Dead in the garage - Codes

[97dyna]

2003 G35 won't start.
Diagnostic codes :
P1212
P1612
U1000
U1001
I jumped the gun and replaced the battery - (not it and the old one was good). I checked the battery terminals, grounds in the engine bay and the interior I could find. Several monthes ago replaced both cam sensors and the crank sensor. These codes have me baffled on what to do.
Any help would be appreciated!!

[audtatious]

http://www.nicoclub.com/FSM/G35/Sedan/2003/ec.pdf

P1212: (page 508) TCS COMMUNICATION LINE
U1000, U1001: (PAGE 142) CAN COMMUNICATION LINE

P1612: Nissan Anti Theft System (NATS) ; This code means you have a chip issue with your key. In effect the anti-theft immobilizer system is not reading your car keys. This must be repaired at the dealer as they will have to reprogram the immobilizer to your keys.

The top two indicate a open connector or break/short in the communication system. This could also be due to a bad battery, poor grounds, etc. The NATS issue could also be caused by the communication issue within the car and not a problem with the keys.

P1212 says to run the tests via the U-codes on page 142 of the linked pdf. Start there and see if that gets you in a proper direction.

[97dyna]

Can someone tell me where the steer steering column ground is? I have the lower panel out beneath the steering wheel and nearly see to the back of the instrument cluster. I see nothing....

I haven't tried to find the ECM ground on the passenger side yet. Hopefully it will be more obvious.

Thanks in advance!

[audtatious]

I doubt anyone will know offhand. Dig through the FSM and you may find it: http://www.nicoclub.com/FSM/G35/Sedan/2003/

[97dyna]

Everything I have read points to an open ground. I have cleaned and tightened the engine bay grounds that I can see from above. Pulled panels and looked for grounds under the dash, both sides, did not find any grounds. Pulled the radio, from the dash, nothing there. I'm going to look under the car today.