I have a 1996 Honda Civic hatchback. The following seemingly unrelated problems all occurred at once, so presumably have some relationship to each other, although I have no idea what it is. Any ideas?[/align][/align]1) Speedometer suddenly stopped functioning. Now it either sits at zero or bounces up to 80 or 90 at random times.[/align]2) All lights (dash, headlights, interior) are constantly pulsating while the engine is running (dim-normal-dim-normal-dim-etc.). The rateofpulsating is not affected by RPMs. There is also a faint squeek from engine compartment near steering column that occurs in sync with the pulsating.[/align]3) Check engine light came on. The diagnostic trouble codes indicate bad O2 sensors.[/align][/align]Thanks for any help.[/align]

 

I have a 1998 Honda Civic LX. Have not yet checked CEL code, but I now have exactly the same problems: pulsating lights, cel on, speedometer at zero and odometer does not work. I've been told to check for blown fuse, bad battery or bad alternator.

 

1) Check whether fuse #15 in the under-dash fuse/relay box is blown (see picture).

2) Many have reported that fuse #15 blows because the wire harness coming from the Vehicle Speed Sensor (VSS) and oxygen sensor shorts out on the intake manifold.

[IMG]local://upfiles/25538/E7BC7A7F2D4A49D5BEA939FF9DCFEE66.jpg[/IMG]

 

Once again, this forum has saved me a bundle of repair money. The #15 fuse was blown; I replaced it and reset the CEL; everything works fine. Two years ago, I used this forum to find out how to check the CEL codes, and replaced a bad O2 sensor myself. Thanks for the advice. Just one thought: why does the #15 fuse blow; what causes the short as you suggested?

 

I believe the answer is a combination of rubbing on and heat from the manifold. If fuse #15 blows again, you should carefully inspect these wire harnesses.

 

The wires from the o2 sensors i can find, but where is the wiring harness/wires for the VSS, so that i can inspect the same? Thanks again

 

The VSS sensor sits on top of the transmission. Pictures I recently posted of the sensor in my 97 Civic 5-speed may help:

https://www.hondacivicforum.com/m_52..._2/key_/tm.htm

 

Unfortunately, after driving the car about 200 miles the past two days, the #15 fuse blew again, causing the above reported problems. The codes from the CEL are 20, 41, 65, apparently all dealing with o2 heater sensors and electric load sensor. Any suggestions?

 

You have an electrical short in one or more of those circuits. Locating the short is key to solving the problem. Look for burnt or damaged wires and wire harnesses.

 

The wiring harness located underneath the intake manifold was indeed the culprit for causing the #15 fuse to continue to blow (causing all of the above mentioned problems). One of the wires had rubbed through to the metal causing a short. Problem solved. Thanks.