Hey everyone,

I've noticed that at times certain lights dim when others are in use. For instance, I have a parking brake light that's always on due to the switch striker being gone. When I use the turn signals, that parking brake light dims as the signal blinks. Also, if the headlights are one the dome light dims when the truck is off. Is this because of a weak alternator not fully charging the battery, is my battery dying, or is this just normal for old 4Runners? The truck is also having some trouble starting lately as the mornings have been a bit colder. That could be a whole host of things though I'm guessing(starter, spark plug wires, distributor, spark plugs, etc.) Any insight is appreciated. Thanks for reading.

-JFW-

 

About normal I'd say... Run over to Auto Store and have them to check your battery and alternator. It's free ya know

 

I'd be looking at batteries.... Everything draws power from the battery, the alternator keeps battery charged. Check alternator voltage output, verify clean, solid connections, etc...

But my '84 did the same thing for a while. Then I got an Optima yellow top. No more dimming on my truck. I can leave radio on at the site all day long, and she will start right up when it's time to roll.

 

Toyota-boy - good point, thanks! Lol

Rokblok - OK, good to know I'm not the only one. Wouldn't happen to know the part number of that yellow top offhand would ya? if not, I'll find it.

 

It's normal. The old runners used 55-60 amp alternators I believe. At night with the lights on (headlight dash and rear), the heater and the radio its barely breaking even.

Simply changing the brake parking and turn to LEDs will help immensely.

Also is a worthy upgrade to replace the puny charge wire from the alt to the batt with some thick 2 gauge.

 

I believe I put a Group 34 in mine. Available at most auto parts stores. Spendy, but mine has been a great battery.

 

Ok, thanks. I'll check that out. Yeah, everyone I've known that's used Optima batteries has said you pay but you get what you pay for.

 

don't get an optima, the quality apparently went downhill several years ago, lots of complaints on multiple forums, something about production being moved to mexico.

https://www.google.com/search?newwin...k+poor+quality

odyssey is a good option, or get one of the agm batteries from sears, i think that they are made by odyssey these days(?)... under $200 if you get 'em on sale.

 

I saw all these reviews before I bought the yellow top. And I was skeptical... But I dove in and haven't had an ounce of trouble. Fuel pump quit down the street from my house yesterday, so I decided to try and blow up the starter by cranking it back home. Made it about 120yds into the driveway and fired right up after I replaced the pump. My yellow top has no lower quality issues...

 

Well after talking to a local 4x4 shop guy it may be the starter. I don't know...I'm going to go to NAPA sometime this week and have the battery, alternator, and starter tested. Check all the connections.

osv-

I looked into those Odyssey batteries. The aforementioned 4x4 shop guy spoke very highly of them as well. Said he sells a lot of Optimas, but the Odyssey is a better battery. Both are freakin' pricey, so we'll see. Do you know which size I would go with on the Odyssey? Their site lists pc1200lmjt under 2.4 liters, etc. then lists a 25-pc1400T under 2.4 liters, optional.

 

Oh, nevermind. Just a difference in amperage between the two.

 

First, it would help if you mentioned Truck specifics.

Neither lights or starting symptoms are normal, but they can be expected of old battery and/or poor connections from corrosion/neglect.

Symptoms point to weak battery. If you've had your battery for 3 or more years, it can be expected.

IF your lights are dim when engine (alternator) off but are OK when engine is on (alternator producing power), then it's most likely a weak battery, AND that your alternator is doing it's job.

Check battery voltage with headlights on AND engine OFF. What do you get?
Now check batt voltage with headlights on AND engine ON. Voltage should range approx between 13.5 and 14.5V.

Yes, all those check make sense. However, the starter is not the cause for dim lights.

As for "starting" do you mean trouble "cranking" the engine, or getting combustion going?

I have posts on my build thread on understanding and troubleshooting "Cranking" issues.

 

Oh, ok. So you're saying I could have two separate problems? lol great. I'll check that stuff when I get my multimeter back from my friend.

Umm...I guess getting combustion going. I turn the key and the starter cranks and cranks and cranks. I do this in about 3-5 "spurts" and on the second to last it almost starts, then starts the final time. So yeah, I guess it would be trouble getting combustion going. Thank you for breaking it down like that.

 

It could be anything but, IF it only happens when engine is cold, one easy thing to check is your cold start injector and cold start timing switch system. FSM describes how it's done (resistance check at different temps). However, mine turned out to be just improperly plugged in connector.

 

buy the sears glass mat battery, it's cheaper than anywhere else, and it's the same battery.

 

Yeah, thanks, OSV. I'm also considering the DieHard Gold advanced AGM. Good specs, better CCA than stock, reasonably-priced, and MADE IN THE USA!

 

RAD4runner-
Yeah, probably the cold start injector. I called Jerry at 22REperformance.com for something else, mentioned the cranking issue, and that's exactly what he said. I'm going to test it this weekend to make sure.

I googled DieHard Gold Advanced AGM battery and the first thing that came up was an article from ConsumerReports.org. They DID NOT have good things to say about that battery. That's just one site though, so who knows. If I go high end I'll just spring for an Odyssey. Curiously, they're cheaper on the Odyssey site than on Amazon.

 

Good to know.

I ordered the Diehard Advanced AGM for store pick up but as I left work, my battery with post lose and separating from housing/container, was making my alternator work erratically and truck died, so I just got one from AAA. Only 525 CCA Oh well. Maybe it will work on my Corolla so I can I switch later.

 

wrong battery.

think DieHard Platinum, not gold... I don't know anything about the gold battery.

it's on sale for $196 through tomorrow, I think.