for the past 6 months or so my speedometer hasnt worked, when it stopped it did this jumping thing for a while where even if i wasnt moving it would say i was going really fast and just bouncing around. i swapped out speed sensor and guage cluster what could it be. using the old iphone speedometer is really getting old?

 

Broken speedo cable or broken speedometer.

 

I changed gauge cluster. And how do I check the speedo cable