Honda Civic Dx 1996, The check engine light came on, the speedometer stopped working, and the lights were pulsating. No other noise or problem, the car still runs fine. All interior and exterior lights pulsate, fading in strength and then going back to normal.

Disconnecting any sensor will cause a non working car to work suddenly.I would check two things. 1. The Transmission control module- vary rare issue. 2. the ignition control module. These break down a lot in Honda's. In the 96-98 model of the civic, the dash uses the tach built into the ignition control module. the 99-00 model doesn't use the ICM tach signal, but uses the same module. Test your ICM with a digital multi meter ($5 @ harbor frieght), before dropping $60- 140 on one.

Code 17 speed sensor. Does speedometer work? there is an assembly at the top right of the transmission from which a cable runs to the speedometer. A non working speedometer isn't a massive failure and you can Google how to fix it.

More info needed. Is this a hatch back, sedan, or CRX? Is the odometer mechanical [old style] or digital [LCD numbers] The vehicle speed sensor [located behind the speedometer in the instrument cluster] drives both the speedometer and the odometer [mileage meter]. It sounds like an electric problem in the instrument cluster. Remove the instrument cluster and take it to your local speedometer repair shop. Look in the yellow pages for them. Or simply buy and install a used instrument cluster from a junk yard.

if your speedometer is working,and the odometer is not,you will need to have the odometer replaced for it works off the speedometer

it is more than likely a short in the headlight switch. also try the dimmer switch on the dash for the dash lights.

Your cars speedometer has a broken or frayed cable replace it the Tach is separate from the speedometer/odometer and will work on its own

alternator on its way out. replace alternator bushing.

Had this issue did you replace the exhaust

Go to the nearest auto zone an ask to borrow the OBD-II diagnostic tool.

When you get the code, you can look it up =>
http://www.obd-codes.com/

Look on the wiring harness it plugs in on top of the transmission
make sure all the wires are together. If every thing is ok with the wiring, The sensor is the only thing it could be. A gook used spedometer sensor from the junk yard will work this sensor dosent take a lot of abuse so a good used one will be cheap and work just fine. This is a job you can do your self and save a lot of money. I had the same problem with my 95 civic