Dean Fritz

I have found that everytime I change a parameter when editing my bin the checksum changes.(In Winbin) I know that Winbin does not do a checksum, but does Tuner cat do a checksum? Will I have a problem if it does not equal the same thats was amount that was there before editing. If so how can I correct it. Does the ECM look for the correct check sum?

NickG

The checksum is suppose to change when you change the data. That's the method the ECM uses to determine whether or not the eprom is corrupted or good. If you changed a data map, but didn't recalculate the checksum, then the ECM would interpret that as a bad eprom and go into limp home mode.

Nick

Craig Moates

Can you not suggest to the ECM not to bother with the checksum? I know on the '165 MAF code, setting byte 08 to 'AA' will disable checksum 'check'ing. However, I think some of the editors out there will perform the updates of the checksum (usually located at the beginning of the code) for you automatically. But yeah, if you don't have it right or disabled...limp away...

TRAXION

Not too sure about the others but TunerCat will change the checksum for you automatically.

Tim

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TRAXION's 1990 IROC-Z
Best Time = 12.532 @ 109.21mph (1.778 60')
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels. Stock Wheels. No Weight Reduction.
Gunning for NA 11's after installing Hooker LT Headers and reducing weight.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

383LPE

the AA works.

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Dan
LPE built 383 A/T Package