Fuses and relays Buick Roadmaster (4B; 1994-1996)

This article provides detailed fuse box diagrams for the Buick Roadmaster (Series 4B; 9th generation), covering the 1994, 1995, and 1996 model years.

Fuse #28 in the instrument panel fuse block protects the cigarette lighter circuit.

Instrument Panel Fuse Block

The fuse block is located on the driver's side of the instrument panel.

To access the fuses, remove the plastic cover.

Diagram
No.	Description
Circuit Breakers
CB1	Not Used (1994)
	Power Antenna Relay, Power Seats (1995–1996)
CB2	Master Power Window Switch Power Window Lockout Switch and Control Module
CB3	Door Lock Relay (1994) Left and Right Recline and Lumbar Switches Driver and Passenger Power Seat Switches
CB4	Rear Window Defogger Switch and Relay
CB5	Not Used
Fuses
1–5	Not Used
6	Turn Signal Flasher, Park/Neutral Position (PNP) Switch (1994)
	Not Used (1995–1996)
7	Electronic Brake Control Module (EBCM) (1994)
	Not Used (1995–1996)
8	Rear Window Wiper
9	Radio
10	Windshield Wiper/Washer Switch
11	Rear Defogger Relay, Supplemental Inflatable Restraint (SIR) System (1995–1996) Rear Compartment Lid Release Switch (1994) Sensing and Diagnostic Module (SDM) (1994) Headlamp Switch, Instrument Panel (I/P) Cluster, Rear Defogger Switch
12	Automatic Level Control (ALC) Sensor, Ignition Switch (1994)
	Turn Signal Flasher, Back-Up Lamp/Park Neutral Position (PNP) Switch, Brake Transmission Shift Interlock (BTSI) (1995–1996)
13	Inside Rearview Mirror, Warning Alarm, Cruise Control Release Switch (1994–1995), Stoplamp Switch (1996), Automatic Headlamp Control Module, Daytime Running Lamps (DRL) Control Module, Remote Keyless Entry (RKE) Receiver, Automatic Level Control (ALC) Sensor
14	Theft-Deterrent Module (TDM)
15	Airbag Module
16	Cruise Control System, Cruise Control Switch/Release Switch
17	Low Blower Motor Relay, Heater and A/C Control Head
18	Electronic Variable Orifice (EVO) Steering Control Module, Heated Seat Controls (1995–1996)
19	Not Used
20	Electric Actuator, Vacuum Electric Solenoid, Heater and A/C Control Head, Instrument Cluster, Daytime Running Lamps (DRL) (1995–1996)
21–23	Not Used
24	Airbag Module / Sensing and Diagnostic Module (SDM), Theft-Deterrent Relay
25	Not Used
26	Radio Power Antenna Relay (1994)
	Not Used (1995–1996)
27	Automatic Level Control (ALC) Sensor, Rear Compartment Courtesy Lamp, Mercury Switch
28	Cigarette Lighter Data Link Connector (DLC) (1996)
29	Remote Keyless Entry (RKE) Receiver, Rear Compartment Lid Release Switch, Liftgate Wiper Latch Switch, Liftglass Release Switch, Liftglass Release Relay, Rear Compartment Release Relay
30	Radio
31	Headlamp Switch and Automatic Control Module, Daytime Running Lamps (DRL) Control Module
32	Horn Relay
33	Warning Alarm, Instrument Panel (I/P) Compartment Lamp, I/P Cluster, Heater and A/C Control Head
34	Theft-Deterrent Module (TDM)
35	Courtesy Lamp Relay, Front Door Lock Switches and Courtesy Lamps, Rear Door Courtesy Lamps, Power Outside Rearview Mirror Switch, Inside Rearview Mirror, Sunshade, Illuminated Vanity Mirrors, I/P Door Lamps, Roof Rail Courtesy Lamps
36	Rear Window Wiper Motor, Rear Compartment Lid Pull-Down Actuator
37	Stoplamp Switch, Hazard Warning Flasher
38	Not Used (1994)
	Blower Motor Control Module (1995–1996)
39	Not Used (1994)
	Power Door Lock Relay (1995–1996)
40	Blower Motor Control Module (1994)
	Heated Seat Controls (1995–1996)
41	Turn Signal Switch, Sidemarker Lamps, Park/Turn Signal Lamps
42	Radio, Heater and A/C Control Head, Headlamp Switch, Instrument Cluster, Headlamp and Instrument Panel (I/P) Dimmer Switch, I/P Dimming Module, Interior Lamps (1994)
	Radio, Heater and A/C Control Head, Headlamp Switch, Instrument Cluster (1995–1996)
43	Opera and License Plate Lamps, Marker Lamps, Inboard Taillamps, Outboard Park/Turn/Stoplamps, Inboard Park/Turn/Stoplamps
44	Heated Power Mirrors
45	Not Used

Underhood Fuse Block

The fuse block is located on the right side of the engine compartment, behind the plastic cover.

Accessing the underhood fuse block.

Diagram
No.	Description
Relays
R1	Fuel Pump Relay
R2	A/C Compressor Clutch Relay
R3	Secondary Air Injection (AIR) Pump Relay
R4	Cooling Fan 1 (Primary) Relay
R5	Cooling Fan 2 (Secondary) Relay
Fuses
1	Automatic Level Control (ALC) Air Compressor
2	Fuel Pump Switch/Relay Engine Oil Pressure Sensor (1994–1995) Powertrain Control Module (PCM)
3	Underhood Lamp, Secondary Air Injection (AIR) Pump Relay
4	Mass Airflow (MAF) Sensor Evaporative Emission (EVAP) Canister Purge Solenoid Secondary Air Injection (AIR) Pump Relay Exhaust Gas Recirculation (EGR) Solenoid Automatic Transmission Heated Oxygen Sensors (HO2S)
5	Powertrain Control Module (PCM), Electronic Brake Control Module (EBCM), Ignition Coil
6	Fuel Injectors (Cylinders 1, 4, 6, 7)
7	Cooling Fan 1 Relay, A/C Compressor Clutch Relay
8	Generator, Cooling Fan 2 Relay
9	Fuel Injectors (Cylinders 2, 3, 5, 8)