DTN

when my tib is charging the battery, after a start, voltage reaches up to 14.6. When operating normally, voltage sits at 13.5 or so. When i turn the car off, voltage drops to 12.8, then creaps down as i use the battery. At 11.4V the car will not start.

there is nothing that should be causing that problem with the left/right. It dosn't make sence. Is your alternator tight? It may be that your "new" alternator is teh suxor. I'm checking webtech.

make sure when the car is on with engine off, the battery light comes on, or it could be the 20 A fuse.

majik

I've lived on webtech, but there may be something I'm not finding. Fuses looked fine

I think the old alternator was fine, the new one should be fine as well.

before the swap, I would stay steady at 14.2 - 14.4 all the time, with the occasional drop to 13.8. Rarely under that. Now I can't even get up to that. I feel like my car needs some Erectile Disfunction pills to get it up

DTN

Ok, basically the charging system works like this... you've got a alternator with a voltage regulator, a battery and a 20A fuse that we're concerned with

Power comes off the alternator and goes into the voltage regulator on the alternator. Power goes to the battery, and through a 20A fuse back to the voltage regulator to be sensed by the voltage regulator which adjusts the output power. I've got the schematics. I'll try to verify that will cause all the symptoms that you have, but the problem is in the fuse, alternator, wiring, or voltage regulator.

this mother f***er is hard as hell to read. I see a relay coil in the voltage regulator circuit, but it does not tell me where the relay contacts are, or it's too messed up to read

Btw.. check the blue fusable link B

Dweet

Dumb but necessary question, where are you reading this voltage from anyway?

majik

I have a Dakota Digital voltmeter connected to the ignition wire for the head unit. It has a digital readout with .1 incriments. I've had it for a few years so I trust it. I haven't moved it or messed with the conenction in any way, so there should be no issue with that. Valid question, should have stated the source since I've been quoting voltage so much.

Now that I think of it.... I may have moved the connection last year when rewiring my subs. It may be directly connected to the battery now. I'm about 85% sure that it is, but again, I haven't messed with the connection any time recently.

DTN

DO you have a standard multimeter? You really need volts and ohms to troubleshoot correctly.

Dweet

You need to be reading the voltage directly off of the battery terminal before any load is put on it. If something is drawing current it may drop the voltage a little. One of my amps had a voltmeter on it and it was wired directly to the battery, so I always went by that in my Tib.

majik

I'm really not good with electronics. Volts and Ohms really mean nothing to me, except for knowing what a battery should be putting out at different times. Unless you can tell me exactly how to use the multimeter, I can't provide you with any info on volts/ohms. 02.gif I do have a multimeter, just can't use it

If I had a voltmeter on the battery AND another one on the ignition wire @ head unit, would they ever show a different reading (if there was nothing wrong with the HU wiring specifically)?

DTN... your diagram means nothing to me sad.gif

I'm concerned that the problem lies within the ECU wire tap. The auto-manual conversion requires tapping one of the pins to a constant 12V power source. I thought the friend who wired that in mistakingly put it to the wrong power source (one that isn't constant 12V) so I re-wired it directly to the battery. That is the rewiring I mentioned above.

Dweet - I'll verify the source of the voltmeter when I get home from work tonight. I'm pretty certain it's on the battery

Dweet

Volts = Voltage, Ohms = Resistance usually you do an Ohms test for continuity
Im not really getting why you are having varying voltages unless your alternator is flaky which could have it test as good sometimes.
There is a single wire going straight from the alternator to the battery to charge it. The car itself runs off of the alternator once the car is started.
Now if the alternator is not wired into the car properly from the harness being messed up somewhere in the circuit then that would cause your car to run off of the battery and thus cause battery problems. You should probably get someone who is good with electronics and can read schematics to get this fixed.

DTN

MT: you need to check to make sure the red line and the yellow line are good. Use a multimeter and find the corresponding wires. the red line is the big one from the alternator. the yellow is a smaller one that comes from the fuse box back to the alternator. You need to check the items along the red and the yellow lines.

The things that run along the red and yellow lines are: power connection from the alternator, a big wire that goes into the engine fuse box, a blue 100A fusable link, the connection to the battery, the battery itself, grounding to the battery, a light blue 20A fusable link, a smaller wire that runs from the engine fuse box back to the alternator, and a connection at the alternator.

Ground from the alternator is provided by the physical connection to the engine block, so check grounding from the engine to the chassis as well.

The red and yellow lines I drew do not relate to wire colors, i used them to display the different lines. I just filled in the wires to make it easier to read. The schematic is a graphical representation of the actual physical components. the big box at the bottom is the generator, the box on the left is the battery, and the top right is the fuse box.

Your problem is between the fuse box, the battery and the alterator, as well as associated wiring.



If I were you, i'd pull the 2 fusable links and check the connections with your multimeter set to ohms and see if it reads between 0-1 ohm of resistance. To make sure the multimeter is set correctly, touch the two leads together to see if it reads 0 ohms. This is the Ohm symbol, or close to it, the Ohm symbol does not have an apostrphy ( ' ):
<span style="font-size:36pt;line-height:100%">�

</span><span style="font-size:10pt;line-height:100%">After checking the fusable link, I would check the wires from the fusable links back to the connection on the alternator with the multimeter set to ohms. It's possible they were pulled from their place under the fuse box.

After that, I would check to ensure the presence of engine, battery, and alternator grounding.

Really, that's all it could be... that or the alternator.</span>