ECM missing diagnostic screw

Jun 18th, 2002, 04:08 AM

Hello there,

I was trying to make some O2 diagnostics on my 91' NX2000, so I dived to the ECM, but there was no mode switching screw. The ECM says it is A11-B70-BF7 and 23710 and 71y05 and #1307. And there is a big red 96 sign on it. It has got a nice tape covered hole where the srew usually is, it also has got the diagnostic led. But no way to activate it. Any idea ??

Thanks, Oscar

Black200SXSER · Jun 18th, 2002, 12:09 PM

it should be behind the tape..pop thru it and see if it is there

Jun 19th, 2002, 02:02 AM

Of sourse I have poped out the tape, in the resulting hole i have nice view on some IC and electronic stuff, but no thing to put my screwdriver into. My car is on of the first '91 nx2000, nissan is denying any possibility of missing screw. My glasses are OK

. It may be possible to switch modes through the consult port ????

Thanks a lot for your reply

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this is my ECM, view from top of the vehicle O-screw hole, o-led

Oscar

hpro123 · Jun 19th, 2002, 02:30 AM

Oscar, welcome to the wide world of Nissan ECUs.
Indeed, several 91-94 ECUs in Europe do not have the little diagnostic screw. Ours in Greece do not have them.

What can you do? I wish I knew.

The Consult port can be used for this purpose but you obviously need a Consult to do it (do you have access to one? Probably not since in this case you would not need the screw and you could retrieve all the info through the Consult.

Still, (if anyone knowledgeable watches this thread feel free to jump in at any time!) from close inspection of the place where the Screww should be, it seems that there are only 3 contacts where the "screw" potentiometer sits. It would be simple to just solder an Appropriate potentiometer there. The only problem is...What is "Appropriate" in our case?

Chris

Jun 19th, 2002, 02:54 AM

Thanks Cris,

You are right, I dont have an access to Consult. But never mind. I just wanted to measure O2 sensor, so I will need to dive under the car. I will try to get the pot value from nissan, I will let You know, if i§ll be successfull.

Oscar