84dime

Just rebuild my GF's 98 civic dx and now im getting a p0720 code. It amuses me how im getting a transmission code when i didnt even touch the tranny (left it in the car). Can someone explain why im getting this code or what steps i should take to fix it? I dont even know where the countershaft speed sensor is so that info would be appreciated as well. Thanks guys.

Former User

Is it unplugged? It has a 2P connector.

84dime

Just checked and it is not corroded or unplugged.

Any other reason this would happen?

Before i rebuilt the engine i never seen that code, but my first drive after the rebuild that code popped so i erased it and it comes back after about 2 blocks.

Any ideas? Thanks

Former User

Original ECU?

Check two wires for an open. You may have broken one or both during the swap.

84dime

How do i test these wires? Continuity check? If so do you know the pinout for these wires? Thanks

84dime

Bump, how do i test this sensor? Thanks

honda_lx

I have this same problem and inside my connector closest to the passenger side windshield wiper is this.

http://farm8.staticflickr.com/7009/6...d37f2d8c5a.jpg

(notice how the white ends are all black)

I suppose it's definitely an open circuit, signs of overheating? I'm not really electrical person, how can I check for my open circuits?

John Paul

i had the same issue after changing one of the engine gaskets, did you ever resolve this issue?