erratic tach reading

Jhill

Not being a Nissan tech I can't say without a doubt but I would be really surprised if it were not the cluster itself. The reason I say this is today's cars all use networking with multiple modules and your cluster will be one of those modules. So your looking at power, ground, can hi, can lo, possibly tied in with body can system as well and that is about for wiring. If all your other readings are correct then the cluster itself has in internal issue that you won't be able to service. Will have to go to dealer for new cluster, programming of mi etc.