GMC Sierra mk1 (1999 – 2000) – fuse box diagram
Year of production: 1999, 2000
Instrument Panel Fuse Block
The fuse block access door is on the driver’s side edge of the instrument panel. Pull off the cover to access the fuse block.
| Fuse/Circuit Breaker | Usage |
| 1 | Stop/TCC Switch, Buzzer, CHMSL, Hazard Lamps, Stoplamps |
| 2 | Transfer Case |
| 3 | Courtesy Lamps, Cargo Lamp, Glove Box Lamp, Dome/Reading Lamps, Vanity Mirrors, Power Mirrors |
| 4 | Instrument Cluster, DRL Relay, Lamp Switch, Keyless Entry, Low Coolant Module, Illuminated Entry Module, DRAC (Diesel Engine) |
| 5 | Not Used |
| 6 | Cruise Control |
| 7 | Auxiliary Power Outlet |
| 8 | Crank |
| 9 | License Lamp, Parking Lamps, Taillamps, Roof Marker Lamps, Tailgate Lamps, Front Sidemarkers, Fog Lamp Relay, Door Switch Illumination, Fender Lamps, Headlamp Switch Illumination |
| 10 | Not Used |
| 11 | Wiper Motor, Washer Pump |
| 12 | A/C, A/C Blower, High Blower Relay |
| 13 | Power Amp, Cigarette Lighter, Door Lock Relay, Power Lumbar Seat |
| 14 | 4WD Indicator, Cluster, Comfort Controls, Instrument Switches, Radio Illumination, Chime Module |
| 15 | DRL Relay, Fog Lamp Relay |
| 16 | Front and Rear Turn Signals, Back-Up Lamps, BTSI Solenoid |
| 17 | Radio (Ignition) |
| 18 | 4WAL/VCM, ABS, Cruise Control |
| 19 | Radio (Battery) |
| 20 | PRNDL, Automatic Transmission, Speedometer, Check Gages Warning Light |
| 21 | Security/Steering |
| 22 | Not Used |
| 23 | Not Used |
| 24 | Front Axle, 4WD Indicator Lamp, TP2 Relay (Gasoline Engine) |
| A | Power Door Lock, Six-Way Power Seat, Keyless Entry Module |
| B | Power Windows |
Underhood Fuse/Relay Center
The underhood fuse/relay center is located in the rear of the engine compartment near the brake fluid reservoir.
| Name | Usage |
| ECM-B | Fuel Pump, PCM/VCM |
| RR DEFOG | Rear Window Defogger |
| IGN-E | Auxiliary Fan Relay Coil, A/C Compressor Relay, Hot Fuel Module, Dual Tanks |
| HORN | Horn, Underhood Lamps |
| AUX FAN | Auxiliary Fan |
| ECM-1 | Injectors, PCM/VCM, Fuel Solenoid (Diesel Engine, Fuel Control Module (Diesel Engine) |
| HTD ST-FR | Not Used |
| A/C | Air Conditioning |
| HTD MIR | Not Used |
| ENG-1 | Ignition Switch, EGR, Canister Purge, EVRV Idle Coast Solenoid, MAF, Heated O2, Fuel Heater (Diesel Engine), Water Sensor (Diesel Engine), Boost Solenoid (Diesel Engine), EPR (Diesel Engine) |
| HTD ST-RR | Not Used |
| LIGHTING | Headlamp and Panel Dimmer Switch, Fog and Courtesy Fuses |
| BATT | Battery, Fuse Block Busbar |
| IGN-A | Ignition Switch |
| IGN-B | Ignition Switch |
| ABS | Anti-Lock Brake Module |
| BLOWER | High Blower Relay |
| STOP/HAZ | Stoplamps |
| HEATED SEATS | Not Used |
WARNING: Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.