Fresh install - Limp mode - help?

[drew6]

Hey guys,

I've installed a nistune board into my BNR32 ECU yesterday. Having done a Megasquirt before this I thought for sure I could handle doing one chip... Not so sure anymore.

My car is now in limp mode and will not connect. I cannot figure this out. I checked for continuity between the bottom of the 28 pin socket and the top pins on the nistune chip and every pin has continuity. I checked for continuity between adjacent pins to make sure no solder bridges existed and none of them have continuity. I also check for continuity between the 4 pin CPU connector and the nistune board and again it checks out.

What gives?!

Unfortunately, like an absolute butcher, I managed to break off half of a pin on the stock chip when I was removing it (there was a small amount of solder left on one pin and I failed to realize this until it was too late) so I cannot check if the stock chip is working in my socket.

Does anyone have any ideas? Is there any other way of testing my nistune board or my ecu?

Appreciate any help I can get. I really need to get this thing up and driving again.

[nanook]

Double check for any damaged/fractured tracks around/leading to/from pins.

[Matt]

If you have a small amount of wire you could substitute the pin on the stock chip and try that in the socket after straightening all the legs out to at least see if it works with that chpi

[drew6]

Update:

The stock EPROM chip wasn't as damaged as I thought as when I installed the chip the pin was long enough to still make contact (verified with multimeter). I installed the stock chip and no change. Still in limp mode. I then took the time to ensure continuity between the 28 pin socket to the nearest component on the board. (IE I traced each track to the nearest component and cleaned off the thermal coding to test it) Every single circuit showed continuity from the socket to nearest component. And again no solder bridges between circuits.

I'm baffled. This should be working.

[bachig24u]

run around the top (chip side) pins with solder again as you may have damaged a through hole tube.

sometimes during testing everything has continuity because you're pushing down on the pin to get a contact.

[drew6]

Ok, so I've spent more time on this.

I've checked continuity for everything single thing I've touched. All check out. I checked continuity on stock EPROM (very gentle ensuring not to press down on the pins to make a temporary contact) to the board an it checks out. So one of two things happened:

1) My stock EPROM got damaged somehow.. Be it heat, static or somthing.

2) Some other component on my ECU got damaged during the install. Not sure how that could have happened though.

I have no idea where to go from here....

[nanook]

You need to find another ECU that would be the easiest way to proceed from here, will give you a clear result but cost $$$

[Matt]

You can send it this way for me to have a look at. Have a good history of fixing bad installs

I'll normally do what you have done which is try the stock chip but will also check the address lines function on the socket, and VCC / GND have correct power and then check the /OE and /CE lines are clocking

After that data lines from the chip are checked at the MCU chip

[Eric]

have you also checked for shorts between (2) pins ?

[drew6]

Eric, yes I have checked for a short and have found nothing.

Matt, I appreciate the offer but I am on the east cost of Canada. By the time I send it to you and get it back plus pay for your time I could easily get another ECU.

At this point I guess my only other option is to purchase another ECU and try it again... Which is very unfortunate as I purchased this ECU for the sole purpose nistune as I was using an R33 ECU previously. The only thing that sticks out to me is when I purchased this ECU I was told by the seller that he was having an issue with a high idle. I've only ever used this ECU on my freshly rebuilt engine and I too was having a high idle (1400 rpm) that never exisited before the rebuild. I was blaming it on an elusive vacuum leak but now it has me thinking this ECU may have been buggered from the start and me taking it apart might have pushed it over the edge. I don't know.

Any thoughts?

[Matt]

Testing the ECU prior to installing the board is generally recommended. That way you can confirm the consult port works and PC is talking to the ECU. This helps if there is an installation problem later on

Agreed from Canada the postage is going to be at least $40AUD each way

High idle if using an Z32 ECU in an R33 may be related possibly to FICD wiring to the ECU if you are using a Series 2 R33

[drew6]

UPDATE:

I just got my new ECU and everything is now working great!

Thanks for all the help.