My G35 was running perfectly when today it will not start. Alt goes on, lights, radio and touch screen powers up but speedometer etc screen does not come on. Car just sounds like it is weakly trying to turn over. Any suggestions on problem?

 

Start by cleaning the battery terminals and the wire lugs, both ends of the wire especially where the negative lug lands on the chassis next to the battery. If that doesn't fix the issue get your battery tested, and hydrometer if it's a refillable non-sealed type. If that doesn't fix have the cables tested for resistance to make sure they don't have a pinhole damage somewhere and the copper conductor is corroded. If that doesn't fix then the starter itself is failing and needs replaced.

-Clean batt term and wire lugs (both ends of each wire)
-Test battery
-Test cables
-Replace starter

In that order.

EDIT: Clean terminal lugs with a wire brush and apply an anti oxidation grease to lugs, auto parts houses carry the de-ox as well as places like Home Depot in the electrical section.

 

^^^^^^^^^^^

What he said but did you try jumper cables?

Call AAA and they can do all of the necessary tests, install a replacement battery if necessary, and if it is a starter problem send a flatbed truck to tow you to a dealer or one of their shops.

Telcoman