Jockone

It could be a bad relay for turn signals,I could not figure out why horn fuse affected the seatbelt circuit but it seems to have done it.

Let us know what you find out.

socialistic

iTrader: (2)

I did another parasitic drain test, light was still on bright, pulled the TURN SIGNALS / BACK-UP LIGHTS fuse and it would still cause the light to dim almost all the way. After realizing that the key was turned to the position before "On" the entire time, I turned it off and the test light turned completely off. Whoops.

Anyways, there's no drain that the test light is picking up when the car is actually completely off. I went ahead and pulled all the under-dash fuses and replaced them with the correct rating fuses, and left the blank spots on the diagram empty. I then set my multimeter to the continuity/beep setting and tested all the fuses to make sure they were good.

Tomorrow I'll give the battery a jump and let the car run for a bit and check my idle voltage, load voltage, check voltage output at alternator, check voltage at battery, check voltage at battery after car is shut off. Maybe the results from these tests will help me pinpoint the problem area. I'll also run more ELD tests after all this, since the last time I did it the battery only had about 9volts in 'er.

I have some questions...

-How long should the car run for the battery to fully charge, if the charging system is working properly?

-What should be the range of my idle voltage?

-What should be the range of my load @ idle voltage? For the load I'll just turn on the brights and put the heater on max.

-What should be the range of the battery voltage after the car is shut off?

-What should be the range of voltage from the alternator output post while the car is running?

-How many volts at the least are needed to start the car?

socialistic

iTrader: (2)

Still need answers to my post above.

Also, I may have found the cause of the problem...



That is the harness from the cab, those are the three plugs that connect it to the engine harness. As you can see, almost every wire was cut and re-connected/taped back together for some reason. I'm wondering if one of the connections is bad?

They also did this to the two harness plugs on the driver side, but I already fixed those...these current three I don't think I can easily fix because some of the wires were cut RIGHT at the damn plugs. I may have to find someone parting one of these cars out, and have them cut off that cab harness for me so I have enough wire to work with.

Jockone

Can you depin the plugs and repair the wires then repin plugs?

socialistic

iTrader: (2)

Possibly, but not sure how these pins are for these plugs or if I have a de-pin tool that would work(I have a lot of PC gear, I build custom gaming rigs). The downside to this idea is that I would be hunched over that motor for a long *** time depinning all those wires, and I'm recovering from a back injury I received several weeks ago...so that may get a little painful.

Jockone

Ok but you will be bent over repairing the wires anyway won't you?

I don't think I have an Si harness and the wiring will be diferent on a Dx but I will check on the Si later.

socialistic

iTrader: (2)

If I repair the wires I can actually sit in a chair while doing it. To de-pin I'd have to be standing to get closer to the plugs, since I'd have to see the "triggers" of the pins in order to unlock them and pull them out. :\

CALI CHRI

Not trying to thread jack, but JOCKONE I have had the same problem, my battery dies everytime I let it sit for more than a day, when I connect the positive my driverside and pass side doors click. So if I just disconnect the seatbelts will it stop this problem?

socialistic

iTrader: (2)

I have all the wires repaired. While doing this I realized two things, not sure if they matter or not...

-I'm using a PM6 ECU out of a 90 EX. It's the correct ECU code I need for my '90 Civic Si, but could there actually be a difference since it's from a different car?

-I'm using a main relay out of a 90 LS, and it does have a different part number than the one that came in my car. I have the one that came in the car, just didn't get around to reflowing the solder on it until today. Is there a difference between the two?

I can't move the car out of the shop and jump the battery until I can replace the front/passenger brake hose, until then the car is on jackstands and the other voltage/eld tests have to wait.

Do the parasitic draw test to find out what's draining your battery, it's easy.

-Make sure car and all accessories are completely off, key shouldn't be in the ignition at all
-Disconnect ground cable from battery.
-Connect the clamp/cable of a test light to the ground cable.
-Connect the probe of the test light to the ground post of the battery.
-If the light is on, that means something is putting drain on your battery. If no light, you're good to go and don't need to continue the test.
-While the light is still connected(may need a second set of hands to hold it for you), start pulling and replacing fuses one at a time...start with the engine bay fuses, then the dash fuses. Eventually you'll find one that makes the light go out...that circuit is what was draining your battery with the car off.

Jockone

I don't know for sure but that is what was causing the problem on my car,do the draw test and see what happens first whith the belts connected and then with them disconnected if light goes out then that could well be your problem.

Just as information I hoseclamp the probe side of the test light to the battery and use the clamp end on the cable to the battery.

Jockone

I don't think the ECU or the main relay are the problem at least pretty sure about the ECU if you get a chance it won't hurt to repair the main relay and swap it out just to make sure but I don't think thats it.
Damn I hate electrical problems.

socialistic

iTrader: (2)

Well, I'm fairly certain the main relay has nothing to do with the ELD/charging system but as you said it wouldn't hurt to use the one that came with the car.

As for the ECU...it is my understanding that the ELD sends a signal to the ECU when a drop in voltage/increase in load is detected, and it is the ECU that cranks up the output of the alternator.

If the ELD is passing tests and not causing a CEL, and the alternator is passing tests...then that leaves either the wiring or the ECU. Maybe the '90 EX didn't have an ELD?

Jockone

Don't know for sure if it did or not but I think most civic/crx's did.

When you tested it didn't it give you a test for voltage and wouldn't that come from the ECU?

socialistic

iTrader: (2)

There's three wires for the ELD, one is which is a ground. The test has you check the other two wires...one should display battery volts, the other should display 5v and then 2v when the headlights are turned on. All test results were within spec.

As for those tests having anything to do with the ECU, I'm not sure. I don't know what wire(s) run from the ELD/alternator to the ECU. I'll have to track down an ECU pinout diagram to find out.

Jockone

I think the 5v-2v wire is to the ecu but not sure let me know if you don't find a pinout diagram and I will check my manual and get back to you.

socialistic

iTrader: (2)

According to this diagram...



There's two alternator wires...blue and white/yellow, and one ELD wire...red/green. I'm not sure what kind of tests to run on those wires, though.

From what I can recall...the three wires running to the ELD are white/yellow, red/green, and black.

Also, notice the name of the diagram...could it be that the SI PM6 ECU differs from the non-SI PM6 ECUs? I'll check the alternator/ELD wires at the ECU and see if the ECU even has those pins.

Jockone

the wires for the ELD are as follows

Black----ground
Black and yellow------positive 12 volt supply.
Green and red------will be a positive from pin B19 on the ECU

I am using a manual for an 88 Honda CRX because it has the best wiring diagrams I have found and it has worked for everything I have done on 88--91 civics and CRXs.
Let me know how you get on or if you need any more info.

CALI CHRI

Thanks alot JOCKONE and socialistic, I'll run that test asap! Sorry again not trying to thread jack.

Jockone

Good luck.

socialistic

iTrader: (2)

I plan to run those tests on the ELD again with a full battery, even though I don't think that'll change the results apart from what the black/yellow lead will show in volts. I'm also going to test voltage at the battery and at the alternator output with the car on to see if there's a difference, there shouldn't be if everything is working properly.

Beyond that, I don't know of any other tests to run. If the alternator is good, the ELD is passing tests and not throwing a CEL...then I don't know what else it could be apart from the ECU.

Jockone

Yeah I don't know either but I dont know how it would be the ECU if it is telling the ELD what is going on ie the voltages from the test are right on the green and red wire.

Being stuck on dial-up sucks so save me searching and going to links does the test have you doing voltage tests with the headlight switch in position 1 being 2.5--3.5 volts between green and red and a ground and then dropping to 1.5--2.5v with headlights in position 2?

socialistic

iTrader: (2)

It had me test for 5v with the headlights off, and then test for 2v with the headlights on. I'm talking about low-beams, not highs or parking lights.

Jockone

The manual is not very clear about whether it means low/high beam or if it means parking lights and then headlights.

What it says is:
under conditions in chart to right measure voltage between B19 pos and A18 neg,

headlight switch,first position (small dot) 2.5---3.5 volts
headlight switch second position(big dot) 1.5---2.5 volts


is voltage listed available _____>no =faulty load detector


yes = substitute a known good ecu if symptoms go away replace original ecu



I know thats probably what you have done but wasn't sure.

socialistic

iTrader: (2)

I think that means parking lights and low-beams, because the "second position" voltage reading is the same as the test I was using that told me to turn the low-beams on.

Since all my results were good, that left me thinking my ECU may be at fault...and your test does say to try a known good ECU. Maybe that's what I need to do? I'm still trying to figure out if an EX PM6 is any different than the SI PM6, specifically in regards to that ELD circuit...because that may very well be what's causing my problem.

andyz

Adjustable electromagnet coils take the place of permenent magnets in an alternator. The magnetic field in the adjustable coil is increased or decreased depending on how much current you want of the alternator. This adjustable coil then interacts with the non-adjustable 'generating' coil to produce the output current. In this way you can get a consistent output across different engine RPMs.

The ECU must adjust the current to the adjustable coil to increase/decrease the overall output based on the signal from the ELD. If your ELD, ECU or alternator are not matched properly......

I'd get a potentiometer and connect it from the ELD signal wire to ground. Start at 1Mohm or 100 KOhm and keep tabs on the voltage. Start reducing the resistance and see if your alternator kicks into high gear. Usually you can hear the change in belt load in the engine 'tone'.

If this works maybe you can keep it that way to properly match these different components.