Alternator or Battery Problem ???

So I went to AutoZone and they checked my battery and alternator with
a mchine that attaches to the battery terminals and they told me both
were fine. Well I'm not sure if I believe them...

Here's what happens with my car:

* sometimes fails to start, but the dash lights come up.
* when idling sometimes the power to AC, radio, and transmition gets
cut off.
* when starting from a stop sign, same as above, and car jerks a bit.
* the remote key doesn't always work, and when it does, the "beep"
when locked is more like a "mooooo".
* basically it seams like there's not enough juice, but it doesn't
happen ALL the time.

Here's the kicker: it all goes away when the AC is off.

So what can it be? I checked the fuses and connectors around the
battery. All look fine.

> wrote in message
...
> So I went to AutoZone and they checked my battery and alternator with
> a mchine that attaches to the battery terminals and they told me both
> were fine. Well I'm not sure if I believe them...
>
> Here's what happens with my car:
>
> * sometimes fails to start, but the dash lights come up.
> * when idling sometimes the power to AC, radio, and transmition gets
> cut off.
> * when starting from a stop sign, same as above, and car jerks a bit.
> * the remote key doesn't always work, and when it does, the "beep"
> when locked is more like a "mooooo".
> * basically it seams like there's not enough juice, but it doesn't
> happen ALL the time.
>
> Here's the kicker: it all goes away when the AC is off.
>
> So what can it be? I checked the fuses and connectors around the
> battery. All look fine.
First, at no cost except your labor, remove, clean, and reconnect
cables. They can look fine--even be so tight you cannot remove them w/out a
wrench, and yet not make good electrical contact.
Then, check further if you find there exists a problem. HTH, s

On Thu, 7 Aug 2008 11:59:03 -0700 (PDT), wrote:

>So I went to AutoZone and they checked my battery and alternator with
>a mchine that attaches to the battery terminals and they told me both
>were fine. Well I'm not sure if I believe them...
>
>Here's what happens with my car:
>
>* sometimes fails to start, but the dash lights come up.
>* when idling sometimes the power to AC, radio, and transmition gets
>cut off.
>* when starting from a stop sign, same as above, and car jerks a bit.
>* the remote key doesn't always work, and when it does, the "beep"
>when locked is more like a "mooooo".
>* basically it seams like there's not enough juice, but it doesn't
>happen ALL the time.
>
>Here's the kicker: it all goes away when the AC is off.
>
>So what can it be? I checked the fuses and connectors around the
>battery. All look fine.

Sounds like a short somewhere. When I got my car the doors would lock
and unlock by themselves at erratic intervals. Turned out to be a bad
car alarm wiring job. Loose connection.
If nobody has reworked your factory wiring, could be a bad harness.
You have to isolate the circuits causing problems and go from there.
Start by making sure everything visible has a tight clean connection.

--Vic

> wrote: Alternator or Battery Problem ???

Here's what happens with my car:

___ sometimes fails to start, but the dash lights come up.
___ when idling sometimes the power to AC, radio, and trans cuts off.
___ when starting from a stop sign, same as above, and car jerks a bit.
___ the remote key doesn't always work, and when it does, the "beep"
when locked is more like a "mooooo".
___ basically, it sems like there's not enough juice, but it doesn't
happen ALL the time.
___ the kicker: it all goes away when the AC is off.

AutoZone checked my battery and alternator with a machine that
attaches to the battery terminals and they told me both were fine.
So what can it be? I checked the fuses and connectors around
the battery. All look fine.
__________________________________________________ ______

It does sound like a bad connection somewhere.

You can't tell the quality of the connections by looking
at them. You have to disconnect every connector,
inspect and clean it, then reconnect it. This includes:

Pos Cable to Pos Battery Post
Pos Cable to Start Relay Terminal
Pos Cable to Fusible Links.
Pos Cable to Alternator Terminal.

Neg Cable to Neg Battery Post
Neg Cable to Engine Block
Engine Block to Chassis Cable

Try these, then post again noting the results and
identifying the vehicle. You may get more help.

Good luck.

Rodan.

On Aug 7, 6:19*pm, "Rodan" > wrote:
> > wrote: Alternator or Battery Problem ???
>
> Here's what happens with my car:
>
> ___ sometimes fails to start, but the dash lights come up.
> ___ when idling sometimes the power to AC, radio, and trans cuts off.
> ___ when starting from a stop sign, same as above, and car jerks a bit.
> ___ the remote key doesn't always work, and when it does, the "beep"
> when locked is more like a "mooooo".
> ___ basically, it sems like there's not enough juice, but it doesn't
> happen ALL the time.
> ___ the kicker: it all goes away when the AC is off.
>
> AutoZone checked my battery and alternator with a machine that
> attaches to the battery terminals and they told me both were fine.
> So what can it be? * *I checked the fuses and connectors around
> the battery. All look fine.
> __________________________________________________ ______
>
> It does sound like a bad connection somewhere.
>
> You can't tell the quality of the connections by looking
> at them. * You have to disconnect every connector,
> inspect and clean it, then reconnect it. *This includes:
>
> Pos Cable to Pos Battery Post
> Pos Cable to Start Relay Terminal
> Pos Cable to Fusible Links.
> Pos Cable to Alternator Terminal.
>
> Neg Cable to Neg Battery Post
> Neg Cable to Engine Block
> Engine Block to Chassis Cable
>
> Try these, then post again noting the results and
> identifying the vehicle. * You may get more help.
>
> Good luck.
>
> Rodan.

OK, so I disconnected the battery and cleaned the connections with a
wire brush.
Still having problems.

Now, I started the car with AC off, and disconnected the battery
negative terminal. It started to chocke a bit, but still ran. Then,
with neg. disconnected, I turn the AC on, and it died. So I
reconnected the neg, turn the AC on, and started the car. Then i
disconnected the neg. and it died instantly. I repeateed this 4 times
with the same result.

I'm guessing alternator. You?

> Now, I started the car with AC off, and disconnected the battery
> negative terminal. It started to chocke a bit, but still ran. Then,
> with neg. disconnected, I turn the AC on, and it died. So I
> reconnected the neg, turn the AC on, and started the car. Then i
> disconnected the neg. and it died instantly. I repeateed this 4 times
> with the same result.


Sounds to me that you are too stupid to do your own car electrical
work. I have to say this about anyone who would remove the negative
battery cable with the car running.

wrote:
> On Aug 7, 6:19 pm, "Rodan" > wrote:
>> > wrote: Alternator or Battery Problem ???
>>
>> Here's what happens with my car:
>>
>> ___ sometimes fails to start, but the dash lights come up.
>> ___ when idling sometimes the power to AC, radio, and trans cuts off.
>> ___ when starting from a stop sign, same as above, and car jerks a bit.
>> ___ the remote key doesn't always work, and when it does, the "beep"
>> when locked is more like a "mooooo".
>> ___ basically, it sems like there's not enough juice, but it doesn't
>> happen ALL the time.
>> ___ the kicker: it all goes away when the AC is off.
>>
>> AutoZone checked my battery and alternator with a machine that
>> attaches to the battery terminals and they told me both were fine.
>> So what can it be? I checked the fuses and connectors around
>> the battery. All look fine.
>> __________________________________________________ ______
>>
>> It does sound like a bad connection somewhere.
>>
>> You can't tell the quality of the connections by looking
>> at them. You have to disconnect every connector,
>> inspect and clean it, then reconnect it. This includes:
>>
>> Pos Cable to Pos Battery Post
>> Pos Cable to Start Relay Terminal
>> Pos Cable to Fusible Links.
>> Pos Cable to Alternator Terminal.
>>
>> Neg Cable to Neg Battery Post
>> Neg Cable to Engine Block
>> Engine Block to Chassis Cable
>>
>> Try these, then post again noting the results and
>> identifying the vehicle. You may get more help.
>>
>> Good luck.
>>
>> Rodan.
>
> OK, so I disconnected the battery and cleaned the connections with a
> wire brush.
> Still having problems.
>
> Now, I started the car with AC off, and disconnected the battery
> negative terminal. It started to chocke a bit, but still ran. Then,
> with neg. disconnected, I turn the AC on, and it died. So I
> reconnected the neg, turn the AC on, and started the car. Then i
> disconnected the neg. and it died instantly. I repeateed this 4 times
> with the same result.
>
> I'm guessing alternator. You?

Probably is now. On most of the newer vehicles disconnecting the
alternator for a few seconds is enough to blow the regulator or a diode
or two. The catch is that on many of the vehicles built after 95-96 the
regulator isn't in the alternator, it is inside the ECM. So if you blow
it you get to replace the computer!

I would look for a bad cable or bad ground strap from the block to the
chassis.

--
Steve W.
Near Cooperstown, New York

"Steve W." > wrote in message
...
> wrote:
>> On Aug 7, 6:19 pm, "Rodan" > wrote:
>>> > wrote: Alternator or Battery Problem ???
>>>
>>> Here's what happens with my car:
>>>
>>> ___ sometimes fails to start, but the dash lights come up.
>>> ___ when idling sometimes the power to AC, radio, and trans cuts off.
>>> ___ when starting from a stop sign, same as above, and car jerks a bit.
>>> ___ the remote key doesn't always work, and when it does, the "beep"
>>> when locked is more like a "mooooo".
>>> ___ basically, it sems like there's not enough juice, but it doesn't
>>> happen ALL the time.
>>> ___ the kicker: it all goes away when the AC is off.
>>>
>>> AutoZone checked my battery and alternator with a machine that
>>> attaches to the battery terminals and they told me both were fine.
>>> So what can it be? I checked the fuses and connectors around
>>> the battery. All look fine.
>>> __________________________________________________ ______
>>>
>>> It does sound like a bad connection somewhere.
>>>
>>> You can't tell the quality of the connections by looking
>>> at them. You have to disconnect every connector,
>>> inspect and clean it, then reconnect it. This includes:
>>>
>>> Pos Cable to Pos Battery Post
>>> Pos Cable to Start Relay Terminal
>>> Pos Cable to Fusible Links.
>>> Pos Cable to Alternator Terminal.
>>>
>>> Neg Cable to Neg Battery Post
>>> Neg Cable to Engine Block
>>> Engine Block to Chassis Cable
>>>
>>> Try these, then post again noting the results and
>>> identifying the vehicle. You may get more help.
>>>
>>> Good luck.
>>>
>>> Rodan.
>>
>> OK, so I disconnected the battery and cleaned the connections with a
>> wire brush.
>> Still having problems.
>>
>> Now, I started the car with AC off, and disconnected the battery
>> negative terminal. It started to chocke a bit, but still ran. Then,
>> with neg. disconnected, I turn the AC on, and it died. So I
>> reconnected the neg, turn the AC on, and started the car. Then i
>> disconnected the neg. and it died instantly. I repeateed this 4 times
>> with the same result.
>>
>> I'm guessing alternator. You?
>
> Probably is now. On most of the newer vehicles disconnecting the
> alternator for a few seconds is enough to blow the regulator or a diode or
> two. The catch is that on many of the vehicles built after 95-96 the
> regulator isn't in the alternator, it is inside the ECM. So if you blow it
> you get to replace the computer!


So right, Steve. Ever notice they are often referred to as--not
'alternator'--but battery maintainer? Plus, doing the 'good samaritan
thing' by boosting someone can blow your own alternator(or whatever they
wish to call it), esp. if their battery is close to completely dead! sam

> The catch is that on many of the vehicles built after 95-96 the
> regulator isn't in the alternator, it is inside the ECM. So if you blow
> it you get to replace the computer!

Link? I've never hear of the regulator being part of the computer.
That does not sound like a good design either, sicne the regulatore is
likely to throw off heat.

"zzyzzx" > wrote in message
...
>> The catch is that on many of the vehicles built after 95-96 the
>> regulator isn't in the alternator, it is inside the ECM. So if you blow
>> it you get to replace the computer!
>
> Link? I've never hear of the regulator being part of the computer.
> That does not sound like a good design either, sicne the regulatore is
> likely to throw off heat.

I believe GM still has the regulator internal to the alternator. In the
previous years, they certainly did so. Heat and vibration are two of the
main factors that kill regulators.

Chrysler and, I believe, Ford have at least some of their regulators
outboard or in the ECM.
They run cooler, in general, have less vibration, and are generally
perceived to last better.