I need help. I was just leaving for a trip and my brake light and battery light just lit up on the dash after I put the car in drive after idling for 10 mins in extreme heat. The battery was new in Sept.2000. My car is a 97 gle with 50000 miles on it. I have checked a few of the fuses and they seem fine. The car seems to work perfect even though these lights are on. Any assistance will be appreciated. So that I may leave on my trip ASAP.
Thanks,
Chad

 

The battery light indicates a charging problem. Check the connections at the battery, and make sure the accessory belt is properly tensioned.

The brake light indicates that either you have the parking brake on, or that you are low on brake fluid. If you have ABS problem, the ABS light will come on.

 

When my Battery and Brake lights both came on this last spring, it turned out to be an alternator with no output. Replacing the alternator solved the problem. My '96 Maxima only had 25K miles at the time with a 1-1/2 year old battery. Before finding the problem, charging the battery made the two lights go out for a few miles until the battery drained down then the Battery and Brake lights came back on. The battery is still fine.
The original alternator must have been a dud to have died so young for no apparent reason, it appears that the diodes blew. I have the 1996 Maxima factory service manual, and there is no explanation in it as to why the Brake warning light also came on, at least that I could find. Be sure to check alternator belt tightness/condition and battery cable condition before doing an alternator output test.

 

This information is correct but there is more to the story. When both of these dashboard warning lights come on at the same time the problem is almost certainly a bad alternator, and more specifically the diode pack inside the alternator. Some auto parts stores offer a no-cost charging system test. This is done with an electronic test instrument and takes only two minutes. Please have this test done.

 

To elaborate on the point a bit: Although the "Trouble Diagnoses" section of the '96 Maxima FSM doesn't mention the connection between the "Battery" light and "Brake" light, the Wiring Diagram for the Warning Lamps (EL-WARN-03) shows that the "Brake" lamp will also light up if the alternator provides insufficient voltage (and a ground path) causing the "Battery" light to illuminate . There is a path for ground passing through a diode between the "Battery" and "Brake" warning lamp circuits.