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Did someone notice that after the 2 modules software update the estiated time for fully charge is (in my case) 8hr and 15min, instead of 8.45 - 9hr that is used to, that is why I supose my car can only use 9kwh or 0.9kwh/1 bar of range.
 

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Is this also normal after BECM and HPCM2 reprogramm? I lose every energy bar at 0.8kwh used, so on 4.2kwh used my battery is already half instead of ~60% as it used to - see in the image below.
171035
 

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I still managed to get 80km with 9.3kwh used on a test at 80km/h on highway. Before HPCM2 update, I can get this range with 10.2kwh. The technician from Opel told me that the range is not that affected after update, instead, the method of calculation on kwh is changed....I don't know, maybe is right....
171065
 

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Looks to still be there.

View attachment 171011
Hi,

I finally figured it out. I needed to be in the USA to get it to work. A VPN connection later and the subscription was suddenly available.
Reprogrammed the module but the error comes back after a full discharge unfortunately. I'll try the BECM K16 reprogram next.

I have the defeat module as well - did not help.

Mats
 

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I had the “Service High Voltage Charging System” DIC message along with the check engine light last week. I just got it back from the dealer. I was prepared for it to be the bad battery coolant level sensor described in the old TSB PI0961. The service advisor told me that TSB does not exist anymore.

The codes it was throwing were P0AA6 and P1FFF. The paperwork says “Reprogram the HPCM2 and the BECM as per PI5920J”. I had left a copy of that TSB (PI5920J) along with the old one mentioned above on the passenger seat to help get them started in the right direction, lol.

Service was covered under the 8 year/100,000 mile VOLTEC warranty. I’ll be sad when that expires this spring.
 

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Hi - newest member with this problem. I think I've read every page and still have some questions.

Dealership reprogrammed after finding P1FFF and P0AA6 2 weeks ago. I don't know if they did hpcm2 and the BECM, but will find out today. SHVCS came back, and they now want $993 to replace the sensor of course. I'm handy with cars, but I'm no technician, so I have a few choices: 1) thinking about using a defeat plug, and then either buying a vcx nano to clear the SHVCS error or having my local shop do it for me, 2) trying to replace the sensor myself without replacing the coolant tank, and reprogram.

1) Does anyone have the part number for the sensor, and is there a walkthrough to replace?

2) Is the VCX easy enough to use? If so I'd much rather do this than go to the dealer every time, but has anyone posted instructions on doing this software update?

3) Since I already have the error, are these even my best options?

I've read a few accounts from members going through these steps and still being stumped, or having the defeat in place and the code coming back. I just want to take the most logical steps if someone can advise.

Thank you!
 

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Edit: Nvm WOT, I found an official document by accident, stating that the 5 V are indeed correct for the HPCM2 and my 3.563 V look like serious trouble
I have ~3.2v coming through my sensor harness, even after removing the pigtail to inspect the splice. If this is the only problem, I'm thinking I will use a 16k resistor to bring the current down to the acceptable volage range for the HPCM2 to read. This calculation is based on the 24.7k resistor values used by the defeat plugs to correct the sensor issue when running at 5v.
 
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