Hello.
I have a 97 Civic LX non V-TEC and the speedometer doesnt work and the lights pulsate after ignition.

Ive had the car about 3 months and the pulsating lights has always occured. BUT!!! Because of the winter weather over here in L.A CA, its gotten severely worse. The car sometimes doesnt turn on and Im forced to get a jump start about every 3 days. After the jump, the car runs fine and the pulsating lights is minimal. But as the temperature drops, the pulsations gets worse and faster. ALL MY LIGHTS, IN AND OUT, ARE AFFECTED, INCLUDING THOSE ON THE DASH. ALSO, the speedometer aint work and sometimes JUMPS to the 80 or 90 mark.

Ive had both the battery and the altenator inspected and checked and both are fine.

People on here really seem to know a whole lot on Honda's!
I like my civic and i aint want to lose her!

 

It's a common problem with your model year. The wires behind the engine get frayed and short out on the intake manifold bracket. Then the alternator does not power up properly. Fuse #15 under the dash will usually blow. Thus this is known as the "fuse 15 problem".

 

Thanks, Ive been doing research around the site and several people have the same problem. I'm going to check the fuse #15. I just dont know which it is. The case covering the fuses has the names, but no numbers. It simply gives the name and the amps.

Do you know which wires specifically get frayed?

THX, been a whole lot of help

 

X2 on that, I have the same problem with the pulsating lights, and also have an extremely low idle when headlights are not on. I turn them on and can hear the alternator kick in and the idle goes back to normal for the most part. new battery and less than 1 y/o alternator, and new "big 3" grounding and terminals.

anyone know of a thread that shows pics or diagrams of the frayed wires and tells how to fix? also, will a blown fuse throw a CEL?

 

I don't have a pic but if you were to get under the car and look up, follow the small harness leaving the alternator that goes across the back of the engine toward the main harness near the thermostat. The problem spot is apparently at the bracket that braces the intake manifold to the engine block.

Tape up and/or splice the wires (if completely worn thru) and install a new fuse.

The situation typically does cause a CEL with codes for the speed sensor and / or the oxygen sensors, and maybe the purge valve. All those parts are actually OK but they lose their power when the fuse blows.

 

WOW
Problem solved!
The #15 fuse was blown!
thx a lot!
The wires arent frayed because my Civic has another crashed Civic's engine.
I Talked to the mechanix who installed the engine and sold me that car and they said they have cahnged the alternator twice and couldnt find the problem! haha, cant beleive it was a fuse!!

 

I had this very "fuse 15" problem back in 2007 on my 1998 Civic LX; guess what, same problem in Feb. 2010; back in 2007, the pulsating lights, strange acting speedo, etc. threw CEL codes related to both O2 sensors, etc. (0135, 0141, 1298, 0501); i thought i fixed the wiring harness that rubbed through on the intake manifold bracket by wrapping it in electrical tape a few times; but over the past two years, it rubbed through again. So this time, I wrapped the wires in electrical tape and then I encased the wires is a plastic cover, like that covering many of the other wires in the engine, and then secured it to the bracket so it won't rub; hopefully, this fix will last longer than two years. Then, I replaced the 7.5 fuse at location 15 in the fusebox under the steering wheel. By the way, the fuse box is numbered, rather faintly, so that you can see which fuse is number 15. If you have any of the above codes or symptoms, don't just replace the fuse because it will likely blow again if you don't correct the root problem, being the wiring harness on the intake manifold bracket rubbing through.

 

For more information, read this TSB.

 

I have 1998 Civic exhibiting the exact problems and codes of the "Fuse 15" problem except the fuse is not blown. Is this possible?

Thanks,

Pat