I have a 1990 honda accord 2 door ex and the speedpmeter don't work and would like to know how I can tell if it is the whole tach that is needs to replaced or a quick fix and all help would be nice

I have replaced all the fuse in the box and under the dash and that's about it

Not sure if your car has a speed sensor; that may be the problem.

If the odometer and trip meter work, but the speedometer does not, inspect the speedometer, then the printed circuit board.

Both trip and odometer don't work along with the speedpmeter and this is my firls honda I'm a Mitsubishi guy lol

Since the speedometer, odometer, and trip meter do not work:

. Test all underdash fuses with a test light or multimeter. Be very thorough.

. Examine and clean the Variable Speed Sensor (VSS) connector on the transmission.

. Clean the main ECM ground, located on the thermostat housing, since the VSS grounds via the ECM.

. Replace the VSS, if the problem persists.

That's the best I can do.

OK thanks will do that also the engine light came on and I read the code 41 which is 41 Primary oxygen sensor heater that means I should replace the o2 sensor or something elss?

Here's how to replace the Oxygen Sensor:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563.html#post223376

Stay away from Bosch sensors.

Thanks will let you know how it went and thanks for all your help