The Chevrolet Suburban, built on the GMT400 platform from 1993 to 1999, is a hallmark of durability and versatility in the full-size SUV market. Known for its ability to handle everything from family road trips to heavy-duty towing, the Suburban during these years also featured a reliable electrical system, which is crucial for the operation of its various functions. The fuse box and relays play a key role in maintaining this system.
The fuse box in the 1993-1999 Chevrolet Suburban is designed to protect the vehicle’s electrical circuits. Typically, these models have two main fuse boxes: one located in the engine compartment and another in the interior, often under the dashboard. The engine compartment fuse box manages circuits related to the engine, transmission, and other high-power components, while the interior fuse box covers systems like lighting, power windows, and climate control. If any electrical component stops working, checking the relevant fuse is the first step, as a blown fuse can indicate an overload or short circuit in that specific circuit.
Relays in the Suburban are electrically controlled switches that manage the flow of power to high-current systems, such as the starter, fuel pump, and cooling fans. Relays allow these systems to be controlled by lower-power circuits, preventing the vehicle’s wiring and switches from being overloaded. A faulty relay can lead to issues like the engine not starting or the cooling system failing, both of which can cause significant operational problems.
Regular maintenance of the fuse box and relays ensures that the Chevrolet Suburban’s electrical systems remain in top condition, contributing to the vehicle’s long-standing reputation for reliability and performance.
MUST READ: DYI – How to Check Car Fuses?
(1993-1999) Chevrolet Suburban (GMT400) fuse box and relay with Diagram
WARNING
- Never replace a fuse with one that has a higher amperage rating.
- A fuse with a too-high amperage could damage the electrical part and cause a fire.
- On no account should fuses be repaired (e.g. patched up with tin foil or wire) as this may cause serious damage elsewhere in the electrical circuit or cause a fire.
- If a fuse blows repeatedly, do not keep replacing it. Instead, have the cause for the repeated short circuit or overload tracked and fixed.
- Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.
Chevrolet Suburban (GMT400) 1993-1999 fuse assignment
- Cigar lighter (power outlet) fuses in the Chevrolet Suburban are the fuses №7 “AUX PWR” (Aux Power Outlet) and №. 13 “CIG LTR ” (Cig Lighter) in the Instrument panel fuse box (1995-1999).
Year of production: from 1993, 1994, 1995, 1996, 1997, 1998, 1999
Instrument Panel Fuse Box
1993-1994
The fuse block is behind an access door at the bottom of the instrument panel, next to the parking brake release lever
Fuse box diagram
Assignment of the fuses in the Instrument Panel (1993, 1994)
| Name | Circuit protected | Ampere rating [A] |
|---|---|---|
| Gages | Cruise Control, 4 WD Display illum. Rear Window Defogger Timer, Aux. Batt. Relay Feed, Safety Belt Buzzer Timer, Cluster Ign. Feed | 20 |
| Turn-B/U | Back-up Lamps, Turn Signals | 15 |
| EMC/Ign | T.C.C., Air Diverter, E.S.C., E.G.R., E.C.M., Ign., R.W.A.L. Brake Switch | 10 |
| Inj. A | Throttle Body Injectors | 10 |
| Brake | A.B.S., Cluster-Speed0 | 15 |
| AC/Htr | H.V.A.C. 4 WD, Aux. Batt. Relay | 25 |
| Ctsy | Dome Lamp, Ctsy. and Glove Box Lps. (TR-9), Radio (Memory-Clock) | 20 |
| Park LP | Horn Relay, Horn Feed, Park Lamps | 20 |
| P. Lps | C49 SW Illum., Headlamp “On” Warning, Radio Illum., H.V.A.C. Illum. | 5 |
| Stop/Haz | Haz. Flasher, Seat Belt Buzzer, Stop Lmps., A.B.S. Memory | 15 |
| Wiper | Windshield Wiper, Washer | 25 |
| Radio | Radio Feed | 10 |
| Acc/Ign | Pwr. Windows | 30 (CB) |
| Acc/Batt | Door Locks, Rear Window Defogger | 30 (CB) |
| Crank | Crank, Discreet | 5 |
| 4WD | Four Wheel Drive | 25 |
| DRL | Daytime Running Lights | 15 |
| RR Wpr | Rear Window Wiperwasher | 25 |
| T/G Rel | Cigar Lighter, Rear Hatch Release | 25 |
1995-1999
The fuse block access door is on the driver’s side edge of the instrument panel.
Fuse box diagram
Assignment of the fuses in the Instrument Panel (1995-1999)
| № | Name | Circuit protected |
|---|---|---|
| 1 | STOP/HAZ | Stop/TCC Switch, Buzzer, CHMSL, Hazard Lamps, Stop Lamps |
| 2 | T CASE | Transfer Case |
| 3 | CTSY | Courtesy Lamps, Cargo Lamp, Glove Box Light, Dome/RDG Lamps, Vanity Mirrors, Pwr Mirrors |
| 4 | GAGES | Instrument Cluster, DRL Relay, Lamp Switch, Keyless Entry, Low Coolant Module, Illuminated Entry Module, DRAC (Diesel Engine) |
| 5 | RR WAC | RR HVAC Controls |
| 6 | CRUISE | Cruise Control |
| 7 | AUX PWR | Aux Power Outlet |
| 8 | CRANK | 1995-1996: Diesel Fuel Pump, DERM, ECM 1997: Air Bag System 1999: Crank |
| 9 | PARK LPS | Lic Lamp, Park Lamp, Tail Lamp, Roof Marker Lamp, Tdi1 Gate Lamps, Front Side Markers, Door Switch Illum, Fender Lamp |
| 10 | AIR BAG | DERM |
| 11 | WIPER | Wiper Motor, Washer Pump |
| 12 | HTR-A/C | A/C, A/C Blower, High Blower Relay |
| 13 | CIG LTR | Power Amp, Rear Liftglass, Cig Lighter, Door Lock Relay, Pwr Lumbar Seat |
| 14 | ILLUM | 4WD, Indicator, LP Cluster, HVAC Controls, RR HVAC Controls, IP Switches, Radio Illumination, Chime Module |
| 15 | DRL-FOG | DRL Relay, Fog Lamp Relay |
| 16 | TURN-B/U | Front and Rear Turn Signals, Back-up Lamps, BTSI Solenoid |
| 17 | RADIO | Radio (Ign) |
| 18 | BRAKE | DRAC (1995-1996), 4WAL PCM, ABS, Cruise |
| 19 | RADIO BATT | Radio (Batt) |
| 20 | TRANS | PRNDL, Auto Transmission, Speedo, Check Gages Tell Tale, Warning Lights |
| 21 | 1995-1996: Not Used 1997: Variable Effort Steering 1999: Security/Steering | |
| 22 | — | Not Used |
| 23 | RR Wiper | Rear Wiper, Rear Wash Pump |
| 24 | 4WD | Front Axle, 4WD Indicator Lamp, TP2 Relay (Gasoline Engine) |
| A (CB) | PWR ACCY | Pwr Door Lock, 6-Way Pwr Seat, Keyless Entry Module |
| B (CB) | PWR WDOS | Power Windows |
Engine Compartment Fuse Box
Fuse box location
Fuse box diagram
Assignment of the fuses and relay in the Engine Compartment (1995-1999)
| Name | Circuit protected |
|---|---|
| ECM-B | Fuel Pump, PCM/VCM |
| RR DEFOG | Rear Window Defogger (If Equipped) |
| IGN-E | Auxiliary Fan Relay Coil, A/C Compressor Relay, Hot Fuel Module |
| FUEL SOL | Fuel Solenoid (Diesel Engine) |
| GLOW PLUG | Glow plugs (Diesel Engine) |
| HORN | Horn, Underhood Lamps |
| AUX FAN | Auxiliary Fan |
| ECM-1 | Injectors, PCM/VCM |
| HTD ST-FR | Heated Front Seats |
| A/C | Air Conditioning |
| HTD MIR | Heated Outside Mirrors (If Equipped) |
| ENG-1 | Ignition Switch, EGR, Canister Purge, EVRV Idle Coast Solenoid, Heated O2, Fuel Heater (Diesel Engine), Water Sensor (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 | Hi Blower and Rear Blower Relays |
| STOP/HAZ | Stoplamps |
| HEATED SEATS | Heated Seats (If Equipped) |
Conclusion
For owners and enthusiasts of classic Chevrolet Suburban (GMT400) 1993-1999, understanding the fuse box and relay systems is essential for vehicle maintenance. Regular inspection and maintenance of these components helped ensure the vehicle’s longevity and reliability, preserving its status as a symbol of Chevrolet’s craftsmanship and innovation in the automotive industry during that era.
