darkhonda2k2

iTrader: (1)

Ill try to cut the story down to key details, and elaborate as needed.

Last spring, Started right up no problem, drove dog to groomer (~15min drive) Wouldnt start after, push started it, kept alive, but headlights/taillights would kill dash and ICE. Voltage read ~12

I had already replaced the alternator about 6-8 months prior, but knowing those can be junk some times, i tore it out again.

After a busy summer/fall and having more cars than one should, the civic sat there until about a month ago.

Finished installing new (2nd time) alternator, checked all ground connections (big3 kit) and replaced the ELD due to p128 code. Charged battery with tender+

Started right up, ran solid but running voltage only read ~13.8 and would drop to <13.2 with any acc turned on. seems like ELD is never telling alternator to kick into full output mode. charged battery again

few weeks later, now when trying to start, it single clicks, then the dash goes dead 100%. battery voltage still reads good, and now I am running out of ideas.

ezone

If the battery is truly good

Poor connection somewhere on a big cable.

Likely places: Between
Post and clamp
clamp and cable
cable and whatever it's attached to

Could be on positive side or negative.

darkhonda2k2

iTrader: (1)

Yeah I was thinking it must still be connection, there was some corrosion but I thought I cleaned it up pretty well. Guess Ill have to tear it down again.

darkhonda2k2

iTrader: (1)

I hate starting a thread then disappearing.. but work called me away. I bought a new battery yesterday; my optima is 7 years old and had corroded pretty bad so its worth a try is that connection was no longer good. havent been able to install yet but hopefully tonight

I am still concerned when i try to start it i get a single click, then the entire dash goes dead and it wont click again. Any ideas about that? do i need to reset the ecu? (fuse 10?)

darkhonda2k2

iTrader: (1)

EDIT: double post

ezone

Read post #2 again.

If you really want to pinpoint the problem with certainty, I'd suggest to learn 'voltage drop testing' methods.
Losing power/connection from the battery already did this.

darkhonda2k2

iTrader: (1)

Ok, finally got back out there. New battery, New terminals, took off each ground and cleaned them up..

Starts strong, but still runs at 13.7v.
Turned heater on full, tried windows, headlights, all still at 13.4-13.9.
Tried disconnecting ELD, repeated testing. Voltage seemed more stable but still 13.7

What's next to test?

ezone

Sounds OK to me.

Check your meter for accuracy, maybe it's a little off?
Is there a problem with keeping the battery charged or anything?


At 2000 RPM, fully warmed up, no electrical loads:
13.5 volts is acceptable. (If over 15.1v, that's a problem.)

Alternator load test should give over 60 amps at 2000 RPM



HTH

darkhonda2k2

iTrader: (1)

meter is a fluke 87, so accuracy is not an issue.

prior experience says the car at idle would be at 14.5v. Im concerned that the charging system will not keep up with loads at this level due to this difference.
Last time I took it out to test, that 13.5 at idle, quickly became 13.1, then 12.7 before i got it back home (30min driving time)

ezone

Nice!
With the alternator you currently have installed, or a previous unit?

Try yet another alt?

The numbers I tossed out earlier were from the service info, 13.5v was minimum acceptable at the 2000 RPM test.
The ELD system Honda uses is able to raise and lower alternator output corresponding with battery charging and system load demands. It does not always need to keep the alternator charging at high voltage when the system is working right.
Honda has used this method for decades.

CraigW

iTrader: (1)

If you have a meter with a constant connection while running/driving that eld will have the voltage all over the map, up and down.

Since you don't have original alternator.....maybe you don't get the 14+V output.

darkhonda2k2

iTrader: (1)

I used the abnormally warm weather this weekend to tear down the charging system again.

I removed every ground and added a star washer under them to create a positive connection. I added a 4awg ground from alt casing to body connection under fuse box, Added a 4awg positive from alt to battery, Replaced positive battery terminal and removed 5-10mm of positive cable that was looking ripe.

All of this and throughout a 30minute test drive, I now have a solid running 14.0v system. it is not the 14.5 that it was running before, but maybe this alt just isnt putting that out..
it is however a very stable 14v under full load, heater, lights, windows it maintains level. which is a great improvement over the .4-.5v drop i would see in less then 10 min of driving.