Sergeant Larson

98 civic lx recent purchase 200,000 miles. Picked up car in WI and drove home to IA about 300 miles. En route the battery light came came on and around 30 mins later the whole system shut down. Pulled over thinking the worst, but it restarted without hesitation. No more battery light after that until about 4 hrs later and again the car just shut down. Restarted fine and drove the last hr without issue but the charge light was staying on constant. Checked volts at home on battery 14.6. WTF. Continued driving it to work last week and light was on constant. SRS light also started turning on. Occasional shut down but always restarted. Throughout the week I started doing all the stuff a non mechanic would: Checked batt terminals, fuses, ground connections, searched for exposed wires/evidence of arching. Nothing. During this I noticed that most of the elec system appeared new: batt, ground wire on batt, alt, and underhood fuses, relays etc. Sat night i drove for about 20 mins and dash dials danced, lights went dim, warning lights all went out but car continued on batt power until it finally shut down about 3 mi from home. Came back about 9 hrs later ready to yank it home, but it started and drove home fine, but without warning lights so I assume I was on batt power again. Our construction company shop mech ran some tests couldnt find any obvious faults with batt, alt, etc. Other info: car has aftermarket stereo(Sony Xplode appears same era as car) which im going to be pulling to check wiring. Right blinker is more interesting: when headlights are off it fast blinks like a bulb is dead, when lights are on it slow blinks but either way both bulbs are working. Not sure if the blinker or stereo are related, but thought it was worth mentioning. Any help is appreciated.

theYBLEGAL

Usually that's bad grounds, or a bad connection at the alternator charge terminal.

You could run a couple wires from your battery to your cabin, to an accessible place, and monitor your voltage when the problem happens.

mk378

The fuse 15 problem can cause the battery light to come on falsely. Check those wires before something worse happens.

If the charging system really were failing, the battery would run down completely until the car stalls-- but you would not be able to restart it-- the battery would be dead.

So something else is causing the stalling. Seem to be several problems with this car.

Check the grounds on the front corner light.

civicservice

What's the voltage at the alternator? How does battery voltage change from off to cranking to idle and under acceleration? Do you get 14.6 volts continuously under all conditions?

Sergeant Larson

what is a fuse 15 problem? i replaced the alternator fuse under the dash 7.5A. i dont think the chrge system was failing initially, it felt like it was shorting out. im guessing whatever was causing it couldve fried the alt saturday night. checked lighting ground front passenger side-mild green corrosion, cleaned and reconnected but still blinking the same.😢

Sergeant Larson

when our shop guy tested at the battery i believe it was constant idling and reving. volts raised slightly with blower, lights, etc. he seemed to think it all checked out and pointed me towards grounds, fuses, relays, etc. can i check alt volts with my smart charger? i dont have a voltmeter at home. if i connect pos to alt lead and neg to battery neg will it hurt my charger?

mk378

Fuse 15 problem is where the wire harness that goes across the back of the engine rubs on the intake manifold bracket and get frayed and short out. Its repair is extensively documented.

Your car has electrical problems. You need to own a voltmeter.

On the turn signal I would also check that the correct bulb is installed. Swap the bulbs left to right and see if the problem moves. If the lights on the back of the car have lost their ground, the same thing will happen.