Why do my brake lights ,at mode and battery light illuminate but go offf after i reach 2500 rpm

Check the bulb ground connection. Power may be reaching the bulbs but you need a ground to complete the circuit.

Sounds like the altenator.

I doubt it is the belt because if the belt is slipping you should hear it.
The alternator could be about to crash and not charging at lower speeds.
You would check alternator output to find out.
The battery and brake warning lights are on the same circuit.

1) try to use the self diagnose.
2) place ignition swtuch in the start position, the lights coming on
3) engine starts, the brake light sould turn off inmediately. the ABS ligth will illuminate for aprox 6 seconds.
4) test drive the vehicle at speed above 20mph for a few minutes. during the test the both test lights should remain off, if any one of the warninign light utron, take note of the condition.
5) stop the vechicle using the braking pressure.both light should remain offf during the stopping procedure.
60 place the gear selector in to PARK, and observe the warning lights, they should both be off.
God bless you

sounds like wireing is shorted together. you need to trace down wires and check for bad spots in wireing. also be sure and check plug if you are set up for trailer lights.

go to auto zone and they will run the codes for free

actually it works in battery. check the coil associated with the RPM meter or if your battery charge is low recharge it. You ll get it fixed :) Please rate this!!

there is a short somewhere. faulty battery or faulty alternator.

You have a bad Alternator, the charging voltage is too low at idle so when you get to 2500 RPM its enough to take the lights off. Good Luck contact me if you need more help.

maybe a little corrosion on the connection from your alt? it could cause the higher resistance to make the voltage drop. the higher rpm's increase flow of electricity forcing it through the corrosion... maybe???