Battery not charging issue

[JDMDriver]

I have searched the web and used the search function but cannot seem to find an answer (or another avenue not yet tried) to my problem.

Other threads the OP didn't come back to confirm the solution.
Some threads a solution was found but is confirmed to not be the case for my dads car.

The car
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My dads CB is a stock sedan. No alarm, no aftermarket radio etc. so its should reduce the issues and can be said to not be due to aftermarket parts or modifications.

The Problem
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The battery drains when the car is started and left running (even when revved up to over 1,500 rpm's). It seems the car is just running off the battery until it is depleated (then the whole system switches off - no more electricity to run the computer etc).

I confirmed this by connecting a multi meter on the positive and negative posts while the car is running and see the Voltage dropping with time and went from a bit over 12v to under 11v and continued to drop with the engine running.

For a time the lights (all lights including the headlights) where fluctuating, same with the engine note (possibly due to the fluctuating current) not enough to affect idle reading but i bet it would show if an electronic one such as a multimeter was attached. Till the car died from lack of electricity to power its vitals.

Work done
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It has a new battery (10 months old only) and I have already replaced the alternator with no success.

The battery charges and holds the charge when placed on a battery charger. Overnight the battery keeps charge (even when connected to the car) so no short or unwanted leakage.

The alternator still has plenty of meat in the carbon brushes.

I have checked my grounds or negative connections (battery to fender, battery to transmission, engine to chassy and thermostat housing). All connection are tight and corrosion seems to be at a minimum (no flakes, no powdering, no oil etc)

I read somewhere on the rare occasion the alternator may not be charging due to a loose crank shaft rubber isolator. Tried pulling on the belt to check if it has separated and it seem to be firmly in place.

I thought it may be a plug issue. So I cut the wires and grafted another plug and still the same issue. I was still not satisfied thinking the second plug may be faulty. I then made individual connection to the pins behind the alternator from normal electrical connector pins (so I can see a direct connection) and still the same issue.

Future work
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One avenue I havent tried yet is isolating the alternator from the ELD (Electronic Load Detection) unit. Can someone point me to which wire to remove and the colour code of the wire?

Any one have an alternator plug colour code explanation?

If you have any suggestions please include as much detail so as to avoid confusion (avoid clogging the thread) which may help someone else in the future.

Anyone with similar problems that have found the solution please post your findings.

Not sure if this should be in Beginner technical (perhaps also to get better exposure) but comments and advise are welcome.

Thanks in advance.

[GenDBlade]

Have you tried turning the car on, then unhooking the negative battery cable?

[Binladin]

DON'T unhook the terminal because you could fry your ecu. :/ Make sure the connector in the under hood fuse box is good and clean(it's the only connector with 3 wires coming from it and is the ELD connection).

How to check the ELD straight outta haynes:

1)You need a multimeter! Disconnect the electrical connector from the ELD system and measure voltage between the black/yellow(+) and the black(-) wire (2 outside terminals) with the ignition key on (engine not running). There should be battery voltage(picture shows 12.11 volts). If no voltage is present, check the wiring harness back to both fuse boxes.
2)Measure voltage with the ignition key on (engine not running) between the green/red(+) terminal and the black(-) terminal. There should be 4.5-5 volts (picture shows 4.59 volts). If no voltage is present, check the ELD circuit between the engine and alternator.
3)Reconnect the 3 pin connector to the ELD system. With the ignition key on (engine not running) and the headlights on, measure the voltage on the green/red(+) terminal (middle terminal). There should be approximately be 2 volts.
4)If the tests are not correct, replace the ELD unit. This requires changing the entire main fuse box. The ELD is not available separately. :/

[JDMDriver]

Hi Thanks for the advise.

The ELD you mention should be in the fuse box and lives in the rectangular box to the right of the thick cables going from the alternator and to batter.

However my dads CB doesn't have any for some reason. I checked my CB4 (japanese version) and it is present. So I may need to do some research to find it in the Australian version.

[JDMDriver]

I have re-checked all the fuses in the engine bay and driver kick panel. Pulled them all one by one and not one was in need of replacement. I suspect it is not a short problem but an open circuit problem.

And that open circuit is needed to be closed to complete the charging system.

[JDMDriver]

I did notice that the battery check light on the dash board does not light up when the ignition key is in the "on" position. I believe it should be.

I also noticed that the security light on my dads stereo is no longer blinking when the ignition is in the "off" position.

You may be asking yourself CB's didn't come fitted with security coded radio's. That is because I forgot to mention I did a stereo retro fit (as his original one began to malfunction - not loud and not even speaker outputs anymore). However the replacement is an OEM Honda (S2000) using the factory blue plug pig tail grafted on to the existing wire harness, so I don't think it is an issue. I am confident with my wiring which was working perfectly prior to the electrical issue.

I am leaning towards chasing this anomally first, prior to testing my ELD (once I've found it) or multi meter reading tests on various wires.

My suspicion is there is a break in the system preventing the circuit to work (for the alternator to receive the correct signal and for the battery to then recharge).

[Sordz]

start the car and put the voltage meter on the post on the alternator, if it's still only 12 volts or less and the belt isn't loose then I would say the alternator is dead and replace it. We have auto parts stores here that can test with a load alternators so maybe you can look into that too.

[Fleetw00d]

As Sordz indicated, check the voltage out of the alternator, it should be around 14 volts when the engine is running. You say you checked the grounds (my EX sedan acted as you described with a very poor ground at the transmission), but did you check the resistance through the main ground cable? I had the negative cable on my 90 corrode inside the sheath, so connections were good, but still had trouble charging because of the high resistance.

[toycar]

As Sordz indicated, check the voltage out of the alternator, it should be around 14 volts when the engine is running. You say you checked the grounds (my EX sedan acted as you described with a very poor ground at the transmission), but did you check the resistance through the main ground cable? I had the negative cable on my 90 corrode inside the sheath, so connections were good, but still had trouble charging because of the high resistance.

This is outstanding advice.


Bust out a multi meter and see what kind of condition your cables are in.

Grounds can be tricky since people usually only associate rotten green colors or nasty build up with a bad ground. Dont get me wrong, those are symptoms that are worth attention, but the problem has been present for a long time if that is how you notice it.

If you have shit building up on your battery terminals, you know you have a bad connection somewhere(just another rule of thumb)even if you have no other known issues.

Multi meter will show you a cable is bad long before any visual signs are present.

[JDMDriver]

start the car and put the voltage meter on the post on the alternator, if it's still only 12 volts or less and the belt isn't loose then I would say the alternator is dead and replace it. We have auto parts stores here that can test with a load alternators so maybe you can look into that too.

The reading on the alternator positive post is not the 14 or so volts needed to show a working alternator and a charging battery. I thought it was the alternator also due to this reading and previous experiences.

Thanks Sordz but I have already tried replacing the alternator as mentioned in my first post and it did not solve the situation. This led me to lean towards a higher posibility that it is a connection problem rather than a part problem.

Unfortunately in Australia we dont have auto zones that provide a free electrical check up nor do they provide rental tools, they only sell. Having auto zone service would be really handy when short in cash rather than buying the tool and then coming short in cash for the parts to fix with.

[JDMDriver]

As Sordz indicated, check the voltage out of the alternator, it should be around 14 volts when the engine is running. You say you checked the grounds (my EX sedan acted as you described with a very poor ground at the transmission), but did you check the resistance through the main ground cable? I had the negative cable on my 90 corrode inside the sheath, so connections were good, but still had trouble charging because of the high resistance.

No, I havent checked the resistance thinking it is in reasonable shape but yes that is a good point to check the quality of the flow. I wont be able to do it till the weekend due to work but will do so and give an update.

[Bad_dude]

Did you replace the alternator with a brand new one of refurb? If refurb then it's not unusual for it to be defective even though it looks new.

[djcaz_aom]

I did notice that the battery check light on the dash board does not light up when the ignition key is in the "on" position. I believe it should be.

Okay this is possibly the problem. Remove the cluster and check to see if the bulb is bad. If it is good, check the complete circuit.

If you want check to the complete circuit, do as follows:

- Turn the ignition off.

- Check fuse #2 dash fuse box.
- Bad, Replace. Turn ignition switch on. Does it light up?
- YES. Good to go.
- NO, Go to next step below.

- Now, Disconnect the 4 pin connector at the alternator.

- Turn the ignition switch on.

- Check for voltage on the BLK/YEL wire on the 4 pin connector.

The connector looks like this:



- Is there battery voltage?
- NO, Repair the open in the BLK/YEL wire.*

- YES, ground the WHT/BLU wire on the 4 pin connector.

- Does the light come on now?
- NO, check for a blown bulb. If the bulb is okay, repair the open in the WHT/BLU wire. **
- YES, replace the voltage regulator. It is in the Alternator. Or just replace the alternator.

This is why I always check the bulb first. You end up checking it anyways

* goes to the dash fuse box and fuse #2 15A

** goes to the gauge cluster charging light.

Hope this helps some. Also, FYI, '90 model DXs didn't have ELD.

[Civic slayer]

Mine was doing the same thing but it had a brand new battery not even a week old but on mine it was the alternator that wouldn't charge the battery

[blackack]

To the OP, did you ever find the problem?