98 Toyota Corolla not shifting into 2nd?

Intermittently has reverse and 1st, but won't shift into 2nd gear. When problem occurs speedometer drops to 0. Code for vehicle speed sensor. This vehicle has a VSS on transaxle. VSS is an analog sensor that sends signal to instrument cluster, which converts it to a square wave and sends to PCM. Looking for someone who has a lot of experience with Toyotas to give advice if it's usually the VSS or instrument cluster. I know how to diagnose this condition but whenever I have vehicle I cannot get it to act up. Just asking if it's more common for speed sensor or instrument cluster. I understand wiring or pcm could also be an issue but doens't seem very likely to me.