HV Battery Issues P0A80 / Fan Concerns

Posting this for a buddy of mine who isnt internet savvy but came to me experiencing some issues and codes on this 2012. So this is NOT a repost to my own P0A80 thread and totally separate.

Car: 2012
Miles: 206k
Maintenance: Unknown
HV Battery: Appears Original & all S/N matching

My buddy found out I was having a similar issue with my 15 that had experienced the P0A80 code so he asked for help. He purchased the car 2 years ago from original owner and has only done basic maintenance like Oil and brakes.I was surprised when he said he had been driving with the code on for approx 1 year already! When I initially checked the car out, the YTOD was on the dash and codes came back as P0A80 as Current / Pending / History. We checked the block voltages and all 14 were in the mid 16v range with no major variance. +/- 0.2.

What we checked on manually:
1. Mild corrosion found at busbars
2. Static voltage averaged 7.9v on all 28 cells
3. Load voltage using headlight bulb drawing 6/7 amps at 2 min discharge rate averaged 0.2-0.3v discharge (all staying well above 7.5v
4. Battery fan was extremely blocked with debris. Looked like the lint sheet you remove from a dryer screen after use.
5. All connectors near battery and PCM were clean and not corroded.

What we did:
1. Replaced all busbars and nuts with new nickel plated ones
2. Ensured continuity on each pin with connector at busbar and all pins verified contact
3. Cleaned the fan thoroughly with a brush
4. Torqued each busbar nut at manual specified 48 in. lbs.
5. Verified all connectors once again and all good

What occured after:
1. Car turned on and codes were still on. Car would also NOT shut off after 12 sec idle.
2. Codes erased BUT came back on 5 seconds later
3. Codes now were P0A80 and a P0B42 (looked up last code and called out busbar connector resistance high)
4. Checked all busbar wiring and found one of the rear had a hairline crack at head where it mates to the busbar (most likely happen when torquing it since the heads move slightly). Repaired it to ensure good contact.
5. After putting it all back together, dash lights and codes disappeared and car shut off after 12 secs like they do normally.
6. I then verified the HV battery fan was working and it was on and turning fine
7. I attempted to do an actuation test on my scanner to test the multiple speeds of the fan and it did not change or turn off when instructing it to do via scanner. I am aware of the Gen 2 fans changing speeds and get louder when battery is warmer but unsure if these Gen 3’s are the same which I would assume so. Fan just remained on at one single speed.
8. Rechecked for codes and none present.
9. My buddy drove the car home and light did NOT come back on and he felt the car running great
10. Today, the YTOD and CEL came back on after a short drive. We planned on rescanning the car tomorrow to see what the codes are.

Any ideas on this? This is def different than my P0A80 dilemma as my car does not have the YTOD of CEL on and only shows the code as permanent so not sure what to check next.

 

Whats that suppose to mean?