I am having the same exact problem as we speak, Interior dash lights and outside park lights would flicker heavily until my SRS light came on. What i did so far was take it to Autozone to get the alternator and battery checked but that came out fine. I would however look into any alarm/remote start that is installed on the vehicle..

 

i am having the same issue. just picked up a 2000 Honda civc EX auto for a "reliable" daily. now i am questioning the reliability of this car. my headlights and gauge cluster lights flicker and the car seems way under powered. i am only managing 27 mpgs hwy at most. I am going to check the number 15 fuse and grounds tonight. hope that helps!

 

To me the car is great and it just happens to be a weird thing to go wrong from what I hear 97-2000. Before i check for the wire black/yellow and chase it back to the number 15 fuse i believe. I took it to pepboys and they put it on a tester and the battery and alternator are fine also.
My next step is to check the #15 to the blk/yellow wire coming out of the Alternator. There is NOT 12 volts coming from this wire.

Please if you guys find it faster than me post so we can all fix this issue. " I hate that SRS light coming on/off lately more often than a year ago.

Gas wise there are a few things to do which are easy. but later. Lets fix this issue, not going to let it get to me.

 

okay,
took car to shop and lifted it. Pulled the Alternator plug with the 4 wires coming out of it and tested the blk/yellow strip wire- over 12 volts coming out of it.
I then pulled the O2Sensor bottom one and checked the blk/yellow strip wire-9.50 volts coming out.
I then checked the top O2Sensor and tested the blk/yellow strip wire and there is over 12 volts coming out of it.
I disconnected the neg battery cable and 7.5 fuse under the hood for 6 minutes.
The check engine light was off while driving for maybe 30 minutes. When I started the car after a few hours again the Check Engine light came back on.
The SRS RED LIGHT, stop coming on and the flickering is NOT as strong as before. Maybe the wires were a little oxidized where it plugs into the alternator.
Last week i put the original OEM lenses back on from the after market street lenses and put simulated HID bulbs from Pepboys in and the High Beams blew out, last week when the the flickering was strong and the SRS LIGHT was always coming on. The low beams still work though.
The car seems to idle better and the flickering is very light throughout the car since unplugging and plugging back in the alternator 4 wire plug, unless by chance it could be something else.

What next...

 

9.5 volts on the second sensor is probably a problem. All the black / yellow wires should have about the same voltage since it's a simple parallel circuit. It's better to test under load with everything plugged in and back-probe the connectors.

 

I borrowed a friends volt meter and checked the upper and lower O2Sensors Plugged in with key on , back probing as you said, engine NOT running. They Both READ 12.13 VOLTS!

I then checked the Alternator Plug Blk/Yellow wire and it read around 12.17Volts.

I then unplugged the radio fuse 7.5 under the hood and put it back in after 5 minutes......

I NOTICED that when I turn the head lights on the lights flicker and the engine idle changes slightly!!! When I turn on my fog lights, the same thing happens. So i think we are getting somewhere here.
The CHECK ENGINE light is not back on but I believe when i turn the car back on later to drive it, the Check Engine Light will come on. So why in the heck is the code reading P135 which is upper O2Sensor.

Since I had the car from 2005 to date I put after market headlights on which filled with water on one side, afeter so much trouble with the headlights blowing out do to either water condensation inside and the bulbs not as bright, I went back to original new lenses and put in Simulated HID bulbs. I also added some fog lights with a fuse. Everything else is stock except for replacing radiator, muffler, and a couple of motor mounts. This may or may not be helpful! This flickering started about a year or more ago and just this past couple of months it has gotten worse with the SRS light now popping on and the flickering getting stronger, also blowing out my high beam lights only.

 

It sounds like the problem may be the regulator (inside the alternator) itself. Start car, turn OFF lights, A/C, etc (every electric option), and measure voltage at the battery. Measure on the lead posts that are part of the battery. Should be 13.5 to 15 volts. Outside this range (especially too high) the regulator is not working.

 

Car running, all accessories off! The battery using volt meter was charging at 14.60 VOLTS! I did read somewhere that the regulator in the Alternator sends a false signal to the ECU! Do you recommend changing the Alternator still?

 

Talked to a guy today that mentioned disconnecting the alternator and then start the engine and turn the lights on and see if it flickers, What do you think of that test before I buy a NEW ALTERNATOR?

 

You could try that, just take the belt off which is the second(*) step in replacing the alternator anyway.

(*) The first step is to disconnect the battery. The big wire on the back of the alternator is always live even with the key off.