Something went nuts in 906a9

Stinky · Post by **Stinky** » Wed Jul 19, 2006 1:09 am

Not sure what exactly is happening here. I got home yesterday and the car was idling lean and acting strange when I let it sit at idle(maybe a seperate issue). Nistune seemed to be working fine. I played with the tp min for a while, played with the wideband inputs, and then shut it down. Started it back up to make sure everything was fine and then shut it down again. This morning I went to start the car and I got the dreaded fuel pump pulsing. I was able to get another rom in and get to the shop without an issue. Here's the read of the nvram chip. Something isnt right.

Matt · Post by **Matt** » Wed Jul 19, 2006 2:18 am

indeed something isn't right here....

the rom image is really funny. i've got a jump to BDB2 which should be BDB3

i've also got 6000 being set to 51 when it should be 79 (the write to 6000 was taken out of the latest patch code)

7210 - 7500 is corrupted and the patch code is completely gone. on the current boards the patch code is not protected from overwrite but the rest of the ecu image is

however i think the STK15C88 may be autostoring corruption. were you using the rev5 patch file here? i cant see any of my patch code here since its all gone!

what is strange is that 0000-3fff is affected. this shouldn't be touched since A14 should be tied high. can you please check pin 1 of the NVRAM is indeed buzzing out to VCC. the patch code in the first mirror image is also gone. that is not right. please reflash the chip using the 0.907a patch image file but make the lower half 0000-3fff all FF and only the rom image loaded in 4000-7fff of the nvram

i could put a STK15C88 in my ecu but we are not using these chips now due to these types of problems. the STK11C88 forunately only store when the STORE button is pressed. the 15s have a potential to autostore when we dont want it to

when you get the car not running right, please download the image immedately via nistune (if possible) so we can see where the problem is starting before it gets worse

Stinky · Post by **Stinky** » Wed Jul 19, 2006 3:21 am

I'll try to do some more playing around and see if I can replicate the problem.

Stinky · Post by **Stinky** » Sun Jul 23, 2006 4:24 pm

Matt wrote: can you please check pin 1 of the NVRAM is indeed buzzing out to VCC.

Which pin is Vcc? It buzzes to pin 27 on the ecu side.

Matt · Post by **Matt** » Mon Jul 24, 2006 1:14 am

VCC is pin 28
GND is pin 14

on the NVRAM pin 27 is /WE and pin 1 is A14

the /WE should have a pullup 10K resistor to VCC. if the line ever floats, the pullup will make it in active (pulling line low makes a write to the chip)

new boards for NVRAM will also have a pullup on /CE line (pin 20) just in case, since both /CE and /WE lines need to be low to activate a write. also having /WE low during chip poweron can cause corruption too

Stinky · Post by **Stinky** » Mon Jul 24, 2006 1:38 pm

Ok. Pin 1 on the nvram buzzes to pin 28 of the ecu with the nistune board in place. I also measure ~10k between nvram pin 27 and 28 because of the resistor you had us put in. Should I put in a resistor to pin 20 as you mentioned?

Matt · Post by **Matt** » Mon Jul 24, 2006 3:31 pm

we will just try without the extra resistor for now, because that is what i am running. i'll put the STK15C88 in also with this change (currently running STK11C88) and take a spare ecu just in case i bugger it and it auto stores in the middle of nowhere

Matt · Post by **Matt** » Thu Aug 10, 2006 10:13 pm

any more problems with this?