socialistic

iTrader: (2)

Still having problems and I can't figure out what's causing them...

-With car running, voltage drops to around 11.5v when a bunch of stuff is turned on(heater, brights, rad fan mainly) but doesn't go back up like it normally should. It's like something is failing to tell the alternator to work a little harder to make up for all that crap being turned on. If I turn it all off and blip the throttle, the voltage jumps back up to about 13.6-13.8v. It never goes over 14v like all my past hondas.

-Car won't start sometimes...when this occurs, nothing happens when I turn the key. Lights don't dim and I hear no clicks or anything. I did replace the entire key cylinder kit, including the ignition cylinder...but I inspected it and it was way better condition than the old one. Double-checked the connections for it and the starter, everything looks good.

-After a week of working on the car, starting it and letting it run for an hour or so at a time, I let the car sit in the garage for just a few days and the battery died...but I can't seem to find any signs of drain on the electrical when the car is off.

Here's what I've done so far...

-Been through three brand new alternators...so it's not the alternator.
-Been through two new-ish batteries, and both were tested in a second vehicle...so it's not the battery.
-Installed two brand-new heavier gauge ground cables from battery to trans and battery to chassis...so it's not the grounds.
-Installed brand new battery terminals...so it's not the terminals.
-Checked all the fuses at least 20 times...so it's not the fuses.
-Checked and cleaned ground from valve cover to core support.
-Checked and cleaned ground from engine harness to thermostat housing.
-Checked every little bit of wiring under the hood
-Deleted the a/c harness under the hood because there's no a/c, and the wiring was a mess
-No CELs at all.
-Car stays running after battery is removed.

Headlights, brights, signals, hazards, heater, sunroof, horn, EVERYTHING on this car works great. There just seems to be a problem with the voltage not going back up when stuff is turned on, and the car sometimes doesn't start.

What else could it be? Does this car have an ELD in the fuseblock under the hood or not? Does it sound like the ignition or the starter may be going bad? If so, could that cause the other issues?

CivicSD

sounds like alt to me.


i know u replaced it three times. what brand are you using. (who is rebuilding it)

socialistic

iTrader: (2)

They were all from autozone. They were all tested before purchase, and tested again upon returning them. Two were normal units, the third was a mitsubishi unit...pretty much the same thing, visually different, came with a brochure explaining why it looks different and that it is guaranteed oem-replacement for my car.

All gave the same results, and the mitsu one is the currently-installed alternator. Autozone will not let me exchange them anymore(unless actually broken) since there wasn't even anything wrong with the first two.

I also agree that this *sounds* like an alternator problem, specifically a voltage regulator problem, but by this point that's virtually impossible considering all the alts I went through and all the tests ran on them.

Edit: Is the ECU what controls the voltage regulator in the alternator? If so, maybe the ECU is bad or a wire between the alternator and the ECU is bad? It'd have to be such a small issue, that it ONLY affects the voltage regulator...kind of a long-shot guess, but anything's possible I suppose.

RyanA

Kind of sounds like grounds still. I'll think about the problem on my way to IL today and PM you back on 417.

Ryan

socialistic

iTrader: (2)

Here's how I currently have my grounds set up...

There's two 2ish gauge cables with gold-plated connectors running from the ground terminal...one deadends at the chassis ground spot under the battery tray, the other deadends at the clutch-cable bracket on the trans.

I found a clean OEM VC-to-core support ground cable, and installed that where it needed to go.

The thermostat ground contact area was cleaned/sanded because it was previously causing the car to not start and fuel pump to not turn on, it seems to be fine now.

I did clean/sand all ground contact areas except the one on the trans bracket, it didn't look like it needed a sanding so I left it as-is...I could give that one a sanding and see if that helps.

You can hit me up on 417 or shoot me a text if you come up with anything, I'll have my cell on me all day.

RyanA

Give me a call in an hour or so and we'll brain storm. I have to head to work to grab a truck then head to my shop to grab my trailer. Heading to Wentzville first then to IL so I'll be on the road for the next 13 hours or so.

socialistic

iTrader: (2)

No prob, I'll shoot you a call sometime between 600-630.

Jockone

If the battery died after a few days in the garage it sounds like you have a drain on the battery somewhere,have you tried to check for a power constant power draw?

socialistic

iTrader: (2)

I have been trying to figure out for the last hour if this car has an ELD, because nothing in the fuse box looks like the 92+ ELD photos I see on google. I called Honda to ask them, they weren't even sure, they said "We think it did come with an ELD, and you can't order a new one, must order the whole fuse block."

After some more searching I came across an old thread on here someone started, something about electrical problems on their CRX. Then I seen a post in that thread that contained a picture...

https://honda-tech.com/forums/showpo...64&postcount=8

That guy says that is the ELD, if that's the case...then I have that too. I have my fuse block taken apart on my desk and that plug leads to a small black box. Is this for-sure the ELD for my car? If so, this being faulty would definitely explain the voltage issue I'm having because this is what is supposed to tell the alternator to kick out more power to normalize the voltage level when stuff starts getting turned on.

It wasn't exactly dead, it had about 11.8v and wouldn't start, turning the key didn't even dim the headlights. I guess this would be expected since I am having voltage issues and all. I have yet to find anything putting drain on the electrical system with the car off.

Jockone

So back to your first post "I did replace the entire key cylinder kit, including the ignition cylinder" I take it you mean the ignition switch on the bottom of the lock cylinder?
Turning the key and not getting anything happen at all sounds like it could be a problem in the ignition switch.

Pretty sure you do have or should have a ELD on that car but don't have a manual here to confirm right now.

socialistic

iTrader: (2)

I mean the whole keyed ignition assembly that pretty much clamps to the steering column, that's what I was sent by the dude on ebay selling a "complete key cylinder kit", so that's what I replaced. Once I can figure out why my voltage isn't normalizing when stuff is turned on, I'll move on to the starting issue rather than trying to tackle everything at once.

I didn't think pre-92 civics had an ELD, and my chilton's only defines what it is, but Honda somewhat confirmed that my car does have one and that post I linked shows what I have in my fusebox and he says that's the ELD...so I guess I have it. My ELD has to be bad, given the problem I'm having with the voltage.

Found this post which may serve useful...

https://honda-tech.com/forums/showpo...61&postcount=6

I'll run out and do that test right now, and report the results.

Edit: Ok, so I passed all the tests...battery is only holding at about 9volts since the car hasn't ran in almost a month, but I don't believe the voltage is important as long as there's a number for me to work with.

Test #1 - With ignition turned to "On" and ELD plug disconnected, test for battery voltage between ELD plug black/yellow and ELD plug black. Battery reads 9 volts, power between those two wires reads 9 volts.

Test #2 - With ignition turned to "On" and ELD plug disconnected, test for 4.5-5.0 volts between ELD plug green/red wire and chassis ground. It's reading at 4.0-4.5.

Test #3 - With ignition turned to "On" and ELD plug connected, test for approximately 2 volts between ELD plug green/red wire and chassis ground. It's reading at 2.0-2.5 volts.

According to those results, my ELD is good...unless I did the test wrong or that test isn't meant for my specific year/model. If my ELD is not bad, then I'm out of ideas.

Jockone

Had a very similar problem on a 91 DX turned out to be seatbelt sensor in the drivers door.
Does your car have the door seatbelts?

socialistic

iTrader: (2)

What were the symptoms of your problem?

My car does have the door seatbelts, and I recently installed a new passenger door because the one on the car was replaced at some point and was from a pillar-belt car. If it matters...my seatbelt lights between the visors and the one on the cluster do not light up at all. Also, this car has DA seats with their plugs cut, I'm not sure if there's plugs under the seats, haven't checked yet.

Jockone

Symptoms were power drain but very slow,car not charging properly but good alternator leading to no start after 3 4 days of sitting without driving.

Might be a long shot but if you have a test light remove pos terminal on battery and attach one end of test light to the terminal and the other to the bat lead,if light is on there is power draw.Then start to pull fuses one at a time when light goes out you have found the problem circuit.
IIRC when I did this it was the horn circuit fuse under the hood that put the light out but when I put the fuse back ib I could hear clicking at the drivers door so I got the wife to come and help after I took of the door panel and it was the seatbelts that were making the noise but only as she was installing or removing the fuse.I unplugged the seatbelt plugs and the problem went away after about three weeks of no problems I installed a new belt on that side and it has been fine scince then.
Not saying that is for sure what your problem is but who knows.

socialistic

iTrader: (2)

So if I read that correctly...with the car off, I remove the positive cable and connect a test light between that disconnected positive cable and the positive post on the battery?

andyz

check this from AdvanceAutoParts for a 90 Civic Si alternator

Worldwide Alternator
Part No. 14825 Warranty
Reman; 60 Amps; INSTALLATION ALERT! This application uses an "Electronic Load Detector" in conjunction with the Electronic Control Unit to regulate alternator output. Follow prescribed test procedure for a "no charge" condition.; See Tech Tip # 626; Test Chart Page # HF


Try to measure the ELD sensor signal voltage while the car is running.

If you are into hacking it, it seems the ELD is only to improve gas mileage by reducing alternator belt load and subsequent idle speed so you could add a pull-up resistor of sufficient value to +12 to simulate an ELD signal. Your alternator would be on high alert 24/7.

andyz

A little tricky, but something like this.

https://honda-tech.com/forums/acura-integra-6/electrical-load-detector-eld-bypass-2873474/

Jockone

Yes install test light as you said if it lights up something is drawing power.

socialistic

iTrader: (2)

I disconnected the ground cable from the battery, then connected the test light between that and the ground post on the battery. It lit up fairly bright...pulled one fuse at a time until I found the one that made the light go really dim. According to the diagram, it's the TURN SIGNALS/BACK-UP LIGHTS fuse...wtf?

While in that fusebox I noticed it's completely full of fuses, but the diagram shows like 3 or 4 blanks. Didn't notice any fuses at all for seatbelts, so I unplugged the seatbelt units one at a time and the light didn't dim at all.

I also noticed that almost every single fuse is the wrong rating for what should be there...I noticed the same thing with the under-hood fusebox a few months ago and replaced them with the correct rating fuses.

Here's what my fuse diagrams look like...

https://honda-tech.com/forums/showpo...51&postcount=2

I suppose I'll go ahead and remove the fuses in the blank spots, and replace the rest with the proper rating fuses. Not sure what to do about my turn signal/reverse light circuit throwing drain on the battery with the car off...

andyz

Ok, leave that fuse out and start testing the battery voltage again.

socialistic

iTrader: (2)

Gotta jump the car since the battery is only at 9 volts, will do that here in a few since it is on jackstands in the shop. Probably should buy a battery jump box or charger for crap like this...

Oh, might be worth mentioning that all my turn signals/reverse lights/hazards work fine...but sometimes, very rarely, I'll hear a buzzing sound when I hit the left turn signal and it won't work. I just turn it off and back on and it's fine. Maybe a bad relay is causing that, and is also putting drain on the battery?

andyz

If you think that's it, start removing bulbs and wiring harness looking for damaged insultation, places where water occasionally infiltrates, etc.

Somehow I still think it's the ELD, even with heavy load due to a damaged insulation short, if you alternator and ELD are working your car will charge and voltage will be 12-13 or 14. I think..anyway.

andyz

Another tip: people always make a big deal of spreading that di-electric grease all over the spark plug boots. Seems to be that's a bit useless. Those boots are so long and those caps over the valve cover are almost air-tight.

But if I was messing with the electrical, I'd spread that grease all over the bottom and side and everywhere on bulbs/harness connectors.

tonythetuner®

Your ELD is located in you fuse box under the hood only way to replace it is with replacing the whole underhood fuse box. Cuz it is. Incorparated into the fuse box its self

socialistic

iTrader: (2)

Yeah, came to that conclusion earlier. Ran the ELD tests linked above and passed them all.