2000 Ford Expedition-Left turn signal and brake light in rear does not work, and left front flasher works but flashes quickly. The front and rear right side of turn signal and brake works perfectly. I changed bulb for left rear and on left top of vehicle for brake bulb, but still does not work. Also, my wipers do not stop on their own (as if off by one on each speed setting, because each speed works but not the "off" setting-it just stays on "1st speed setting) & I have to take fuse out of box for them to stop completely. Have changed "multi switch" but did not work either, so don't know if I got a bad one or if it may be wiring???

The flasher is under the dash.If you turn on the signal listen for it's location.Turn on your 4 way flasher and see if the left rear light is flashing.If it's not then replace the bulb.If it still does'nt work after replacing the bulb check if there is power to the socket. Use a probe light.If no power to the socket.There is a break in the wire or worse the signal switch may be the culprit

Has the vehicle been in an accident on the left rear side. First check the bulb to be sure it is not defective, trade it out with the side that works properly to test. If the bulb works well then My thought are you may have a shorted wire. The turn signal flasher works by heat build up within the flasher the heat is caused by the load of the bulbs, the load heats the metal spring causing it to open the circuit then as quickly as it cools down the circuit closes again lighting the bulbs.
There is also a possibility of a defect in the turn signal mechanism on the steering column. The turn signal switch on many models does three different things on many models that use the same bulb element / or bulb for brake and turn on rear of vehicle. It controls the circuit for brake light by sending power both left and right side rear when turn signal is in neutral position then when turn signal is in left turn the switch cancels brake light power to left side rear and supplies flasher power to left side while maintaining brake light supply to the right side rear, and so on opposite when the right turn is chosen on turn signal switch. The turn signal indicators on the dash normally run off the same circuit as front turn signal bulb only which is also controlled by turn signal switch. Front has turn signals but no brake light.
I think there is an additional load on the left side rear turn circuit and it could be either a wire that is shorted or the turn signal switch if the same bulb element is used for both functions.
Often times if trailer lighting is connected the flasher will also blink a little faster because of the extra load of additional bulbs.

Get a wiring diagram from the Free portion of the Autozone site. It is a little work to separate the Help categories at the bottom of their Webpage.

I have heard of SOME 4-way flashers that are built into the turn stalks causing problems. The contact pins for the turn signals are shared as 4-way flasher pins. Try clicking the 4-way flashers off/on about 20 times and then use the left turn signal. It has been known to reseat the contact pins.

The wiring diagram I mentioned would show where the tailgate top light gets its power. One feed should go to the brake light switch for the brakes and another feed should be the flasher feed.

As I see it, you have 2 extra lights going on when you use the left turn signal. Those 2 lights are the tailgate light and right turn signal. The wiring diagram should show the places where the wires are close enough to cross. I am thinking the 4-way flasher is the only place where the top tailgate light gets flasher power; the rest of the time the tailgate light is a Brake light.

I do not want to spend your money on an unnecessary turnstalk and that is why I say to look at a wiring diagram and see if there is anyplace where the wires could cross.

Last, trailer hitch plug. All wires are bundled with left turn, right turn, and brake light in the trailer hitch plug. Corrosion could connect the terminals.

Would like to know what you found.

because of no light flasher on left side the front one will go faster .maybe the left rear light is burn. and brake lights are control by the brake switch on brake pedal hardware, might be unadjust

It is very common for the light bulb socket to become minorly burned. You need to replace the socket. They are less than 10$. Hope this helps. TJ

under the dashboard

The rear left turn signal bulb must be replaced immediatly before it melts the light socket, if it has'nt yet. Also please verify that the correct light bulb is being installed. because even though many bulbs look the same they are not identical. Installing the wrong bulb can be the begining of many, many problems in the particular circuit

The quick flash is a fault detection for a burnt out bulb. If bulb is good, check bulb socket. Inspect for corrosion. If needed, replace bulb socket. Check bulb socket connector. Check if fuse. Check emergency flashers ( most cars have a separate circuit).

probably needs a turn signal switch

either the front or the rear turn signal bulb is blown, that is why the flash frequency is high. replace the bulb and the problem will be solved. best to replace both the front and rear turn signal bulbs. good luck.