Scanner won't connect to ECU

tranzloop

Hiya new to this forum, so first up 'hello' to all. I hope to be able to contribute as well as quiz.

This one is the latter.

I have a 2011 370Z Roadster auto (32k miles) which recently went into 'limp'. Once switched off it would no longer start. I have two scanners, a wifi unit (Tacklife) attached to Torque Pro for Android and iCarsoft CR PLUS neither of which will talk to my ECU, both simply fail to acquire a connection over any of their pre-defined protocols.

I know that both scanners are working as they can connect happily to my other car.

Having disconnected the battery to try to 'reset' the ECU without success I called my breakdown provider (sorry, don't know what you call them in the U.S.) who was also unable to connect his scanner to the ECU. In the end I had the car recovered to my nearest Nissan High Performance dealer who told me that there was a problem with the battery. They replaced it, cleared the ECU and gave me the car back.

All was fine for about 200 miles and the exact same thing has happened again.

So, the first question to my learned peers on this forum: does anyone now of an ECU state where it simply fails or rejects connections?

Unfortunately I have not tried to connect to the ECU when the car is healthy so I don't know whether this car just won't talk to a non-Nissan authorised scanner or it won't talk because of this current problem...or, perhaps, because the ECU has been programmed to reject connections under certain conditions.

The car goes into Accessory mode fine, but when I try to start it or simply press START a second time, all dash lights come on, the engine cooling fan fires up and most of the dash warning lights illuminate. Very little works. I cannot even roll the windows up

Given that Nissan seemed to correct the problem temporarily with a new battery (which I have trickle charged to full) it seems logical that this is an electrical power problem, maybe not enough amps available to draw upon for ignition? However, I have tried a new, unused larger battery for my other car without success. This could, however, be because the ECU needs to be cleared which I cannot do.

For further consideration: About three days before the first incident, I accidentally left the lights on and flattened the battery. An embarrassing tale that I won't go in to My wife drove to where I was armed with jump leads and the car jumped fine. Could the jump have damaged something like the alternator perhaps? I have never heard of that myself, but it seems like it might be at least remotely possible.

Finally, if I have to have the car recovered back to Nissan again, does anyone know of a way to put the auto gearbox into neutral so I can roll it out of my garage?

Cheers all


P.S. Probably should mention that I am in the UK and it is a Zed manufactured for the UK domestic market