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[rowsdower]

I have a 96 Hardbody pickup and just yesterday the Brake light and the
Battery light came on. All seems well with the truck though. Any ideas
why this is?

[njmodi]

Time for a new alternator...

Nirav

[JimV]

njmodi wrote:

[Chuck Tribolet]

Why would an alternator problem cause the brake light to come on?

And the Battery light could also be the voltage regulator. Or a loose fan belt. Or a
bad connection at the alternator or voltage regulator.

The Battery light indicates that you running the truck off the battery. SOMETHING
is causing the alternator to not put out enough juice.

If the lights start to look dim, get it home pronto. Carry jumper cables. If
you end up stranded, you might be able to put enough charge on from the other
car to get you home.

Now the brake light: Could be the sensor, could be the wiring. You'll need the
manual to find the sensors. There's probably one that measures pressure differenential
between front and rear circuits, one that tells you the hand brake is on, and maybe some
more, perhaps related to ABS. You can generally disconnect them without causing harm.
I had a truck where you could disconnect all the brake sensors and the light would still
come on in long right-hand corners. I presume the wiring was chafed through somewhere
and grounding to the body, but I'll be durned if I could ever find it. It's not safety issue
because the short to gound is current limited by the light bulb.


Check the voltage at the battery with a
"JimV" <jv9999@yahoo.com> wrote in message news:Jp-dncfeqePAkRveRVn-oA@comcast.com...

[rowsdower]

"Chuck Tribolet" <triblet@garlic.com> wrote in
news:11ocqd2cqpd2if3@corp.supernews.com:

[JimV]

Because of the antilock brakes. The controller has likely detected a
voltage problem. You are right that it could be anything related to the
alternator, but it usually is the alt itself. Or maybe a coincidence,
but again, most likely a failing alternator.

-jim

Chuck Tribolet wrote:

[Jim]

I had a Sentra with the same problem (was the alternator). The reason
they both come on, looking at the wiring diagram (from memory--not going
to dig it out again for this) is a diode miswired into the system.
Diodes are usually used in a bank of lights, where you want one power
source to light up all the lights (like when you first turn your key,
but don't start your engine), but will cause each individual light to
come one separately from an alternate source of power (provided in a
makfunction). I don't know why they stay with that circuit, but they do.

Jim

Chuck Tribolet wrote:

[Chuck Tribolet]

The slippery antifreeze could very easily be causing the belt to slip.
Fix the leak, then hose it all down with fresh water and let it dry.
If that doesn't fix it, try some belt dressing to increase the traction.


"rowsdower" <SOL@noemail.com> wrote in message news:Xns9718D64F23676rowsdower@216.196.97.131...

[gmburns@gmail.com]

It very well may be the alternator, but check the belt tension first. I
had the same lights come on and it was a loose belt.

[Steve T]

Chuck Tribolet wrote:

[Steve T]

Chuck Tribolet wrote: