bigdaddyclint

As the title says I am fighting a low charge issue. my head is a mess right now lol so sorry if I sound like I'm going on in all directions. So ill start with what happened before all this. car has 216000 miles on it have not had an issue with it in over 2 years none what so ever. so me and the wife are driving home 20 mile trip and the abs light comes on.. I'm like hmm wonder what gives.. drive another 5 miles and then radio kicks off well damn ok battery must be going on me or alternator I'm thinking. get it home after it stalls going around a corner at low speed. had to jump it to get it to the house by the way. which made me think the alternator is doing its job somewhat at least keeping the car running after start.. anyways I get it home and had some cash so I go buy a battery new. check voltage on terminals after install and I'm sitting at 13.5 give or take a half volt. so here I think I'm good to go drive to work no issues headlights off heater on. get out of work its dark. drive home lights on heater on radio on. get within 2 miles of the house and same issues start to happen with abs and radio. this time didn't stall out before I got it to the house. shut it off and try to restart.. dead battery... now I'm like what the hell. I go pull the alternator the next day get it bench tested and its good. Go to another place and have it benched there also and its good. I know those stores are known for **** tests.. anyways I get the alternator back in the car start it up and I'm getting real low voltage at the battery 12.2-13 whenever I use more than just one acc at a time. I checked voltage drop on all charge systems + cables and less than .2 on all cables. also check on the neg side. .2-.3 on the neg side both under load by the way when I checked... all acc were on at the time... I'm at a loss as to what it could be I have a couple other tid bits of info if it will help.. so when the alternator is just running no pos terminal hooked into the charge system I check + terminal on the alternator with a ground to the case and I am getting 20 volts.. as soon as I plug the terminal back into the system to see what the voltage is at the battery I get the same 12-13 volts this is also with all acc off so it should be in therey 13.5-15. also on a side note when I do plug the terminal back into the system I can hear a definite sound difference from the alternator like its being heavily taxed.. unplug it and goes back to nice an quiet. another side note this is also the 4th alternator all reman that has been in this car in over a week all tested fine at parts stores... also 2 new batteries have been tested in the car and every night I'm putting the battery on house charger so I start with a good solid battery in the morning.. I don't know what else to do. I have tried to disconnect the eld (on a side note I also replaced the eld with 4 different ones from a pick and pull yard. and the ecu control wire to the alternator to see if maybe the ecu is messing with the alternator keeping it in low state. but I don't get any change in voltage.. sorry about the long rant and I hope someone can give me some insight into what the hell is going on with this Honda thanks for any help.

Slumpertcivic

Soundly like everything is actually working, just not enough current is getting through the loop to offset the draw.

Just seems like you need to inspect the big wire going from the alternator all the way to the battery and check that path all way back to the load block then to the positive terminal.

Then check the negative connector strap from the battery to the engine.

bigdaddyclint

Hey thanks for the help. I'm not at the car now had to go to work. This morning I replaced the fuse box under hood with a upull fuse box and also I bypassed the white large wire from alternator stud and ran my own large Guage wire from stud to the fuse box under hood also just to make sure I also replaced the alternator to battery wire. If I'm correct the wiring goes from alternator stud to stud on battery and off that there is large Guage wire from battery terminal to starter and also one larger Guage wire from battery stud to fuse box. I replaced all those wires. Still same slow discharge from battery after a while of running accessories battery died. So I redid the grounds again and for ***** and giggles I ran a ground from alternator case to engine block still same damn problem.. what could cause it to drop so damn low. I mean .2 .3 across all connections I guess it could be close to 1 volt drop on all connections added. But I'm pretty sure I checked from + battery terminal to plus alternator terminal and only got .2 .3 across all connections.. I'm lost lol

bigdaddyclint

So I'm sitting here on some forums and reading and it hit me.. maby something other than my standard accessories is pulling major amps when the car is running. Tomorrow morning I'm going to pull fuses and relays one by one in the fuse box under the hood and see if my voltage/amperage shoots up when I pull fuses. Maby it's a stuck relay or some other accessory going haywire. Anyone have any thoughts to this

ezone

You did a lot to the hot cables, but what about the grounds?

Blown fuse #4?

bigdaddyclint

pretty sure its not a blown fuse 4 as I'm getting battery voltage on black yellow at alternator harness. and as far as grounds go I replaced fender wall to motor battery to fender wall motor to frame above radiator and just for ***** and giggles I ran a ground from alternator case to engine. does anyone have the correct voltage readings for the harness like other than battery voltage to exciter on black/yellow I know that one but what else controls the output of the alternator I read somewhere that if you remove green white that the alternator should be put into highoutput mode at 14.5 or around. it just seems like the alternator is not working. I was also thinking isn't 20volts at the alternator terminal high even if there was nothing hooked to the alternator other than harness.. could the ecm be sending a lower than or higher than required voltage to the alternator for the field. or would that just affect the amperage and not the voltage? just shooting ideas around I guess.

NDNV

FWIW, the ABS and then battery lights in the dash lit up when my alternator was on its way out. Also had issues with the alternator bracket not grounding properly too.

ezone

The ELD charging system uses the ELD to monitor current consumption and battery state, and uses that info to run the alternator at a high rate or a low rate depending on electrical use and driving conditions.

High rate is what everyone expects voltage wise (mid 14v area), but low rate can be in the mid-11v to low 12v range, and that's normal.

Open charging voltage may appear screaming high, and I bet if you check with your meter set on AC it may show quite a bit that way too. The car battery acts as a huge capacitor to absorb those high voltage spikes and smooth out the AC ripple.

If the warning lights came on and radio quit, then it's apparent the alternator wasn't charging and voltage probably dropped below a certain level (maybe 10v)

Aftermarket alternators are always a crapshoot. I really hate when a customer wants to cheap out and get one, instead of using one from Honda.

The service manuals have troubleshooting guides to confirm wiring integrity and whatnot.

bigdaddyclint

hey morning and thanks for the info, so I have a little update this morning I was tinkering with the car and made a small discovery.. so I have an extra battery I went ahead and sat it on the ground outside of the car and ran a ground from alternator case to - terminal on spare battery then ran hot from alternator post to + on spare battery started car and low and behold alternator is charging at 14 and some change with old battery running fuse box the battery that's in the car right now is not hooked up to the alternator in any way right now I wanted to just see if the alternator would work without any input from the pcm so I just hooked up the yellow/black to the alternator harness had 12 volts from the battery in the car to excite the alternator. sorry about the rambling I know I'm all over the place. anyways after finding out the alternator is working on the battery outside of the car I proceeded to go ahead and try to figure out if any cables where causing the issue again. I used the known good cables that were making the alternator work for the battery that was sitting outside on the ground charging. it seems like whenever I go and hook the alternator output to the damn fuse box something is kicking the alternator off when I connect it, I then went out and got a used fuse box from a u-pick yard and put that in.. tried it out and still same issue as soon as I plug alternator output into the main fuse box it kicks the motor down just a little and alternator output is gone. its almost like there is a ground somewhere that's kicking the alternator out. I also tried to disconnect the eld just to rule that one out and tried other elds in place of the one that was in there. am I correct in thinking if the alternator sees a ground on the positive output will it kick the alternator off.. I figured it would blow a fuse if that was the case but its not no blown fuses in either under hood box or under dash box. I keep having this weird feeling its the pcm but really don't want to spend upwards of 200 for a test.. any ideas guys.

Calebfox

Did you ever get this fixed cause mine is having the same problem I’ve looked everywhere I’m lost

BrotatoChip

There are replies to the thread you created...

Honda_lover136

Same issue.
2002 Civic.
When car is running, connected to battery, car will only draw from battery. 12v and dropping.
When car is running and I disconnect battery, car draws from alternator and battery cables show 14v.

New alternator, new battery, new ELD.

Challenge persists..

any suggestions?

FRSam

I assume you don’t have an OEM alternator. Civics don’t cooperate with aftermarket electrical components.

Mrwright0411

Did you ever find anything out mine doing same so aggravating

Colin42

Aftermarket alternator?