electrical problems?

[mattus72]

I have a 93 ex civic that started to develope some problems a few weeks ago. all problems are off and on. 1st about half the time starting it will turn slowly for a few seconds sounding like the battery is dying but it will finally start. the 2nd issue is every now and then while driving the tachometer and speedometer will both simultaneously drop to zero but the motor itself is running just fine with no variance in rpms or speed. and the last problem is the tach and speedometer do the same thing occasionaly when using the turn signals, so if anyone has any answers that would be the jam. thanks everyone

 

[LS_VTEC]

Wiring issue and/or inoperative VSS (vehicle speed sensor).

Check starting/charging system. Can be discharging battery, or faulty alternator.

 

[rdomeck]

Maybe start with checking some grounds. Check the chassis to engine ground in the right front of th engine bay. It's a bigger cable that I believe will be black with a yellow tracer. Also there is probably one from the valve cover to the radiator support. Most problems like that can be traced back to grounds. If you have access to a Hanes or Chiltons manual, they usually have ground circuit wiring diagrams. You may also check your battery connections and maybe put a volt meter on your battery with your engine running. You may have an alternator going bad. You should have around 13.8 volts. Sometimes overcharging can make funny things happen. Anything above 14.5 volt and I would worry. Anything below 12.8 and I would also worry.

Hope this helps

 

[LS_VTEC]

Checking charging system voltage (when running) is tricky, especially with just a multi-meter. You need to put a load on the engine, and then another load on the electrical system, I.E. headlights, to make an educated decision on the charging systems performance.

 

[rdomeck]

Puttin a test meter across the batter leads is a very easy way to determine if you charging system is working. A battery will read around 12.8 volts when it is fully charged and the engine is not running. With the engine running it should read around 13.8. I don't care what kind of car it is. Having the lights or anything else on should pull a load from your alternator and not your battery. So having those things on isn't neccessary. You can to see if you have a weak alternator, but to find out if it's putting out anything just put a test meter on the battery with the engine not running and when it's running.

Try it on a vehicle that you know is in good working condition and you will see....