The Cadillac DeVille from 1999 was a luxury sedan known for its comfort, spacious interior, and advanced features during its era. Its electrical system, which included the fuse box and relay components, played a crucial role in ensuring the vehicle’s functionality and reliability.
The fuse box in the 1999 Cadillac DeVille contained various fuses designed to protect specific electrical circuits throughout the car. These circuits powered essential components such as the engine control module, lighting systems, climate control, entertainment features, and more. Fuses were critical as they would interrupt the electrical flow in case of an overload or short circuit, preventing damage to sensitive components.
Relays in the 1999 Cadillac DeVille served as electrically operated switches that controlled high-current circuits. They enabled precise activation and deactivation of functions like the starter motor, fuel pump, air conditioning compressor, and power windows or seats. Efficient management of power distribution by relays contributed significantly to the overall performance and reliability of the vehicle.
Regular inspection and maintenance of the fuse box and relays were necessary to ensure the 1999 Cadillac DeVille operated smoothly. This involved checking fuses for signs of wear or damage, ensuring secure relay connections, and promptly addressing any electrical issues that arose. Proper care of these components helped maintain the vehicle’s electrical integrity, enhancing safety and driving satisfaction for owners of the 1999 Cadillac DeVille.
MUST READ: DYI – How to Check Car Fuses?
(1999) Cadillac DeVille 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.
Cadillac DeVille 1999 fuse assignment
- Cigar lighter / power outlet fuses in the Cadillac DeVille are the fuses №. 22 and 23 in the Engine compartment fuse box and fuse №65 in the Rear Underseat fuse box.
Year of production: 1999
Maxi Fuses/Relay Center
The MaxiFuses and relays are located next to the engine compartment fuse block on the driver’s side of the engine.
| MaxiFuse (8-Way) | Usage |
| BODY 1 | Road Sensing Suspension (RSS) Fuse (DeVille Concours Only), Convenience Fuse, BATT Fuse, Antenna Fuse, Right and Left Position Lamp Relays (Export), Hazard/Position Lamp Cut-Out Relay (Export), Trunk and Fuel Door Release Solenoids and Relays, Door Lock/Unlock Relays, Damper Relay (DeVille Concours Only), Parking Lamp Relay, Right and Left Park Fuse |
| BODY 2 | Defog Relay, Pull-Down Fuse, Right and Left Heated Seat Fuse, Electronic Level Control (ELC) Fuse/Relay, Heated Mirror Fuse, Heated Backlite Fuse, ELC Circuit Breaker |
| BODY 3 | Controlled Power Relay, Controlled Power Back-Up Relay, Cluster Fuse, Passenger Zone Module (PZM) Fuse, Radio Fuse, Delayed Accessory Bus (DAB) Relay, Trunk and Fuel Door Release Relay, High Beam Relay, Comfort Fuse, AMP (Bose Only) Fuse |
| INADVERT | Inadvertent Power Relay, Interior Lamps Fuse, Cigarette Lighter-1 Fuse, Cigarette Lighter-2 Fuse, Courtesy Lamp Relay |
| LAMPS | Headlamps Fuse/Relay, High/Low Beam Control Relay, Fog Lamp Fuse (DeVille Concours Only), Hazard Fuse, Mirror Fuse, Inadvertent Power Relay, Right and Left High Beam Fuse, Right and Left Low Beam Fuse, Stop Fuse, Fog Lamp Relay (DeVille Concours Only), DRL Relay, DRL Fuse |
| IGN 1 | Rear Ignition-1 Relay, Wiper Fuse, Relay Ignition-1 Fuse, Supplemental Inflatable Restraint (SIR) Fuse, Accessory Relay |
| WINDOWS | Delayed Accessory Bus (DAB) Relay |
| SEATS | Horn Relay, Driver and Passenger Lumbar In/Out Relays, Driver and Passenger Lumbar Up/Down Relays |
| MaxiFuse (6-Way) | Usage |
| BATT 3 | Steering Column Ignition Switch |
| BATT 2 | Steering Column Ignition Switch |
| IGN 1 | Front Ignition-1 Relay, Oxygen Sensor 1 and 2 Fuse, Fuel Fuse, Cruise Fuse, Fuel Pump Relay |
| BATT 1 | Starter Relay and Solenoid, Park/Rev Fuse, Park Relay, Powertrain Control Module (PCM) Fuse, AC Compressor Fuse and Relay, Cooling Fan Relays, Reverse Relay |
| BRAKES | Anti-Lock Brake System (ABS) Brake Modulator |
| COOL FNS | Cooling Fan Relays 1 and 3 |
| Power Distribution Block | Usage |
| ACCESSORY | Accessories |
| HEAD LPS | Headlamps |
| HORN | Horn |
| FOG LPS | Fog Lamps |
| DRL | Daytime Running Lamps (DRL) |
| HI/LO BEAM | High and Low-Beam Headlamps |
| Relays |
| INADVERT POWER RELAY |
| IGN 1 RELAY |
| STARTER RELAY |
Fuses and Circuit Breakers
Underhood Fuse Block
The underhood fuse block is located next to the engine air cleaner/filter on the driver’s side of the engine. Lift the cover to gain access.
| Fuse | Usage |
| DRL | Daytime Running Lamps (DRL) |
| CNR LPS | Cornering Lamp Switch, Right and Left Cornering Lamps, Right and Left Position Lamp Relays (Export) |
| INT LPS | Trunk Lamp, Courtesy Lamps, Front Vanity Lamps, Glove Box Lamp, Garage Door Opener, Courtesy Lamp Relay, Front Reading Lamps, Rear Vanity Lamps and Reading Lamps (DeVille Concours/d’Elegance Only) |
| CIG LTR1 | Front Cigarette Lighter, Rear Cigarette Lighter (DeVille Concours Only) |
| CIG LTR 2 | Right and Left Rear Cigarette Lighters |
| L HDLP LO | Left Low-Beam Headlamp |
| R HDLP LO | Right Low-Beam Headlamp |
| L HDLP HI | Left High-Beam Headlamp |
| R HDLP HI | Right High-Beam Headlamp |
| FOG | Fog Lamp Relay (DeVille Concours Only), Right and Left Fog Lamps (DeVille Concours Only) |
| HDLPS | Headlamp Relay, High/Low Beam Control Relay, Right and Left Low/High Beam Fuses |
| HAZARD | Electronic Flasher Module, Turn/Hazard Switch, Right and Left Front Turn Lamps, Right and Left Rear Turn Lamps, Right and Left Repeater Lamps (Export), Cluster |
| STOP | Stoplamp Switch, Turn Hazard Switch, Anti-Lock Brake System (ABS) Controller, Stepper Motor Cruise Control, Right and Left Rear Stoplamps (Export), Center High-Mounted Stoplamp |
| MIRROR | Inadvertent Power Relay, Left Outside Rearview Mirror Switch, ALDL, Memory Mirror Module (Optional), Dimmer Switch, Cluster |
| DRL | Daytime Running Lamp (DRL) Relay, Left and Right Low Beam in DRL Mode, DRL Resistor |
| IGN 0 (ENG) | Powertrain Control Module (PCM) |
| SPARE | Not Used |
| ABS | Anti-Lock Brake System (ABS)/Traction Control System |
| IGN-1 | Rear Ignition-1 Relay, Fog Lamp Relay (DeVille Concours Only), Controlled Power Backup Relay, DRL Relay, Ignition Switch in Steering Column, Injectors, ECS Fuse, PCM Fuse, DIS Fuse, Injector Fuses |
| WIPERS | Accessory Relay, Wiper Switch |
| A/C COMP | AC Compressor Relay, Cooling Fan Relays 1, 2, 3, Compressor Clutch |
| PCM (BAT) | Powertrain Control Module (PCM) |
| PARK/REV | Reverse Relay, Right and Left Back-Up Lamps, Electrochromic Mirror (in Header), Park Relay, Brake Transaxle-Shift Interlock (BTSI) Switch, BTSI |
| ECS | Transaxle Shift Solenoids, Mass Airflow, Canister Purge, PCM, Linear Exhaust Gas Recirculation (EGR), Front Ignition-1 Relay |
| PCM (IGN) | Powertrain Control Module (PCM) |
| DIS | Electronic Ignition Control Module |
| CRUISE | Stepper Motor Cruise Control, Power Steering Pressure Switch, Low Refrigerant Pressure Cutoff Switch, Park Relay |
| INJ | Injectors 1, 4, 6, 7 |
| INJ | Injectors 2, 3, 5, 8 |
| FUEL PUMP | PCM, Fuel Pump Relay, Fuel Pump |
| OXY SEN1 | Oxygen Sensor Front |
| OXY SEN2 | Oxygen Sensor Rear, Catalytic Converter (CAT) Rear Oxygen Sensor |
Rear Compartment Fuse Block
This fuse block is located on the front wall of the trunk (behind the rear seat) on the driver’s side. Loosen the four trunk trim fasteners and pull the trim away from the fuse block to gain access.
| Fuse | Usage |
| RLY IGN1 | Cluster, Cruise in Stalk, Passenger Zone Module (PZM), Traction Control (TCC) Switches |
| SIR | Sensing and Diagnostic Module (SDM), Right and Left Side Impact Sensing Modules |
| ELC | Electronic Level Control (ELC) Relay, ELC Sensor (DeVille Only), ELC Compressor |
| TURN | Electronic Flasher, Turn/Hazard Switch |
| CONSOLE | Rear Zone Blower, Right and Left Heated Seat Switches (Optional), Cellular Phone Handset (Optional) |
| SPARE | Not Used |
| SPARE | Not Used |
| RSS | Road Sensing Suspension (RSS) (DeVille Concours Only) |
| IGN 0-BODY | PRNDL Indicator (DeVille Concours Only), PZM, Cluster, Air Control Module (ACM), Upper Zone Motor, Lower Zone Motor (Optional), HVAC Solenoids, Climate Control Panel Analog Cluster (Console Shift Only), Rear Defog Relay, ELC Relay (DeVille Concours Only), Dual Zone Switch (DeVille and DeVille d’Elegance Only) |
| COMFORT | CD Player, Remote Keyless Entry (RKE), Controlled Power Relay, Air Control Module (ACM), PZM |
| AMP | Active Audio Amplifier (Optional) |
| PZM | Passenger Zone Module (PZM) |
| RADIO/PHONE | Radio Receiver, Phone, DAB Relay, Trunk Release Relay, Fuel Door Release Relay, High/Low Beam Relay |
| CLUSTER | Steering Wheel Controls, Cluster |
| ACC | PZM, Electrochromic Mirror, Rain Sensor (Optional), Accessory Relay |
| HTD BACKLT | Rear Window Defog |
| HTD MIR | Right and Left Heated Outside Mirrors |
| HTD SEAT R | Passenger Heated Seat Relay (Optional) |
| HTD SEAT L | Driver Heated Seat Relay (Optional) |
| PULL DOWN | Trunk Pull-Down Motor |
| HDLP WASH | Headlamp Washer |
| ANTENNA | Power Mast Antenna |
| RSS | Road Sensing Suspension Module (DeVille Concours Only), Damper Relay (DeVille Concours Only) |
| CONVENC | Trunk Release Relay, Trunk Release Solenoid, Fuel Door Release Relay, Fuel Filler Door Release Solenoid, Door Lock Relay, Left Front Door Motors, PZM, Door Unlock Relay |
| BATT | Driver and Passenger Seat Lumbar Switch (Optional), Memory Seat Module (Optional) |
| RSS | Road Sensing Suspension (DeVille Concours Only) |
| RT PARK | Headlamp Switch, Right Turn/Stop/Tail Lamps, Right Front and Rear Sidemarker Lamps, Right Front Park/Turn Lamps, License Plate Lamp, Hazard/Position Lamp Cut-Out Relay (Export) |
| LT PARK | Left Turn/Stop/Tail Lamps, Left Front and Rear Sidemarker Lamps, Hazard/Position Lamp Cut-Out Relay (Export), Left Front Park/Turn Lamps, Underhood Lamp, Trailer (Optional) |
Conclusion
For owners and enthusiasts of classic Cadillac DeVille 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 Cadillac’s craftsmanship and innovation in the automotive industry during that era.
