2.7Taco

New truck, new to the forum! I went from a Ford diesel to this BEAST of a little Tacoma! I must say I love it!

Now, my current issue, day or nigh, idle or driving, warm or cold, low Rom is high rpm, randomly my battery light will come on or flicker sometimes just a quick flicker sometimes for up to a minute. When it does this the blower fan speeds up and the headlights get brighter. When the light goes off everything returns to normal. It will also when trying to start just click sometimes, click, click, little crank, click, fire up...and other times fires right up.

I've had the truck for a week and only done basics...oil, plugs, wires, cap, rotor, erg vacuum leak, cleaned throttle body and mass air flow.

Battery sticker says 3/14 and is a Wal-Mart battery.

To me it seems like a poor conection somewhere, or alternator. But I've got NO clue!

Ideas? Where to start?

wyoming9

iTrader: (1)

For some reason your charging system is over charging most likely the Voltage regulator

If the lights get brighter and the blower motor speeds up

Time for a alternator rebuild if it is the original Denso

Time to break out the Meter and do some checks

Seems you might have some electrical work to do.

Check all the grounds

How many miles ??

Maybe time for new contacts in the starter solenoid as well

Nothing like getting a new to you Vehicle up to speed

TheDurk

From your description, it sounds to me like you have a poor connection on the sense wire to the alternator. This causes the alt to think the battery is discharging, the light comes on and it puts out max voltage causing the blower speed and lighting effects. I just helped to trace exactly this on the 4Runner board.

The sense wire is one of the three small wires in the plug on the alt. They can break right in the plug, or along the run to the fuse box. You could also have a failing ALT-S fuse, assuming Tacos have this fuse like the 4Runners do. Unlikely, but I'd change this fuse anyway to rule that out.

I'm sorry, I only have wiring diagrams for 4Runners, or I'd tell you exactly which wire it is. But start by looking carefully at that three wire plug and looking for any damage at the plug, and along those wires as far as you can follow them. Push and pull the wires with the engine running and a voltmeter on the battery. If the voltage jumps, you know you are on the right track. Healthy system should stay in the range of 13.5-14.5 volts. If it goes over, it's a bad sense wire or a bad voltage regulator. An intermittent fail is more likely to be the wire.

As Wy9 said, starter clicking issue is probably unrelated and most likely the starter contacts.