I have a 2003 envoy XL, I have replaced. the break switch & the turn signal switch, & 1 curcit board & I have power to the inside fuse box, and tail lights&turn signals work. but no brakes?
Power to the brake lights flows from Fuse 12 in the underhood fuse box to the brake light switch. Check for power at the switch on the orange wire. Power leaves the brake light switch on the white wire and heads rear fuse box under the left rear seat. Power goes to fuse 34 Vehicle stop fuse 15A. From there it goes to the left and right stop bulb connectors on the light blue wires. If you don't have power on the light blue wires, you've got a bad fuse or an open somwhere. Two fuses in the stop light cirucit.
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Power to the brake lights flows from Fuse 12 in the underhood fuse box to the brake light switch. Check for power at the switch on the orange wire. Power leaves the brake light switch on the white wire and heads rear fuse box under the left rear seat. Power goes to fuse 34 Vehicle stop fuse 15A. From there it goes to the left and right stop bulb connectors on the light blue wires. If you don't have power on the light blue wires, you've got a bad fuse or an open somwhere. Two fuses in the stop light cirucit.