Back-up lights don't work lights used to come on when brake was released lights used to flash when alarm turned on if its a fuse, which one?

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The voltage is supplied at all times through the STOP HAZ Fuse 1 to the TCC brake and cruise control release switch. The contacts in the TCC brake and cruise control release switch close when the brake pedal is depressed. The voltage is supplied through the hazard switch and the turn signal switch to the left and right stoplamps. The stoplamp will flash as a turn signal lamp if the turn signal switch is on. The stoplamp on the opposite side will serve as a stoplamp.

its caused by the security alarm? can you turn the alarm off somehow?

Sounds as if the bulbs are bad, but could also be a failed multi-purpose switch.

Most likely this is a brake light switch issue. Replace switch.

If your emergency flashers don't work, all flasher bulbs are fine, but flashing too fast, then check and replace Hazard light switch.

may have to purchase an electrical shopm manual for more information

might be an inline fuse

Have yoiu changed/checled the lightbulbs? (In other words,do your turn signal lights work? If the front turn signal lights work, but the rear don't, then turn on your four (4) way flashers. If the rear lights still don't work, then all the bulbs are bad. It is rare for all the bulbs to be burnt out at the same time, but it does happen.

If the turn signal/four way flasher lights work, then you probably have a bad brake light switch. However, first check your owner's manual to make certain there is not a separate fuse for these lights. If there is, then swap the fuse for the brake lights for another fuse (or relay) of the same size/amperage. (Facing the hood, the power relay box is located on the right side (usually) under the hood.)

The fuse box is located under the dash, on the driver's side of the car. Usually there is a plastic cover that has to be removed to access the underside of the dash, and then there is a plastic cover that has to be removed to access the fuse box. If you don't have an owner's manual, nprmally the fuses and power relays are normally marked on the plastic covers your remove ot access the fuses and power relays.

If the fuses/relays are good, then you have a bad brake light switch. This is located on a bracket just above the brake pedal. When you push the pedal down, the switch makes contact. Disconnect the plug to the switch, and jump across the plug contacts (not the switch) with a small piece of wire, or if a piece of insulated wire is unavailable, you can use a paperclip, you won't get schocked, just make certain that the paperclip does not come in contact with a ground while you have it plugged in to the plug for the brake light switch.

If the lights stil dont work, check for power to the plug for the brake light switch. If you have power to the plug, the turn signals and four-way flashers work, then my guess would be that you have a broken power wire (probably iside the steering column, or a bad turn signal switch. If the brake lights work whe nyou jump out the brake light switch, then the brake light switch is defective.

Reconnect all the ground wires on the back lights. They are using the parking lights as a ground.

OK try this, push and hold brake then push on the hazard switch if brake lights come on then replace the turn signal switch.

The brake light switch on these trucks was a poor design. Its mounted on the brake pedal. Look under there and bend the bracket that holds the brake light switch slightly and things will start working again. When these were new we used to just grab the brake pedal and pull it toward the drivers seat really hard and let go. This fixed your problem 99% of the time.