ok..here is the deal. i have had the car on the road for over a month, driven it every couple days with no signs of this problem until today.

i start the car, and the SES light flashes as if there was no EPROM in the ECM. this is a VERY intermittent problem. it happened a few times last fall, but it seemed to have went away. it is a custom chip by the way.

today, after having the SES strobe problem, i turned it off, and turned it on again, and it was fine. then, a couple minutes later, i started it again, and it was doing it again (flashing).

it seems to me that this is either totally unpredictable, or there is something causing it that only happens once in a while. today, the car was out in the sun for a while (its usually in the garage) and was pretty hot inside. this usually doesnt happen. does high heat have any effect on the EPROM? it is seated correctly, so i know that isnt the problem.

any ideas? just trying to get to the bottom of this.

by the way..i burned a duplicate chip last year, and the same thing happened. i figured maybe i had a "bad" chip or maybe a bad data transfer or something.

thanks...

-brian

 

I had an eprom that started flashing after many miles of
driving . I "think" that what happened is that eccessive heat
caused a few of the bin addresses to change and then the
eprom would no longer pass the checksum test. I was using
an eprom with a lower heat range.

Try entering AA in the mask I.D. location in the bin file
or try recalculating the checksum in your bin editor and reburning
the chip.

You also could try a different brand of chip.
I have also had good luck with the chips that that are GM's ecm from the factory.

I also use chips out old telephone systems that work well.



BIGED

 

this is why I stopped using 2732's and bought one of Craig Moates' 29C256 adapters. After so much use my 2732's were getting flaky. They would "cut out" while I was driving...which really sucks.

If it's a chip that you've programmed on alot then I bet it's time to replace it.

 

Please also try lengthening the program pulse. For 2732's, the proper program pulse length is about 50msec. (this is a general statement - check the datasheet for your particular device)

~50msec X 4096 locations equals ~3.5 minutes to program a 2732 properly.

To change the programming pulse in the dos version of pocket programmer, menu 88 and option 6 will let you chnage the pulse time (its a hidden menu).

EdB