Hellow, i have a 1999 honda civic ex auto and i it has almost 200k miles on it and i have never had a problem like this before, excuse my spelling, ok so last night the car started problems starting like for example- when i truned the key it just cranks no start and ALL the dash lights come off but then when i tried again ALL the dash lights stayed on when i truned the key and it started so i drove home, now today i went to start and did the SAME thing but i got it to run so i shut it off to see if it would do it again and this happened, i went to start it again and as i put the key in and turned it no lights came on at all no main realy click norhing at all but the car still cranked but no start so i cleaned both battery terminals and still no lights on dash or main realy clicks, i used my spare working main relay i have in my parts box and still no start no click nothing, i have also a 2000 civic dx so i pulled the main realy from that and put it in the 1999 and still nothing, i have also swappes the mini realy under the main realy by the glove box and still nothing, i have CHECKED every dam fuise in the car and nothing was blown or out of place, im lost right now some help would be awsome thank you (: -ps the blue ecu plug had brown gunk so i cleaned it all and no damage or prongs were missing or any wires out of place and inside the ecu was bone dry this car has never ever had any water damage.

 

You have a key switch electronic pigtail problem... this is a VERY common problem in the '96-00 Civic chassis. Replace it and you should be fine.

 

Could you send a link to the part please or is it this

 

Try rebuilding the ignition switch. Remove the lower cover from the steering column, take the two screws out of the switch, disconnect battery, and carefully pry the white clips back so the white cover comes off. After that, clean the old grease off of the copper contacts, clean the contacts with fine grit sandpaper(300 grit or so), clean contacts with rubbing alcohol, grease contacts with dielectric grease, reassemble, and should work. Better to rebuild the original Japanese parts than to get the cheap Chinese junk.

 

Adding that perhaps you should disconnect the negative battery cable before proceeding to inspect or remove any electrical components like the ignition.

Also, check your fuses for ECM, fuel relay, etc. And grounds. Lastly, ECMs will eventually fail due to the age of capacitors that either dry out or leak & fail completely or more likely go out of spec. Caps are easy to replace if you use a grounding strap to protect the circuit board. & have soldering skills. Some vendors sell cap kits for specific ECMs. Additionally, regarding ECMs, there's a known issue with STA413a IC chip causing intermittent issues w fuel relay & priming. Replacing the chip in their ECM is how a lot of folks reportedly solved similar problems.

 

problem is fixed thank you all for your help it was the pigtail i boight a new one and replaced it and it worked

 

Adding that perhaps you should disconnect the negative battery cable before proceeding to inspect or remove any electrical components like the ignition. Also, check your fuses for ECM, fuel relay, etc. And grounds. Lastly, ECMs will eventually fail due to the age of capacitors that either dry out or leak & fail completely or more likely go out of spec. Caps are easy to replace if you use a grounding strap to protect the circuit board. & have soldering skills. Some vendors sell cap kits for specific ECMs. Additionally, regarding ECMs, there's a known issue with STA413a IC chip causing intermittent issues w fuel relay & priming. Replacing the chip in their ECM is how a lot of folks reportedly solved similar problems.

 

Happy to help.