be to reflash or replace that module with that setting. If the 12V is dying they wouldn't use ram for that I guess.
Stanton
Well-known member
Thanks for the update; keep them coming!
I feel your pain as it seems so hopeless. Can I suggest you take a drained healthy 12V (<12volt) to the garage and replace the brand new 12V with the drained one. Go back the next day and drive home in the Leaf (hopefully).
I try to demonstrate my logic;
Car is OFF - running on 12V - HV bus dead
After 5 days the 12V got below the voltage threshold and the Recharge procedure starts
Car is OFF - HV bus becomes live to supply DC-DC to charge the 12V (at 14 volts)
POSSIBLE INTERRUPTION
Car is OFF - Current towards 12V drop triggers to stop charging - HV bus becomes dead - control back to 12V
To start the car it has to be OFF and the HV bus must be dead (else it would be interpreted as a leak)
Say at the INTERRUPTION if you would try to start the car, I believe you get the Service System error. This because at the start up procedure it expects the HV to be dead and as it is not; the car is interpreting the Recharge process as an HV Leak.
The real problem now is that you have put in a brand new fully charged 12V and the car is still in Recharge mode. It gets out of Recharge mode by the drop in current from DC-DC towards the 12V. This current can no longer drop as there is no current to be dropped (the 12V is fully charged). We have missed the 'event' that would have triggered the killing (making dead?) of the HV bus. So my idea is that you can get back to the status at the interruption and let the car fix itself (finish what it started).
P.S. I would not trust my Nissan Certified guy to do this job with gusto. So hopefully you get access to your own car if you indeed will try this.
I try to demonstrate my logic;
Car is OFF - running on 12V - HV bus dead
After 5 days the 12V got below the voltage threshold and the Recharge procedure starts
Car is OFF - HV bus becomes live to supply DC-DC to charge the 12V (at 14 volts)
POSSIBLE INTERRUPTION
Car is OFF - Current towards 12V drop triggers to stop charging - HV bus becomes dead - control back to 12V
To start the car it has to be OFF and the HV bus must be dead (else it would be interpreted as a leak)
Say at the INTERRUPTION if you would try to start the car, I believe you get the Service System error. This because at the start up procedure it expects the HV to be dead and as it is not; the car is interpreting the Recharge process as an HV Leak.
The real problem now is that you have put in a brand new fully charged 12V and the car is still in Recharge mode. It gets out of Recharge mode by the drop in current from DC-DC towards the 12V. This current can no longer drop as there is no current to be dropped (the 12V is fully charged). We have missed the 'event' that would have triggered the killing (making dead?) of the HV bus. So my idea is that you can get back to the status at the interruption and let the car fix itself (finish what it started).
P.S. I would not trust my Nissan Certified guy to do this job with gusto. So hopefully you get access to your own car if you indeed will try this.
I believe it is even easier, so just in case you have not yet tried the empty battery method.
Start electronics (2xstart no break) followed by switching ON and OFF headlamps and heater.
Please let me know how it goes.
Or let me know that I should mind my own business and stop being so incredibly annoying.
Start electronics (2xstart no break) followed by switching ON and OFF headlamps and heater.
Please let me know how it goes.
Or let me know that I should mind my own business and stop being so incredibly annoying.
