2001 Nissan Maxima dashboard dash light shows brake and battery symbols??

And then my question is how much will a new alternator cost with labor and can I trust a non-Nissan shop to do this or best I let Nissan do it (had bad experiences b4 with others doing the brakes since they did not use Nissan brake pads)?

Thanks, Patty

snipped-for-privacy@hotmail.com wrote:

This is a classic alternator going bad problem. To verify, just hook up a voltmeter to the battery terminals with the engine running, and you'll probably get 12 volts or less. A good alternator will generate a charging voltage of 13.5 to 14 volts. Thats the reason the battery lite comes on. The brake warning lite also comes on because of the low voltage on the brake sensor. This happened to my 2K Max, and a new battery at least got me home without having to have it towed. BTW, I installed an AutoZone alternator a year ago and it still worked fine.

Thanks. Now after the car sitting idle for about 5 hours, the brake and the battery lights do not come on. So not sure what to think at this point. I could of course buy a voltmeter and hook it up and look for the charging voltage. Guess you cannot unhook the battery after cranking and check voltage since you will lose the negative ground probably.

Ideas on the above and also that light is not appearing now????? Should I wait for it to appear again?

Brake fluid is fine.

Thanks, Patty

cmdrdata wrote:

- dont disconnect batt while engine running, possibly fries some electronics

- charge voltage is seen on batt while idling. Nissan FSM says 13.8-14.7V is ok. - (14.8V is already boiling battery...)

- 10$ gauge investment is a must. (remember the cheap dmm's may be unreliable)

- the copper dust worn from alt/brushes (plus all dirt) 'fills' the alt inside 'after 60k'. This may form 'bridges' enhancing alt charge/discharge /rectifier diode etc -characteristics. Remedy: open, clean, swap 5$brushes

The alt is structurally almost like this; see

- dont disconnect batt while engine running, possibly fries some electronics

- charge voltage is seen on batt while idling. Nissan FSM says 13.8-14.7V is ok.

- (14.8V is already boiling battery...)

- 10$ gauge investment is a must. (remember the cheap dmm's may be unreliable)

- the copper dust worn from alt/brushes (plus all dirt) 'fills' the alt inside 'after 60k'. This may form 'bridges' enhancing alt charge/discharge /rectifier diode etc -characteristics. Remedy: open, clean, swap 5$brushes

The alt is structurally almost like this; see

Bought voltmeter and noticed little difference on battery when car was running and when car was off. Slightly higher when car was running. Voltage went up when I revved engine (pulling on accelerator cable) so that seems good.

So all in all, things seem okay but I do not think I am out of the woods since light did come on yesterday and now all seems okay.....I need some consistency but hate (am unemployed) to invest in an alternator if it appears to be working.

Thanks, Patty

Wiik> - dont disconnect batt while engine running, possibly fries some electronics

ok. - (14.8V is already boiling battery...)

'after 60k'. This may form 'bridges' enhancing alt charge/discharge /rectifier diode etc -characteristics. Remedy: open, clean, swap 5$brushes

I had the same problem...same lights....

The alternator was bad. What is happening is the alternator is not fully charging the battery, and the voltage being sensed in the ABS is low, so the brake light comes on as well.

Replaced the alternator, and the problem went away.

Good luck.

Replace the alternator and all will be fine.

Be sure to use an OEM part or..............

Anyone care to fill in the blank?

NISSTECH-Should I wait until light comes on again since things seem to be working okay for the last 2 days?

Thanks, Patty

NissTech wrote:

Normal when the alternator is dying.

I wouldn't. I also wouldn't use anything other than a nissan reman but if you enjoy replacing alternators, the parts store ones are cheaper..

If one rectifier diode is blown [or dust shorting it], the alt may well be pushing half rectified AC into system. No good for batt. Only way to make sure is with an oscilloscope as dmm always shows something when measured in AC-scale.

Connectors: If u follow via the 'Favorite Links' youll find all detail info + alt assembly pics.... Go peek under the vehicle, pass side after taking splash shields out: there are the supply connectors.

I suggested cleanin the alt - dirt cheap:) no harm done.

Patty:

What you measured with the volmeter seems pretty normal to me.

Given that the problem is intermittent, I would check all the field connections to the alternator, those are the connections that tell the alternator to charge and normally come from the ignition and are the thin wires getting to it. While at it, check the fuses related to the alternator too.

I assume you discarded the possibility of having low brake fluid level. The behaviour you describe, some days on, etc. is typical of low brake fluid level too.

Good luck

Wiik> If one rectifier diode is blown [or dust shorting it], the alt may well be

pushing half rectified AC into system. No good for batt. Only way to make sure is with an oscilloscope as dmm always shows something when measured in AC-scale.

alt assembly pics.... Go peek under the vehicle, pass side after taking splash shields out: there are the supply connectors.

Thanks all. Got a rebuilt Bosch alternator for $360 including labor for the Maxima. Voltage is correctly reading now when car on and loaded with AC and radio and lights on....... Learned a lot.

Next thing I think is perhaps a pulley-hear a slight metallic grinding noise some times when I turn A/C on. Lasts about 3 seconds (on occasion) after I start car.

Take care Patty

_____________________________________ AS wrote:

pushing half rectified AC into system. No good for batt. Only way to make sure is with an oscilloscope as dmm always shows something when measured in AC-scale.

• alt assembly pics.... Go peek under the vehicle, pass side after taking splash shields out: there are the supply connectors.

Is it a metallic grind or a high pitched squeal?? It seems the mechanic who replaced the alternator did not properly tighten the belt. Offset should be between 1/8 and 1/4 inch.

Mike