As reported in a previous post, I put my instrument cluster into Mode 4 self-test which provides a digital engine RPM readout. Then I waited for the "yips" to occur--with my tach falling to zero.

And so it did (i.e. the tach fell to zero)--but my digital engine RPM display also fell to zero--indicating the loss of the TNA (engine speed signal) from the Base Module (N16/1).

So, I'm forgetting about any possible instrument cluster problems and focusing on Base Module.

The OBD I diagnostics have been telling me that the TNA signal from the Base Module is bad. Of course, I don't want to believe that--because of the cost of the Base Module. I've pretty much exhausted other possibilities and am back to the Base Module as the likely culprit.

Anybody know where/how to get Base Module repaired or exchanged? I hope it's not a throw-away item!