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What happens when the battery goes flat in your Nvram
The one in my VX drag car would be about 10 years old and it did sit for a few years while I had the motor out of it
I’m a bit worried the car won’t start one day

It will be wiped

yep, if your not tuning it anymore you should transfer the tune to an eeprom in a socket on a memcal. it is convenient to leave the nvrams in the car but they're really a tuning tool and not designed to be permanent. Theres a few threads about how to do this around, or you should post a request and ask if someone can do it for you. Either way make sure you have a complete copy of the bin your pc as a backup (eg ose flash tool -> get bin for $11p and $12p)

I make changes all the time depending on track conditions or changes to the car

Can I get another Nvram chip or do I have to change/buy a new chip and adapter

you can get another DS1245Y-70IND+ from a respected reseller like element14 or mouser, program it in a gq4x4 or minipro programmer (or equivalent) with a stacked bin from the 12p zip file (assuming 12p) and when its in the car upload your cal again over aldl. ebay ds1245y chips are probably clones that are no good.

antus wrote:you can get another DS1245Y-70IND+ from a respected reseller like element14 or mouser, program it in a gq4x4 or minipro programmer (or equivalent) with a stacked bin from the 12p zip file (assuming 12p) and when its in the car upload your cal again over aldl. ebay ds1245y chips are probably clones that are no good.

Oops. So it's not just "plug in and go" (after reuploading cal)?

I had been considering this because I have no ability to program a Memcal.
But without a gq4x4 or minipro programmer or ability to do so with a new DS1245Y-70IND+ I'd be hooped again!

Just been reviewing this as mine are coming up on 10 years in 2023-2024 in my two cars...

thats correct, they ship blank as an empty memory chip and you need to get the operating system on there first because the ecm or pcm needs the operating system to be alive and to communicate over aldl. plugging an empty chip in is eqivalent to no chip at all.

I use mine for tuning only and have all my tune files backed up. All my cars have an EEPROM socketed in them.

My NVRAM is from 2011 and still working well but I also should consider getting a spare. I have heard some die at about that 10 year mark, others have lasted over 30 years.

I have seen them die at 8 years, 10 is quoted and you can run them full time in your car but they designed to be used for tuning, then put the tune on an eprom or eeprom in a memcal once youre done as that will normally last forever.