I've been going through a hell of a time with my 2014 Honda Civic EX with the 1.8-liter I4 engine, automatic CVT transmission and 160,000 miles.. Here's the list of everything thats happened to it so far in the past 2 months to where we are now. (Speedometer will randomly show 0 even at speed.) Does anyone know what could be causing this?

1. Drive belt in the CVT came apart. Verified by local shop and dealership. Local shop replaced the transmission and both CV axles.
   
2. After fix was driving and after sitting at a stop for a few minutes the speedometer stopped working. Would only say 0. After getting it home and it sitting for a bit it started working again. No codes or anything
   
3. Took it back to the shop, with no codes and it behaving itself they gave it back and said to bring it back when it throws a code.
   
4. Couple days later, does it again. This time it throws a code P0502 Vehicle Speeed Sensor A no signal. So I take it back to the shop. They check the sensor, replace it, and also replace both the ABS sensors since they said they disconnected the VSS sensor and the speedometer was still working.
   
5. So now its been about 2 weeks since then and this morning it decided to do it again, this time no engine light, tried driving it for a bit to get it to throw one and no luck. I don't really know where to go from here.
   

Every time its happened after idling for a couple minutes (drive thru, long light)

 

I'd take videos since the problem is intermittent. You'll have to have patience with the mechanic since it they can only spend so much time with it before the labor cost makes no sense.

I know nothing specific about these, but if I were to try to tackle this issue I'd try to do my own datalogging to pinpoint the problem. 2014 I assume has canbus. So I'd get some canbus analyzer that has a profile built-in for your car. That way you can drive around with a laptop and visibly see what the ECU is seeing. I'd try to find out how the car determines speed to begin with. Maybe the dealer can help, that's a very technical question tho. Is speed from VSS in trans, wheel speed, gps, or a combination of the 3? Is the ECU solely responsible for speed signal generation on the canbus or does the dash pull the info directly off the canbus stream (from the sensor reporting).

 

I got a video for them last time it happened of it just having the speedometer bounce between 0 and 1 while actual speed was somewhere around 40. Currently they think it might be the ABS modulator, but they have not verified that.