RPM drops & electricals turn off (split secs) when A/C compressor engages

**jeDi13** · June 9th, 2014 07:42 PM

Hi fellow Tsikoteers.

Please help me with my Civic ES A/T. I started to notice that the car has been having hard starting problem recently. It's not that often though. To quantify the frequency, maybe once a week, and no particular time of the day. But what I noticed is that after a drive (short or long distance) and then I turned off the engine, I won't be able to start the car the next time I will turn it on (for about 5-15 mins since shut down). There's a little crank at first, and then it fades away as I try it further until there's no cranking at all. But I have to reiterate that this doesn't happen always, all the time, and frequently.

But what bothers me is that starting yesterday, the RPM drops to 200-400, radio turns off, ABS and SRS dashboard lights turn on and off, A/C fan turns off (all happens in a split second), when the A/C compressor engages. The engine doesn't die nor vibrates. It's as if there's a less than a second loss of current. I fear that it will die while in use (still doesn't happen though) if I won't be able to solve the problem soon.

I've read that it could be the idle up actuator, servo, throttle body, IACV, or the A/C compressor. But please take note that this doesn't happen all the time, every time so I'm having doubts the problem could be those. How about the battery? Is there any chance it would be the culprit?

Thanks in advance.

**jick.cejoco** · June 9th, 2014 08:10 PM

Originally Posted by jeDi13

Hi fellow Tsikoteers.

Please help me with my Civic ES A/T. I started to notice that the car has been having hard starting problem recently. It's not that often though. To quantify the frequency, maybe once a week, and no particular time of the day. But what I noticed is that after a drive (short or long distance) and then I turned off the engine, I won't be able to start the car the next time I will turn it on (for about 5-15 mins since shut down). There's a little crank at first, and then it fades away as I try it further until there's no cranking at all. But I have to reiterate that this doesn't happen always, all the time, and frequently.

But what bothers me is that starting yesterday, the RPM drops to 200-400, radio turns off, ABS and SRS dashboard lights turn on and off, A/C fan turns off (all happens in a split second), when the A/C compressor engages. The engine doesn't die nor vibrates. It's as if there's a less than a second loss of current. I fear that it will die while in use (still doesn't happen though) if I won't be able to solve the problem soon.

I've read that it could be the idle up actuator, servo, throttle body, IACV, or the A/C compressor. But please take note that this doesn't happen all the time, every time so I'm having doubts the problem could be those. How about the battery? Is there any chance it would be the culprit?

Thanks in advance.

try to see what the ignition switch is doing by temporarily install a light where you can observe it. the light should be on when the ignition switch is in the run mode. tap the bulb feed wire to circuit 15. if the switch was bad and has an intermittent loose connection, just like what you stated in your symptoms, the light will turn off with the temporary loss of power to circuit 15

**jeDi13** · June 9th, 2014 08:38 PM

thanks jick. but I have little to no knowledge when it comes to auto electrical. so when you say "circuit 15", where exactly are you referring to? and what tools should I need in order to perform those steps?

**jeDi13** · June 9th, 2014 10:49 PM

yung iba, any idea mga sir?

**ParticleX** · June 9th, 2014 11:28 PM

How old is your battery na? Check if there are white deposits on the terminals. Go to a battery shop and have it load tested, bigyan mo na lang ng pang-yosi.

Hirap pa naman sa ating mga A/T cars ang mamatayan ng battery. Kung pwede lang ilagay sa 2 at itulak...

**jeDi13** · June 9th, 2014 11:38 PM

more than 2 years na rin. pero nung 1st year is hindi naman daily drive. wala namang deposits sa terminals. sige ipa-check ko na rin, tutal out of warranty na. hirap lang kasi na sabihin ng mekaniko na palitan ganitong part, bili nalang ng bago kaya nagtanong muna ako rito. thanks ParticleX sa reply.

**glenn manikis** · June 10th, 2014 06:20 AM

Originally Posted by jeDi13

yung iba, any idea mga sir?

alternator ang problema mo sir... nakakabit din ang rpm sa alternator... if there are times your rpm is dropping it means your alternator is giving out below normal amperes... probably palitin na carbon brush mo... kaya it does not happen naman all the time kasi meron pang natitira sa carbon brush mo...

ask ko lang sir.. nabaha ka ba?

**jick.cejoco** · June 10th, 2014 06:55 AM

Circuit 15 is HOT IN RUN or the same feed as the PCM and the ignition coil. Hondas are know for bad ignition switch. Try this first

Nakiki wi-fi lang

**jeDi13** · June 10th, 2014 04:56 PM

Originally Posted by glenn manikis

alternator ang problema mo sir... nakakabit din ang rpm sa alternator... if there are times your rpm is dropping it means your alternator is giving out below normal amperes... probably palitin na carbon brush mo... kaya it does not happen naman all the time kasi meron pang natitira sa carbon brush mo...

ask ko lang sir.. nabaha ka ba?

oks sige sir glenn, ipapa-check ko na rin yung alternator. pero hindi naman nabaha (at least during my ownership). 2nd hand ko lang kasi nabili 2 years ago na. pero ngayon lang siya naging ganyan. kakapunta ko lang sa Honda SPA for valve cover gasket replacement. iniisip ko rin may loose connections na tinamaan sa pagkalas/pagkabit ng valve cover. thanks!

Originally Posted by jick.cejoco

Circuit 15 is HOT IN RUN or the same feed as the PCM and the ignition coil. Hondas are know for bad ignition switch. Try this first

Nakiki wi-fi lang

okay, this has been noted sir jick. i'll take note of this and mention to the mechanic. thanks!

**non-vtec** · June 11th, 2014 04:45 AM

Regarding the cranking issue, experienced that in old civic. Problem was poor grounding. It could also be the cause on your power loss sa electrical. Suggest you tighten and clean the battery's negative and positive cable and other body grounds using sand paper/wire brush. Try those first because it won't cost you a centavo.