On my 1991 honda accord the pass side brake light and center brake light sometimes work and sometimes dont. the driver side works great. need help.

You can try to replace all the brake lamp bulbs as sometimes eventhough all bulbs are working but one of them is about to blow and give high resistance. That's why the brake lamp lights up.

it shouldn't,, But with Honda who knows, normally unless its just a bulb they all either work or not, so if you have the right side out, change the bulb,, if it works the center one is out too, be sure when replacing the bulbs to check them before you put them in, and clean any dark or burn spots in the holder, Ive had numerous times a "new" bulb was no good,

I had this problem before. I found the wiring harness at the rear light to have a short in the wiring. Certain ways you move the wires would allow it to work intermittently. After changing the harness, no more problems.

I assume you have replaced the lamps/globes with new ones, if not this is the first thing to try.
If your car is fitted with a "faulty light" sensor, ( i.e. if a warning light on the dashboard comes on when you apply the brake and a brake light bulb is not working), this may be the problem. Follow the wiring for the rear lights from the light clusters inside the trunk and you may find the wiring harness plugged into an encapsulated unit in the rear somewhere. Test if power is coming out of this unit when brakes are applied. Or, remove the covers on the brake light clusters from inside the car and check the wiring to the rear window brake light. Very often this is connected to the same ground as the drivers side light. However, the parking and tail and reversing lights usually work off the same ground, so this seems unlikely.

check the electrical connector on the taillight assembly for corrosion, just had the same problem on my sons car last month. clean them up as best you can and apply some electrical grease into yhe holes of the female plug

check the bulbs first

its the HIC VALVE....it controls your idle common to older vehicle and almost work like a sensor. when the engine is on , coolant runs through it as the temp rises-it lowers the idle. calcium builds up in the coolant ports and restricks the coolant. located on the drivers side, on the intake manifold. (usually u can remove it, take it apart and clean or replace it, sometime you may catch one on ebay for cheap.

After you have checked the fuseand the bulb connection, you may also want to check the brake switch located at top of the brake padel under the dashboard. Once you push the brake padel, the switch will trigger and the brake light will be on. Use simple 12 volt test pen or voltmeter to test the current supply. Enjoy it.

Check the prones inside the connector that you plug into the brake light module. You may have to squeeze, wiggle, tilt each one to see which one is not connecting all that good. I know it may sound confusing. I tried to explain the best of I could.

On the driver's side, at your left foot is a compartment with a twist open, plastic lock; turn it and pull to reveal fuses