GE 169137 Classic 4-Slice

have you tried to turn up the heat thermostat on the side.

If holding down the handle all the way causes the toasting coils to heat up, the problem to stay down is the result of a IC chip failure on the circuit board that is not specifically identifiable. The IC controls current through a solenoid (electromagnet) that holds down a metal plate attached to the handle.

If the coils DON't heat up, the problem could be one or both of the metal push-down contacts on the circuit board that are activated by the handle. Plastic case is difficult to get off. Four screws on the bottom for starters, then you must "get behind" the toaster hand and push the back of it to one side to disengage it from its mechanism. THe front adjusting have to be pulled (forced) off by applying a screwdriver blade behind the knob and prying forward.

Good luck from there!