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Can I tack on an alternator/regulator question here or should it be in a new posting?
If so I can move this.
I was working on figuring out the alternator/regulator (external) wiring situation on my very first Land Cruiser (a '76 we bought Monday night) and I find continuity between E & E (alt/reg, respectively) but also find continuity between E & F! Any idea why this is happening?
Do you suppose it is related to the three ground wires that are spliced together here? This is just in front of my battery and the single W/B wire goes to the E terminal on the alternator.
There's also a heavier (maybe 14 gauge?) black wire that has a smaller wire tied in with it. I put the loop on the B post (why is there more than one B?) and the clip into N, thinking maybe the PO had wired something up to it. FORTUNATELY it did not catch fire overnight but this afternoon when I was working on the truck my forearm touched the fins on the front of the alternator and it was very warm! Crap! Did I ruin my alternator?
Final question, I think: In the wiring diagram E and F are clearly labeled on the alternator, as is ground, but the "WHT-BLUE" was changed to "WHT-BLK" as you can see in the picture. I downloaded this PDF from somewhere (I forget where). Is "WHT-BLUE" correct on the B terminal as seen in the picture above?
Thanks!
If so I can move this.
I was working on figuring out the alternator/regulator (external) wiring situation on my very first Land Cruiser (a '76 we bought Monday night) and I find continuity between E & E (alt/reg, respectively) but also find continuity between E & F! Any idea why this is happening?
Do you suppose it is related to the three ground wires that are spliced together here? This is just in front of my battery and the single W/B wire goes to the E terminal on the alternator.
There's also a heavier (maybe 14 gauge?) black wire that has a smaller wire tied in with it. I put the loop on the B post (why is there more than one B?) and the clip into N, thinking maybe the PO had wired something up to it. FORTUNATELY it did not catch fire overnight but this afternoon when I was working on the truck my forearm touched the fins on the front of the alternator and it was very warm! Crap! Did I ruin my alternator?
Final question, I think: In the wiring diagram E and F are clearly labeled on the alternator, as is ground, but the "WHT-BLUE" was changed to "WHT-BLK" as you can see in the picture. I downloaded this PDF from somewhere (I forget where). Is "WHT-BLUE" correct on the B terminal as seen in the picture above?
Thanks!
Coolerman
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White/Blue is correct for the B terminal wire color
That splice you show is an OEM ground splice
There should be NO connection to the N terminal on the alternator!!!
White/Green should connect to the F terminal on the alternator and White/Black to the E terminal.
I'm confused as to where that black wire with the smaller wire actually goes back to? Is it something the PO added? You need to track that down before we can tell you where it should go.
There should be continuity between E on the regulator and E on the alternator as they are both ground points.
That splice you show is an OEM ground splice
There should be NO connection to the N terminal on the alternator!!!
White/Green should connect to the F terminal on the alternator and White/Black to the E terminal.
I'm confused as to where that black wire with the smaller wire actually goes back to? Is it something the PO added? You need to track that down before we can tell you where it should go.
There should be continuity between E on the regulator and E on the alternator as they are both ground points.
I traced, and confirmed with continuity test, that the larger black one goes all the way back to the connector for the ignition switch. It attaches to the black/red wire on the ignition switch. (I don't see black/red on the schematic, though.)
On the ignition switch where Black/Red terminates is labeled AM.
Thoughts?
On the ignition switch where Black/Red terminates is labeled AM.
Thoughts?
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The black one on the top right of the screen is the one that was attached to B on the alternator.
Coolerman
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Hmmm... You probably already know this, but your harness has been hacked on, a LOT...
None of the wiring shown in that last pic is OEM. Possibly that harness had a meltdown and the PO made some uh... "repairs"?
That big black wire was originally White/Blue, was 10 ga, and ran pretty much how you have it, key switch AM to alternator B+. The AM means Amp Meter. There SHOULD be a splice in that black wire that also goes to one side of the Amp Meter. The other side of the Amp Meter will have a large White wire. Does your Amp Meter work?
BTW, it is common for Toyota to have different colored wires on devices that plug into the harness. IE when you go across a connector, sometimes the wire colors change.
Now that I know what the large black wire is doing, I can tell you that the PO was tapping power off the large black wire with that little wire attached to it. So unless you need that to power something leave it disconnected.
One last thing, you never stated what your actual problem was?
None of the wiring shown in that last pic is OEM. Possibly that harness had a meltdown and the PO made some uh... "repairs"?
That big black wire was originally White/Blue, was 10 ga, and ran pretty much how you have it, key switch AM to alternator B+. The AM means Amp Meter. There SHOULD be a splice in that black wire that also goes to one side of the Amp Meter. The other side of the Amp Meter will have a large White wire. Does your Amp Meter work?
BTW, it is common for Toyota to have different colored wires on devices that plug into the harness. IE when you go across a connector, sometimes the wire colors change.
Now that I know what the large black wire is doing, I can tell you that the PO was tapping power off the large black wire with that little wire attached to it. So unless you need that to power something leave it disconnected.
One last thing, you never stated what your actual problem was?
The ENTIRE harness was wrapped in black electrical tape, so I *suspected* something was up. Was it originally wrapped in the stuff that looks like electrical tape (but is thicker and stretchy) but only sticks to itself and doesn't leave residue? I have no idea what that stuff is actually called but the avionics shop "gave" me some when I was in the Army.
Okay. So I'll need to trace the white/blue one that IS on B and figure out where it terminates. None of the gauges currently work . . . mostly because they're not hooked up. I'll get back to you on that.
How do I know which B terminal is + and which is -? Are there + & - terminals? The guy I bought it from said there was a positive and negative. He also wasn't the "real" owner. It belonged to his friend who died . . . this is the first car I've ever purchased that came with a title AND a death certificate.
I did notice that on the diagram and initially thought I had blinked and was looking at the wrong line.
Can do!
I think it may have gotten lost in one of the previous posts where I deluged you with questions. The alternator was very warm to the touch with that black wire attached to B and the little flat blade one that comes off of it attached to N. Both since disconnected. I'll remove the little one from that wire altogether today, probably.
One more thing . . . is there supposed to be a ground strap from the alternator bracket or is the bracket being mounted to the engine, which has its own strap okay?
I REALLY appreciate your patience and expertise! Thank you!
I may PM you about buying some proper wrapping for the wires and possibly some wires as I've seen you sell that stuff on your site. Thanks, again . . . you are indeed a cooler man than many.
Coolerman
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Non-Adhesive Harness tape is the proper term for that style tape.
The alternator grounds through the mounting bracket though I recommend that you do use a separate ground strap. If the ground to the alternator is compromised, the electrons will take any path available to them trying to get back to the battery. This usually results in the regulator and ignition grounds being fried.
There is no + and - on the B terminals. You should only use the one at the top of the alternator next to the three pin connector. I really don't know why there are two of the B connectors.
The alternator grounds through the mounting bracket though I recommend that you do use a separate ground strap. If the ground to the alternator is compromised, the electrons will take any path available to them trying to get back to the battery. This usually results in the regulator and ignition grounds being fried.
There is no + and - on the B terminals. You should only use the one at the top of the alternator next to the three pin connector. I really don't know why there are two of the B connectors.
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