Micra K11 Key Not Recog PART 2

The key not being recognised - that problem is back now.

Had 5 clear days after being fixed by a mobile locksmith when the key was re programmed.

Anybody any ideas on what the faulty component could be now.
Suspect the Ignition Immobiliser transponder in the steering column.

Would appreciate any pointers

TIA

Danny

Its NATS 2
- so dont know if there are any immob
by pass solutions available?

anybody?

Danny

Edit - Duplicated message

@Frank2

OK, its NATs 2 and 4 wire immobiliser part number 28590 C9915 Siemens 5WK4 594

Pic attached

The above ^^^^ unit is from Feb 1998 registered Micra K11.
Its a 4 wire NATS2.

Also got a unit from a scrapee. Also for 1998 year Micra. Unfortunately the connector was totally different and so was the black box which was much bigger. Black box was twice as big as the one shown in the picture above. The first five characters of the part number were same though ie 28590

Anybody with experience of replacing above units.

Danny

Here is a close up of above picture

Here is a pic of the two immob units

Incorrect one is 8pin plug

Correct one is 4 pin plug, 4wire

http://spidometrs.ru/s2/download/nissan_manual.pdf

http://www.direct-keys.co.uk/Immo Sevice.htm

the box probably contains the electronics to drive the coil and decode the key code , so the box must get passed a signal to tell it to read the key , and then that key info is passed back to the ECU which then decides if the car starts . I would think the ECU would power up , do a self check , read the key , and then start the engine ??
I would think the system can work as suggested by the 5 day fix , so something must be upsetting it , ie water ingress , poor joint ( ie earthing point ? ) which is upsetting the signals ..

a google search on "bl-160 nats 5 circuit signals" brings up info

Mike

Thx for the info and the links.
This will help with sorting it.
I will be checking earthing points.
I've checked for water ingress all around.
There isnt any that I can see.

I will be reading this over the weekend.

From other material I read, it appears that 3 units have to be recoded together. ie key, immob and ecu. So I dont know how some postal service are offering to recode your key and immob by post(but without ECU). Maybe they are diff systems.

I am also finding that there are not many mobile key locksmiths about in my area and those outside are not willing to travel. Is there a directory of these guys or a trade association?

Danny

just had a look at my car (2000 Super ) , the nats key gets read once the key has been turned to pre start . ie the ECL lights up , then the Nats led stops flashing . Also tried measuring what goes on with a compass , and the magnet detector , etc on my smart phone but had no luck .

update . just used a current tracer to confirm that as soon as the ECL lights up , a single pulse is detected around the key which must be when the key is read . So if you can get hold of a current tracer you can confirm if an attempt is being made to read the key !!!

i used one of these..
http://www.sellbuyclassifieds.com/l.../hp-547a-current-tracer-probe-25-shelton.html

Update...

The car is working for now.

But its not much better because although the engine starts,
the key has to be pretty close to antenna ring to detect the key code.

Not like before - just insert the key and drive off.

Have also tried a scrappies antenna immobiliser!
This would not recode for some reason.

Would like to hear from others if they have experienced this. This would indicate that its the antenna immobiliser thats faulty and a brand new unit may sort this problem.

Will just try it for a few days to see how it pans out.

Mike

the compass wont detect the magnetic pulse - possibly its too quick and short.

Danny

Mike R WROTE:

"just had a look at my car (2000 Super ) , the nats key gets read once the key has been turned to pre start . ie the ECL lights up , then the Nats led stops flashing . Also tried measuring what goes on with a compass , and the magnet detector , etc on my smart phone but had no luck .

update . just used a current tracer to confirm that as soon as the ECL lights up , a single pulse is detected around the key which must be when the key is read . So if you can get hold of a current tracer you can confirm if an attempt is being made to read the key !!!

i used one of these..

<a href="http://www.sellbuyclassifieds.com/l.../hp-547a-current-tracer-probe-25-shelton.html" title="http://www.sellbuyclassifieds.com/l.../hp-547a-current-tracer-probe-25-shelton.html" target="_blank">http://www.sellbuyclassifieds.com/l.../hp-547a-current-tracer-probe-25-shelton.html</a>

Click to expand...

Duplicated

"he key has to be pretty close to antenna ring to detect the key code."

I agree with this , I had a play with a "chipless " key and a "chipped" key and found that the chip had to be very carefully placed to let the "chipless " key start the car . even sticking the "chip" to the pickup ring did not work , it had to be in a certain place !!!

knowing what I know now , I would check out the wiring runs for looped wire , bad earths , poor connections , even the possibility of metal to metal joints making electrical noise , and ( daft as it sounds ) that the pickup ring is properly seated to ensure it focuses the radio signals properly onto the key .

Also noticed that the device has SCI pin ( Serial Comms Interface ) which would suggets a lot of clocking is going on in order to transfer data to and from the ECU , this can be susceptible to outside interference which can cause mis clocking and corruption of data , again check wiring and earth points , possibly screen the supply wires with cooking foil , ( done this my self for the ECU !!! )

I dont know if you have a big bunch of keys hanging off the key but I avoid this my self as the weight strains the lock , plus I have heard it suggested the metal can upset the signals .

Mike R WROTE:
"knowing what I know now , I would check out the wiring runs for looped wire , bad earths , poor connections , even the possibility of metal to metal joints making electrical noise , and ( daft as it sounds ) that the pickup ring is properly seated to ensure it focuses the radio signals properly onto the key.

Also noticed that the device has SCI pin ( Serial Comms Interface ) which would suggets a lot of clocking is going on in order to transfer data to and from the ECU , this can be susceptible to outside interference which can cause mis clocking and corruption of data , again check wiring and earth points , possibly screen the supply wires with cooking foil , ( done this my self for the ECU !!! )

I dont know if you have a big bunch of keys hanging off the key but I avoid this my self as the weight strains the lock , plus I have heard it suggested the metal can upset the signals .

Click to expand...

Mike

Where are examples of places - looped wire, bad earth and poor connections? Just below the ignition barrel or also in the engine compartment? What is electrically the noisiest component or system near the immobiliser?

Screening the supply wires - did it make a difference?

Agreed about the bunch of keys - we had separated the car keys from a big bunch a while ago.

But the thing that puzzles me - at one time we did not worry about any of this. This would indicate that a immobiliser antenna or another component is degrading in performance. If we knew from Nissan records or common K11 problems, I would just swop for a "new" item. I found this part number of immob also being used on several other Nissans like Primera and such. So there must be lot of historical data about this part collected in the company archives.

Oddly there is lot more info on the Russian web - drawings and such. If I could only read!

Danny