Recharging system issue

Hello All,

Anybody ever have any recharging system issues with everything testing good and what was your fix? I'm not mechanically inclined but if I can diagnose a problem I can typically research how to swap out a part. Have not been able to google up this issue and I've talked to a few people that work on their own and they are stumped to find it. I wanted to include as much info as possible so please read through if you can last! (See below)


I have an bare-bones, 134k miles, manual transmission '02 Toyota Tacoma. Use as a primary vehicle without any after market or add ons. A month and a half ago the engine would not turn over. Got a jump, made it a mile and died again. Had some battery terminal corrosion that I cleaned off really well. Same issue so I replaced the alternator with a refurb exact match.

Same issue so I had the battery tested both in and out of the vehicle. Did the same with the alternator. Everything comes back fine/no problems other than a low battery charge (I've been playing the jump every mile game to get to advance auto and Orileys). Next step was to trickle charge the battery based on some online research. Did this over night, gave me a few more issues with breakdowns over the course of a day and then, abruptly, started working. No issues with driving like normal both short and a few far drives for a job prospect (hr and a half away).

Last week she dies again with a dead battery. Trickle charged it again but the battery terminals were very corroded. Cleaned them off and someone said to take it to advance, get dielectric grease and felt washers for the battery terminals as I may be leaking some gas that they should not have corroded that quickly. Never made it as the full battery only lasted about 6 minutes down the road.

Fuses are good, positive and negative battery cables are good, cable on the back of the alternator is good, testing the vehicle while running said there was no trickle leak while the vehicle was off. Anyone I talk to says take it to the shop they are out of ideas.

Sorry for the long read. Any ideas before I have to sink money in at a garage? Thanks for the listen. I have the *most* of the voltage tests numbers and what not if that helps.

 

What voltage and amps is it charging when you had alternator tested?

 

I do not have the print out for the alternator outside the vehicle, everything but.

In the vehicle;

Charging system test

Results: No Problems

No load
13.98V
37.8A

Loaded
13.94V
51.5A

Ripple
37mV

~Edit
This was from advance auto and also has a EXP decision (?) that states the battery was low, a starter test stating cracking normal and a drain test that says "0.03A Pass".

 

37A no load seems high. Were the a/c and lights on when they tested it. You could have an intermittent short in the battery. How old is the battery?

 

Could not find the year on the battery when I had it out. I swapped it out when I bought the vehicle and I *think* that was about 5 years ago. The battery showed fine on the test so I did not replace it.

This is the print out the guy at Advance gave me. During the course of the test he had me turn everything off, lights/ac/radio/high beams, etc. Then he had me turn everything on. I'm assuming the printout would be the second test?

 

No charging warning lamp ever comes on the dash?

 

Low battery light right as it begins to sputter before it dies. If I rev the engine heavy the light will go off and it will hold for another 30 seconds. Edit~ While reved~ Then the light comes back on and it dies.

No other indicator lights though. No codes popped or stored.

 

If all the connections are good on the back of the alternator. I'm leaning towards a battery issue.

 

Just replace the battery.

 

Multi-meter checked the battery at home before it broke down last week.

12.88V (baseline before testing)
12.86 after running idle for 20 minutes.
12.67 vehicle off with everything (lights/radio/etc) on for 10 minutes.

Short on funds. I can borrow from family but there are limits there. Reckon a battery change could fix the issues or is it just because there's not much else I can really try?

 

I'm thinking it has an intermittent short in the battery.

 

Fair enough. Two votes for add a battery. I'll try and find a good price on a battery that has good reviews and google up intermittent shorts in batteries. Thanks for the replies folks, if you can think of anything else- please dont hesitate to share.

 

If you need a cheap battery, just get a walmart ValuePower. They're made by East Penn and since walmart sells lots of batteries, you won't need to worry about buying an old, dusty, half dead battery off the shelf. Those batteries run about $50.

https://www.walmart.com/ip/ValuePower-Lead-Acid-Automotive-Battery-Group-24F/47308797

 

A new battery couldn't hurt because if it's 5 years old it is due to die soon, but based on these numbers I'd say it's likely an alternator problem, although a shorting battery might account for the low voltage at idle.

You should be getting over 13.0 volts at idle and ideally closer to 14 volts. When you rev the engine does the voltage increase?

It's possible the new alternator is bad out of the box.

Another thing to check is the connector on the alternator with 3 wires. Make sure it's snapped all the way in and the wires are intact. You can also unplug it and test the wires. One wire should have battery voltage (testing between terminal and ground) all the time. Another wire only has battery voltage when key is on. The 3rd wire comes from the dash warning light.

 

So this is contrary to the "test" done at the auto parts store? The voltages while the alt is running are indicating it's not working, by your own test. Test it again and see if the numbers are the same. It's possible you have a loose connection, given the intermittent nature

 

The alternator *should* be good. As soon as it was hooked up and giving problems the first step was to see if the refurb was not working right. Tested it in and out of the vehicle. Out of the vehicle no issues (dont remember the exact voltage) but in the vehicle everyone said "Well, its low but not enough it should shut it off". Guy at the store said I could'nt swap it out for another alternator due to the in-house test showing all signs green.

As for the battery I did some looking back at old records and it should be closer to 3 years but that will be my next step. I'm asking around to see if anyone has a matching battery to borrow theirs and see if that fixes the problem. Not holding out on it though to find a battery with the right capacity and size.

Alternator single wire (ground?) and 3 wire connections are fully seated and, as far as I can tell, have no visible damage, looseness, fraying, burns, etc. I followed them up to where the wires end and did not see any apparent damage either. I'll multi-meter the 3 wires and post back, black on metal and red in the pin hole?

Test with the multi-meter on the battery off, idle and full power draw was done by myself. It's on the trickle charger right now. If she stays running I'll get some numbers but I expect it'll die after a few minutes at idle.

 

I'm still thinking loose connection... I would certainly test the pins but the issue could be with the connector itself.

 

Is there a shop in your area that rebuilds alternators, starters, etc.?

They will almost always be cheaper than parts house units in refurbing your OE bits. And their testing procedures should be very thorough as well.

For another battery option, if you know someone who is a Costco member, they have about the best prices on Interstate batteries.

 

The reason I mention the 3 wire connector is that that powers the voltage regulator. Without that power source the alternator will not put out power. And yes, black on metal (or negative battery post) and red on the pin.

Which fuses did you check? Don't forget about the bigger fusible links. There is a big one I think in the circuit between the main alternator cable and wire (somewhere under the hood, probably in the fuse box).

 

Just got back in, trickle charge was at 10amps so like 10 minutes of charging.

Baseline prior to cranking: 12.46
Cranked, in idle, with minimum power draw: 12.97
Cranked, in idle, with full power draw: 11.99
Vehicle turned off with no power draw: 12.56
Vehicle off with full power draw: Started at 11.50s bouncing around but noticeably was decreasing.

This 'test' was all preformed within 3 minutes, nothing was left for 20 minutes or so.

Edit~ Alternator 3 pins multi-meter:

Pin 1: 0
Pin 2: 004
Pin 3: 12.41

Batteries: No rebuild shops but I'll figure it out. Going to be about $100. Have to have a vehicle so I'll have to find a way.

Fuses I checked a bigger one listed 'Alt' under the hood. I'll glance around and see if I can find anything else in the book or printed on the fuse box covers.