ALTERNATOR (22RE) mistery problem (?)
 

Truck is a 94 manual 4WD xtra cab 22RE.


We're facing recurring alternator failures. Have read already numerous threads on this, but we are somewhat lost. This is the status:


- Two failures in the last month, 3rd failure yesterday.
- First 2 failures have been the voltage regulator.
- First failure happened at a slow traffic jam at a highway, slow idle speed, stereo was on, low headlights on. Replaced the internal regulator (non OEM) and brushes (OEM Toyota). Replacement regulator failed 2 days later, after forgetting the ACC switch on for 20 minutes.
- Replaced with a better non-OEM brand regulator, and a new battery. Worked without flaw during our + 1000 km trip from central to northeastern Mexico last week, carrying heavy load (+650 kg).
- Yesterday, while driving around town we made frequent parking stops, keeping the truck on, idling for 10-15 minutes at a time before retaking our driving. Stereo off, headlights off (was daytime). Suddenly, the brake and battery dash indicator lights turned on. Battery charge indicator was at 3/4. Drove immediately to a safe parking spot before having to face a drained battery. Haven't turned the truck on again.


So I'm suspecting the regulator might have failed again. We do have a new replacement regulator, as we anticipated we might face a new failure, but I don't want to use it until I'm sure what the reason these regulators are failing is, as it might be something else than simply these replacement regulators being crappy as non-OEM parts. If it fails us again, we will be in deep sh** as now we are in a rural town deep in the Sierra Madre Oriental mountains in Mexico, and up here the scarce spare parts stores only carry old Ford and GM parts, but practically no Nissan or Toyota.


Last time we replaced the regulator, we checked beforehand fuses and wiring. No accessible wiring we could observe in the engine bay was exposed or torn. We changed the 80 AMP alternator fuse (was ok, but we changed it anyway), wiring was ok. We also very recently changed all three belts, and right upper and lower cooling hoses. Regarding fuses (both underhood and in the driver's side panel), no blown fuses, but THIS we found in the fuse box:



https://cimg2.ibsrv.net/gimg/www.yot...1c1b2e1020.png

https://cimg9.ibsrv.net/gimg/www.yot...e0eab54833.png


https://cimg5.ibsrv.net/gimg/www.yot...5916c3dd73.png


The melted fuse is NOT BLOWN, still works (checked with a current tester). It is the EFI fuse.


TWO OTHER SUSPICIOUS SYMPTOMS which make us think there might be a short somewhere which might be causing the recurring failures:


- High headlights work ONLY when pulling the left lever (temporary mode), but shut off when pushing the lever (permanent mode).

- YESTERDAY, at a certain point during a 2 hour drive offroad (way before the idling parking during the town drive), we noticed white smoke seeming to come out from the alternator. Now, I must indicate that this alternator, when we bought the truck roughly one year ago, was abundantly drenched on some kind of oil (motor oil I think) from a leak somewhere which currently has disappeared. Don't know if this might be the problem, but I must point out that even in this condition, the alternator worked for almost a year without issue.


Finally: we have no starting issues. Sometimes it takes a bit longer and I must press the gas pedal to get it going, but that happens rarely.





SO WE'LL APPRECIATE ANY HELP OR FEEDBACK GIVEN!

Any coolant dripping on it from that u-pipe right above the alternator? That what is was for me. Is the rear bearing "ok"? It should be rusty. https://www.yotatech.com/forums/f116...elated-306130/



I have gotten alternators from "those shops" that: didn't work at all, only worked a bit (kaputt diodes), two that basically had an internal short (high whine, obviously full "load" - will smoke)
If it doesn't fit: https://www.yotatech.com/forums/f120...nt-fit-260698/

The headlight problem "should" be a separate issue: a lot of power goes through the actual switch at the steering wheel and the contacts corrode. Use very light sandpaper between the contacts.


I do love the wood block battery hold down spacer. I ran that exact piece of wood until I got fed up and go a "Japan" sized battery.

What is the condition of your battery? A bad battery can make your alternator work harder to keep it charged. If it's the same battery that has been through multiple regulator boards, maybe it's time to change it. Clean and inspect all your battery\alternator cables and connections, and also make sure your grounds are good and shiny metal on metal.

Assuming you have no fluid leaking on to the alternator, leaks don't stop by magic in my experience.

And the rectifier isn't damaged allowing AC current into the system, which tends to kill the regulator.

I would blame the melted fuse block. Once plastics melt they tend to form carbon which is reluctantly a conductor of current.

What value fuse is the melted one and is that value correct for the circuit? I’m suspicious that some other patched up ckt is giving the alternator problems.
Power steering fluid can drip from the pump to the alternator and that’s how mine went out.

You sure it is the EIF and not the IGN fuse?
EFI fuse does not affect charging directly; only indirectly - if EFI fuse is blown engine would not run and it would not charge - LOL!
However, any corrosion/burning/pitting on connections is bad.

Here's schematic for 1994 4Runner 22RE Charging System. Charge fuse does not enable charging. "Engine" fuse does.
https://lh3.googleusercontent.com/g2...=w1112-h663-no

I suggest you take voltage readings at "IG", "S", "B" and"L" as Cory85 suggests above. Voltage readings of normal charging system should be same as on my 1986 22RE's listed on my thread: "How Charging System Works". Let us know what you find different.

THANKS EVERYONE for your useful and quick replies. I'm sorry for my late response, but I just got hold of a wifi signal.



No coolant dripping at all, I changed the upper coolant hose before replacing the regulator. As for the bearing, I'll take a look to see if it's rusty.




Battery is new. Changed it along with the last regulator replacement.

As for the battery cables, I started with the (+) cables. THIS I found after cutting the sheathing on the one that goes to the fuse box:


https://cimg1.ibsrv.net/gimg/www.yot...a5ade3b011.png


https://cimg8.ibsrv.net/gimg/www.yot...cf2536316e.png


AS you can see, there is some kind of gummy fill beneath the sheath, covering entirely the wire. IS THIS SOME KIND OF FUSIBLE CABLE? CAN I SAFELY REPLACE IT WITH NON-FUSIBLE CABLE?


As for the other + cable, I renewed the crimp connection, but there is what seems to be some kind of fusible integrated into the cable:


https://cimg1.ibsrv.net/gimg/www.yot...f349a3fce9.png


I sincerely have NO idea if this fusible (in case I'm not confusing it with something else) is supposed to be there. DOES SOMEONE KNOW if I can discard it when replacing the cable?




As for finding other possible issues in the wiring system:

- There are two connectors in the engine bay I have absolutely no idea what purpose they serve. They sit at the uppermost left side (passenger side), behing the fuse box towards the firewall.


https://cimg0.ibsrv.net/gimg/www.yot...4c1dad8487.png


Finally, there is a cable hanging loose near the starter. It sticks out from the "package" that goes towards and over the transmission body. Again, does anyone know what purpose this cable has / if it should be connected to something somewhere? Couldn't find it in the FSM.



https://cimg9.ibsrv.net/gimg/www.yot...32fcd701f4.png





I'm not sure I understand this



I'm inclined too on that. Can the fuse box be repaired, or will I likely require to replace the whole fuse box?




Value is 15 AMP. It is labeled as the EFI fuse.





LAST BUT NOT LEAST: the "ENGINE" fuse in the fuse panel (or kickpanel) inside the cabin, driver's side, has NO continuity when tested, either with the engine shut of or running. The fuse is not blown, and even when replacing it for a new one, there is no continuity. ALL OTHER fuses in that panel show continuity. IS this normal?


I appreciate very much your help. As I said before, we're in a remote location in the sierras in Mexico, and the few automotive electricians down here have experience with old Ford and GM trucks, but not at all with Toyotas, so I would try to at least accumulate as much knowledge on the electrical / wiring system and potential issues beforehand if I must irrevocably take my truck to one of them.



THANKS AGAIN!

Awesome location! What toyota's are made for...

Gummy stuff is probably deteriorated insulation. I would inspect/clean/fix/replace that whole wire. Quicker than time spent guessing.

Stock circuit should have the following connected to battery. :
POS:
Very Thick wire to stud terminal of starter solenoid.
Thick wire to fusible link wire to fuse block. Popular method for replacement is measure gage of main wire, crimp on fusible link wire that is 4 gages thinner than main wire. Use parallel crimp, not butt-connector.

Negative:
Very thick wire to engine block
Thick wire to fender ground

That loose red wire is a mystery. Best thing is to physically trace it.
Those two connectors... could be for Backup light / 4WD switches that were disabled, if they're long enough to reach the starter near transmission?
Re: EFI fuse, best to take voltage readings.

https://lh3.googleusercontent.com/ft...w=w802-h712-no

https://lh3.googleusercontent.com/gS...=w1024-h682-no
PARALLEL CRIMP MCGYVERED - Because I could not find crimp connector other than wasteful bulk-packaged.

The fuseholder you circled in yellow in the photo is the kind commonly used with car stereos. Somebody must have smoked the fusible link and repkaced it with that.

Is that the oil pressure sensor that is not hooked up?

Agree, it is a fused cable like those used to supply a high-power audio amplifier. The inner positive cable you should be able to trace into the cabin somewhere. I can see it routes under the distribution block and continues along the inner fender towards to firewall. Trace it out if it isn't connected to a working amo that you are using it should be removed or atleast disconnected and secured out of the way.

The factory oil pressure sender wire comes from the efi loom, it has a disconnect above it and comes out much closer to the middle of the intake.

It also appears to be red, indicating a power supply wire, and needs physically and electrical traced to determine its function and status.

...
RAD's advice for replacing the entire short section of the primary power supply wire to the distribution block is a very good idea. Once a fusible link starts to fail it is never going to be the same.

...
The rectifier circuit on an alternator is made up of the diodes.

Given your latest posts I suspect the loose hanging wire is intermittently shorting out which is causing the fusible link to begin to fail (the gooey stuff you find in the batter cable to the distribution block), and is some how attached to that melted fuse slot. The burnt (carbonized) plastic is carrying the current (not the fuse) and producing heat which in turn melted the fuse body.

All right. I just ordered an OEM Toyota remanufactered alternator from a dealership at the closest city from our location (4-hour drive; fortunately they will have it available in a couple days). Last time we drove the truck, smoke definitely was billowing from the alternator, accompanied by a distinct burning smell. Local electrician checked the alternator and says the stator is smoked. Charging is currently fluctuating between 1/2 and 3/4 capacity.

I'm pretty sure the alternator isn't the main issue, but rather a symptom or a consequence of some short occurring somewhere. However, it is plain clear that our current alternator isn't the OEM one, and it is pretty beaten up, and with at least 3 regulator replacements done by us. So this is a good time to replace it with an OEM one.

I also ordered the "Wire, Fusible link repair" (part # 82991-35020) to replace that gummed up cable along with the alternator. As Co_94_Pu suggests, ther is probably a problem within that cable, linked to the melted fuse slot. We'll replace both alternator and fusible link and report results.


As for the grounds, all seem in good shape, except for the one up above and near the alternator, the one that bolts behind the power steering pump, as it is quite drenched in oily gunk. It's quite a PITA to clean it up without removing the entire power steering pump, which I'm trying to avoid.





Truck has an Alpine stereo with two Pioneer speakers. I doubt it has any amplifier installed, but I suspect those speakers must draw quite a bit of power. So is it better to leave that fused cable as is? I only renewed its crimp connection to the battery terminal..




Actually, the oil pressure (or is it volume?) gauge in the dashboard isn't working (was that way since I bought the truck). Since I monitor regularly motor oil level, I didn't pay much attention to it.


If I'm not mistaken, that red loose hanging wire has a male spade connector. I still haven't been successfull finding its connection point.




THANKS for all your useful replies! I'll be reporting back soon!

You can cover the loose wire with some heat shrink tube, this will prevent it from shorting to anything u till you have time to follow and find its other end and what it is connected to.

The "extra" positive cable should be identified ASAP. Disconnect it. Check your stereo still works, any "off-road" lights still work, CB/shortwave radio still works. ... You don't have a wench do you, it could.be for one of those. "Back in the day" Alpine stereos commonly used an external amplifier.

That ground is a very important one, it's the ground for the sparkplugs and the alternator. Suggest you attack it with a baby bottle brush and a can or two of brake cleaner while you have the alternator out for replacement. It shouldn't be covered in oil and gunk, this puts us back to the question of how sure are you there isn't a coolant, power steering or oil leak killing your alternators.

All right, so last week I finally got a chance to travel to the Toyota dealer at the nearest city 5 hours from our location to pick up both the new (remanufactured) Toyota alternator and the new fusible link wire.

https://cimg2.ibsrv.net/gimg/www.yot...ccb2147a9d.jpg

https://cimg5.ibsrv.net/gimg/www.yot...f602b66a52.jpg

https://cimg9.ibsrv.net/gimg/www.yot...72bbf37ac2.jpg

New fusible link wire is at the left in the photos above. Definitely the one I'm replacing was NOT an OEM one, as its metal plate wasn't made from brass and its crimp connector was pretty flimsy compared to the new one's.


But RAD4Runner, does what you suggest then:

"Thick wire to fusible link wire to fuse block. Popular method for replacement is measure gage of main wire, crimp on fusible link wire that is 4 gages thinner than main wire. Use parallel crimp, not butt-connector."

mean I must NOT connect the crimp connector end to the POS terminal directly?


This is the way I just set it up:

https://cimg3.ibsrv.net/gimg/www.yot...81be87dce9.jpg


On the other hand: I have not yet turned on the engine to check functionality of the new alternator/fusible link wire/wire insulation repairs done, because I want to first deal with the leak I mentioned that had gunked up the previous alternator with oily substance.

Even though it had seemed to diminish or almost disappear, there was a drop or two of oil over the old alternator when I took it out (you were right, Co_94_PU). So I'm pretty sure either the power steering pump or its return hose (or both) must be leaking (strangely, however, level at the reservoir is the correct one and the red ATF fluid seems pretty light and not oily to me, not what the two drops of heavy, shiny and yellowish oil on the alternator were like).

Both ends of the return hose are damp, so I'd like to at least replace that:

https://cimg9.ibsrv.net/gimg/www.yot...f4087c0bdd.jpg


QUESTION IS: will this force me to have to bleed the steering system? Does anyone know if the return hose can be replaced without the risk of air entering the system?



Thanks for your help, everyone!

There is an o-ring on the nipple for the feed line(larger hose) to the ps pump. The nipple is held to the pump with one bolt. This o-ring is a common source of leak.

RAD4Runner's suggestion applies to making your own fusible link wire. Since you have a Toyota one, you just hook up one end to the battery and the other (metal plate end) to the fuse box.

:safari:

You will want to cycle the steering from steering stop to steering stop regardless, this is the bleed/purging procedure. There is a substantial amount of fluid in that line which means when you put it back on empty a substantial amount of air in it, it is going to try to make a big mess.

Looks good, O.P.
Like Old87yota says. Just make sure you have enough slack so there'll be no tension in case battery shifts.
On mine, the stock FL wire does not run under the battery hold downs.
Return hose is the low-pressure one that's just clamped, right! I replaced mine, drained and cleaned the reservoir. I just bought 13 inch power steering hose from NAPA.
Rather uneventful. Details on my build thread.

https://cimg5.ibsrv.net/gimg/www.yot...3f28c8aeed.jpg
Greetings from Yosemite!
Drove the Corrolla because roads are paved all the way, and if there's snow, I think FWD with cables would be smoother to drive than 4WD.

My fusible link does not go under the battery hold down either, just a relatively straight shot from the battery terminal clamp to the fuse box.

Not to derail this thread, but RAD4Runner, what year Corolla do you have?

:safari:

The missus' 2016, Jake. :)

OK back on topic...