Engine swap - No start condition, NATS?

Hi Folks,

Am posting from the UK as it seems you guys down under have far more Patrols than we do here in blighty, so seems a better idea to tap your knowledge.

Anyway, to my issue.

I've a friend that has two patrols, both the 3.0 litre diesels. One was rotten but had a good engine, the other packed up soon after the rotten one was taken off the road as the engine had seized. Said friend then took the rotten one and the seized engine one to a garage for them to swap the engines over, make one good one out of two he thought!

The issue is that the engines have now been swapped but the now supposed good vehicle won't start. Garage have washed their hands of it after trying to get it going... It's been sat for a while gathering dust, it's only now that I've got to the end of my job list and I'd said that I'd have a poke about and see if I can get it going....

As far as I'm aware, the engine, ECU and key are all from the same rotten vehicle, but now in the one which had the seized engine. I'm pretty happy that they have primed up the fuel system as fuel is getting to the pump, so not a fuel starvation issue.

On cranking the engine the red NATS light stays on constantly on the dashboard. When not cranking it is flashing.

I'm under the impression that the NATS system is not too happy about this new engine and ECU. Is there anything else that needs to be swapped over for the engine to "think" it's still in the rotten vehicle, when in reality it's got a new home?

Any help would be much appreciated.


Regards,

Matt

Welcome Matt. 3lt is not my strong suit so grain or salt required. In some 3lt the NATS is a5 the ignition. In thr ring around the ignition and takes a sensor from the key. These can fail. Did you swap the key surround as well as the key?

Hi MudRunner,

Thanks for your prompt response.

Not sure about the ring around the ignition, will have to check tomorrow.

Annoyingly the garage that did the swap did not mark up any of the keys or parts so It's going to be a bit of trial and error to work out which bits belonged to which vehicle, electronics wise

Also, are you aware of any software available for the DIY'er to troubleshoot EML's etc?

Coming from a Landrover and VW background, DIY tools are readily available..

There is a way to bridge contacts in the OBD plug to get the codes to show via flashing engine light. I don't remember it but the info should be somewhere here on the forum.
That will likely tell you what the issue is, especially if it's NATS..

On my 3l DI the red flashing light goes out when the key is switched to "ignition" (prior to cranking). As far as I am aware if that does not happen the NATS has not switched off and the immobiliser is still on. The key has a chip in it which is picked up by a sensor around the ignition which then talks to the ecu. Not sure if the sensor has to be matched to the key or if it is just a receiver. However, the ECU and key chip have to be matched.

Matt,
My NATS understanding is limited but as @BillsGU stated, my CRD NATS indicator behave the same (always flashes @ 3 sec intervals) until key/barrel is switched to "ignition/on" (prior to cranking) and no illumination while eng cranking and running.

Observations:

Beware the NATS coil is very delicate so care is needed when removing steering column shroud. Never removed coil but have had to repair it as Nissan stuffed it doing a dash replacement.

I had a need to get a new key and this new key plus originals had to be all programmed / coded together by Nissan Dealer.

I have a spare key that is just a plain key for door entry and is not coded. When using it in the ignition switch/barrel, the NATS led flashes as above until key is turned to "ignition/on" and for cranking, the NATS led stays solid.

I recall when I had a ECU remapped(live tune), the tuner used a second ECU (off the shelf) of known parameter set points and was tested in my vehicle, the tuner did additional parameter changes and when satisfied he downloaded the changed parameters from this second ECU and uploaded to my ECU. Unless he disabled the NATS functionality within ECU, the NATS functioned correctly and same with both ECUs.

Think you may have to use original key from the parent vehicle as could be linked to coil sensor and try with both ECUs.

Alternatively go to a Nissan outlet/approved service agency and get them to code the keys to vehicle.

Hope it helps some mate.

Ok, Update.

Under the steering wheel and column it's all in bits, not ALL, but enough to start swapping stuff out.

I have two keys and two remote fobs.

One ECU which sits on the left hand side of the drivers foot well, and another box of tricks that sits on the right hand side of the foot well, I believe this is called an ECU relay. Will try and hunt down the other ECU tomorrow.

I also have two ring thingys that go around the ignition barrel.

Just for clarity for future posts, the rotten one is the Red vehicle, and the seized engine one is the Silver vehicle - Red engine is now in Silver.

Silver's ignition barrel is the original one that Silver came with, obviously only one key will work in it. I have tried both remote locking fobs connected to Silvers key with both ignition barrel thingys, same ECU and both ECU relays. As far as that is concerned, I believe that I have covered all combinations.

One thing that occurred to me though is that the transponder chip for either vehicle that is linked to the ring around the ignition barrel are actually in the KEY portion, not the fob portion. So I've been continually using the Silver key's transponder with all configurations as the red key obviously won't turn the ignition barrel. Tomorrow's job is to swap over the transponder chips in the keys and try all combinations again in Silver.

In all the above combinations, the NATS light would be flashing, then as soon as ignition is "on" ready for cranking, the NATS light is solid. Tried a very short crank and it does turn over which is a good start - Been sat for at least a year!!

An interesting point about the two ECU's used for tuning your truck. Seems as though the immobiliser portion of the Nissan is independent of the ECU meaning you can swap out ECU's as you like?

Another question though - Where is the alarm/central locking ECU/box of tricks..? This may not have been swapped over from the red rotten one to the Silver one? Don't know where it hides so if anyone knows, please let me know as that might be the last piece of the puzzle.

If I exhaust all options in the Silver vehicle, I may go back to the red one(which is engineless) and just try with the various combinations of ECU, relay, ignition barrel ring thingy and see if I can get a combination to work with the NATS light going out.

Just for reference, I found this video on YouTube showing that the transponder chip is indeed coded to the ring around the ignition barrel.

Nissan Almera, Primera, Skystar, Patrol Key Programming using "ZFH-C09 UNIVERSAL CABLE"

https://www.youtube.com/watch?v=Ud43Y1yDNo0

OK. Lots to look at. Forget about the fob for now. It only locks and unlocks the doors. You don't need it to start the car or disarm the NATS. Worry about getting the key/ecu right and then the fob is relatively easy to code to the ecu (there are posts on here to explain how to do it).