Cadillac Seville (1986-1991) fuse box and relay Diagrams

Cadillac Seville 1986 1991

The Cadillac Seville from 1986 to 1991 continued to uphold its reputation as a luxurious and technologically advanced sedan. Its electrical system, incorporating the fuse box and relay components, was pivotal for ensuring smooth operation and functionality.

In this generation, the fuse box in the Cadillac Seville housed fuses that safeguarded various electrical circuits throughout the vehicle. These circuits powered critical components such as the engine control module, lighting systems, climate control, and entertainment features. Fuses were designed to protect against electrical overload by interrupting the circuit if necessary.

Relays in the Cadillac Seville acted as electrically operated switches responsible for managing high-current circuits. They facilitated the precise activation and deactivation of functions such as the starter motor, fuel pump, air conditioning compressor, and power windows or seats. This efficient power distribution ensured reliable performance of the vehicle’s electrical systems.

Regular inspection and maintenance of the fuse box and relays were essential to uphold the Cadillac Seville’s operational efficiency. This involved checking fuses for signs of wear or damage, ensuring relay connections were secure, and promptly addressing any electrical issues that arose. Proper care of these components contributed to maintaining the vehicle’s electrical integrity, enhancing safety and driving satisfaction in the Cadillac Seville 1986-1991.

MUST READ: DYI – How to Check Car Fuses?

(1986-1991) Cadillac Seville 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 Seville 1986-1991 fuse assignment

  • Cigar lighter / power outlet fuses in the Cadillac Seville is the fuse №.4.

Year of production: 1986, 1987, 1988, 1989, 1990, 1991

Passenger Compartment Fuse Box

cadillac seville fuse box diagram passenger compartment fuse box 1986
cadillac seville fuse box diagram passenger compartment fuse box 1986
No. A Protected Component
1 10A Electric Height Sensor, Electronic Level Control (ELC) Compressor
2 20A Courtesy Lamps, Interior Light, Trunk Light
3 10A Antenna Relay
4 20A Rear Door Cigarette Lighter (’86-’89), Console Cigarette Lighter (’86), Chime Module (’88-’91), Fuel Door Release Switch (’86-’87), Glove Box Lamp (’86)
5 15A Central Power Supply
6 20A Electronic Level Control (ELC) Compressor Relay
7 5A ’90-’91: Programmer (HVAC)
15A ’86-’89: Auto Day/Night Mirror, Chime Module, Brake Switch (Cruise Control), Theft Deterrent Module, Theft Deterrent Relay
8 3A Multi-Function Switch, Battery No Charge, Cruise Control
9 7.5A Programmer (AVAC), Rear Window Defogger Relay, Electric Height Sensor
10 3A Body Control Module (BCM), Overspeed Jumper (Saudi)
11 10A Radio
12 25A Windshield Wiper/Washer Switch
13 15A Trunk Release Switch
14 10A Courtesy Lamp Relay, High Beam Relay, Low Beam Relay, Retained Accessory Power (RAP) No.1 & 2, Twilight Headlight Relay, Twilight Park Light Relay
15 15A ’90-’91: Twilight Park Light Relay, Left Switch
20A ’86-’89: Twilight Park Light Relay, Left Switch
16 20A Brake Switch (Stop Lamps), Turn/Hazard Module (’86)
17 10A Radio Power, Keyless Entry Module (’90-’91)
18 10A Turn/Hazard Module, Fuel Tank Unit, Air Bags (DERM (’90-’91)), Gear Selector Switch, Body Control Module (BCM), Information Center, Keyless Entry Module (’90-’91), Auto Door Lock Module (’86-’89), Seat/Mirrors Memory Module (’87)
19 15A ’90-’91: Air Bags (DERM), Dual Sens
15A ’89: Parking Lights, Front/Rear Side Markers, Opera Lamp, Tail Lights, Engine Compartment Lamp, License Plate Lamp, Instrument Panel Cluster, Trailer Connector
10A ’86-’88: Parking Lights, Front/Rear Side Markers, Opera Lamp, Tail Lights, Engine Compartment Lamp, License Plate Lamp, Instrument Panel Cluster, Trailer Connector, Telephone
20 30A ’90-’91: Rear Window Defogger Relay
25A ’88-’89: Bose Amplifier
Circuit Breaker
21 10A Low-Beam Lights, Twilight Headlight Relay, Left Switch
22 20A High-Beam Relay
23 30A Power Seats, Door Lock Relay, Radio Amplifier (’86-’87), Seat/Mirrors Memory Module (’87)
24 30A ’90-’91: Retained Accessory Power (RAP) Relay
30A ’88-’89: Horn Relay
30A ’86-’89: Rear Window Defogger Relay, Horn Relay
25 30A ’86-’89: Retained Accessory Power (RAP) Relay No.2, Accessory Relay (’86)

Passenger Compartment Relay Box

cadillac seville fuse box diagram passenger compartment relay box 1986
cadillac seville fuse box diagram passenger compartment relay box 1986
No. A Circuits protected
1 10A ’90-’91: VCC Brake Switch, Chime Module, Theft Deterrent Module, Auto Day/Night Mirror
10A ’86-’89: Power Mirror Heater
2 15A ’90-’91: Fuel Pump Relay, Oil Pressure Switch
2A ’86-’89: Cellular Phone Transceiver
3 10A ’90-’91: Fuel Door Release Switch
20A ’88-’89: Fuel Door Release Switch
’87: Seat/Mirrors Memory Module
4 20A Trunk Pull-Down Unit
5 25A ’90-’91: Amplifier Relays (Delco Bose)
6  –
7 10A ’90-’91: ABS Module, Computer Command Ride (CCR) Module, Heated Windshield Module
8 3A ’90-’91: Body Control Module (Pin 1C9), Diagnostic Energy Reserve Module (DERM)
Relay
R1 ’86-’87: Radio Amplifier
R2 ’86-’89: Electronic Level Control (ELC) Compressor
R3 High Beam
R4 Retained Accessory Power (RAP) No.2 (Power Window, Sunroof)
R5 ’90-’91: Fuel Pump
’86-’89: Fuel Tank Unit, Engine Control Module
R6 Retained Accessory Power (RAP) No.1
R7 Twilight Crank
Rear Window Defogger, Power Mirror Heater
R8 Twilight Headlight
R9 Low Beam
R10 Twilight Park Light

Engine Compartment Fuse Box

cadillac seville fuse box diagram passenger compartment relay box 1986
cadillac seville fuse box diagram passenger compartment relay box 1986
No. A Circuits protected
1 10A ’90-’91: A/C Compressor Clutch Relay
10A ’86-’89: Fan Control Module, A/C Compressor Clutch Relay
2 15A ’90-’91: Cooling Fan (B), Low Refrigerang Switch
15A ’86-’89: A/C Compressor Clutch Relay
3 10A ’90-’91: EGR Solenoid, Auto Transaxle, Canister Purge Solenoid, P/S Pressure Switch
’88-’89: Engine Control Module
10A ’86-’87: Air Switch Solenoid, Air Diverter, EGR Solenoid, Canister Purge Solenoid, Power Steering Cutout Switch
4 20A ’90-’91: Horn
’86-’89: Fuel Pump Relay, Engine Control Module, Oil Pressure Sender
5 7.5A ’86-’89: Fuel Injectors
6 7.5A ’86-’89: Fuel Injectors
7 10A ’90-’91: Powerttrain Control Module (PCM (Pin A6) , Pass Key Decoder Module
’86-’89: Engine Control Module
8 ’86-’89: Body Computer Module, Electronic Brake Control Module
Relay
R1  –
R2  –
R3 ’90-’91: Cooling Fan (B)
’88-’89: Horn
’86-’87: Fan Control Module
R4 ’88-’91: A/C Compressor Clutch
’86-’87: EFE Heater
R5 ’90-’91: Cooling Fan (C)
’88-’89: Fan Control Module
R6 ’90-’91, ’86-’87:  Horn
R7 ’90-’91: Cooling Fan (D)
R8  –
R9 ’86-’87: Courtesy Lamps
R10 ’86-’87: Horn

Fusible Link (’90-’91)

  1. RED (RUST) – Cooling Fan Relays
  2. ORG (RUST) – Pass Key Decoder, Powertrain Control Module (PCM)
  3. RED (RUST) – Ignition Switch, Fuse No.: “5”, “14”, “17”; Fuse (Passenger Compartment Relay Box) No.: “5”
  4. RED (RUST) – Theft Deterrent Module, Fuse No.: “1”, “20”; Fuse (Passenger Compartment Relay Box) No.: “3”
  5. RED (RUST) – Fuse No.: “15”, “21”, “22”
  6. RED (RUST) – Fuse No.: “23”
  7. ORG (RUST) – Power Module, Fuse No.: “16”
  8. RED (RUST) – Ignition Switch, Retained Accessory Power (RAP) Relay No.1, Retained Accessory Power (RAP) Relay No.2
  9. RED (BLK) – Brake Modulator
  10. RED (BLU) – Brake Modulator
  11. RED (RUST) – Heated Windshield Module

Fusible Link (’88-’89)

  1. RED (ORG) – Power Module
  2. RED (ORG) – Cooling Fan Relays
  3. RED (ORG) – Fuse (Engine Compartment Fuse Box) No.: “2”
  4. ORG (ORG) – Engine Control Module
  5. RED (ORG) – Fuse (Passenger Compartment Relay Box) No.: “2”
  6. RED (ORG) – Ignition Switch, Fuse No.: “5”, “14”, “17”, “20”
  7. RED (ORG) – Theft Deterrent Module, Fuse No.: “4”, “24”; Fuse (Passenger Compartment Relay Box) No.: “3”, “4”
  8. RED-WHT (ORG) – Fuse No.: “15”, “21”, “22”
  9. RED-BLK (ORG) – Fuse No.: “23”
  10. RED (ORG) – Fuse No.: “18”, “25”
  11. RED (ORG) – Ignition Switch, Retained Accessory Power (RAP) Relay No.1
  12. RED (RED) – Brake Pump Relay
  13. RED (RED) – ABS Main Relay

Fusible Link (’86-’87)

  1. YEL/RED (ORG) – Power Module, Cooling Fan Relay (B)
  2. RED (ORG) – EFI Relay
  3. RED (ORG) – Fuse (Engine Compartment Fuse Box) No.: “2”
  4. ORG (ORG) – Engine Control Module
  5. RED (ORG) – Fuse (Passenger Compartment Relay Box) No.: “2”
  6. RED (GRY) – Ignition Switch, Fuse No.: “5”, “14”, “17”
  7. RED (ORG) – Theft Deterrent Module, Fuse No.: “4”, “24”; Fuse (Passenger Compartment Relay Box) No.: “4”
  8. RED (ORG) – Fuse No.: “16”, “25”
  9. RED-BLK (ORG) – Fuse No.: “23”; RED – Fuse (Passenger Compartment Relay Box) No.: “3”
  10. RED (ORG) – Ignition Switch, Retained Accessory Power (RAP) Relay No.1
  11. RED-WHT (ORG) – Fuse No.: “15”, “21”, “22”

Relay Location (’90-’91)

Rear Window Defogger Relay, Courtesy Lights Relay, Theft Deterrent Relay, Sound System Relay, Panel Lights Inhibit Relay, Retained Accessory Power (RAP) Relay, Turn Signal Flasher Relay, Park Lights Relay, Foglight Inhibit Relay, Electronic Level Control (ELC) Relay

cadillac seville fuse box diagram relay location 1 1990
cadillac seville fuse box diagram relay location 1 1990

Starter Enable Relay, Retained Accessory Power (RAP) Relay, Retained Accessory Power (RAP) Circuit Breaker

cadillac seville fuse box diagram relay location 2 1990
cadillac seville fuse box diagram relay location 2 1990

ABS Main Relay, ABS Pump Relay, ABS Main Fuse

cadillac seville fuse box diagram relay location 3 1990
cadillac seville fuse box diagram relay location 3 1990

Starter Interrupt Relay, Theft Deterrent Relay

cadillac seville fuse box diagram relay location 4 1990
cadillac seville fuse box diagram relay location 4 1990

Conclusion

For owners and enthusiasts of classic Cadillac Seville 1986-1991, 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.