Learn about Cadillac CT4 2020-2024 fuse box and relay’s locations, functions, and maintenance tips for optimal vehicle electrical system.
The Cadillac CT4 (2020-2024) is a luxury compact sedan that combines sporty performance with elegant design. Available in several trims, including the high-performance CT4-V, the CT4 offers a dynamic driving experience with a sleek, aerodynamic body style. Its compact yet refined profile is designed for agility and comfort, appealing to those who want luxury in a smaller form factor.
To support its advanced technology and comfort features, the CT4 relies on an efficient electrical system controlled by fuse boxes and relays. The primary fuse box is located under the hood near the engine, while an additional fuse panel is situated within the cabin, typically near the driver’s side. Relays, which manage high-power components like the ignition and cooling systems, are housed near these fuse boxes. Routine maintenance of the fuse boxes and relays is essential for the reliable operation of the CT4’s electronic systems.
MUST READ: DYI – How to Check Car Fuses?
(2020-2024) Cadillac CT4 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 CT4 2020-2024 fuse assignment
Cadillac CT4 Year of production: 2020, 2021, 2022, 2023, 2024
Location of Fuse Boxes
Engine Compartment Fuse Block:
The engine compartment fuse block is on the passenger side of the engine compartment. Lift the fuse block cover to access the fuses.
Instrument Panel Fuse Block:
The instrument panel fuse block is in the end of the driver side of the instrument panel. To access the fuses, remove the end panel by gently prying with a plastic tool near each clip, beginning at the point shown.
Rear Compartment Fuse Block:
The rear compartment fuse block is behind a cover on the driver side of the rear compartment.
Fuse Box Diagrams
2020
Engine Compartment Fuse Block
List of fuses in the Engine Compartment Fuse Block (2020)
| № | Usage |
|---|---|
| 1 | Long range radar front sensor |
| 2 | Park / Daytime running lamps |
| 3 | Exterior lighting module 4 |
| 4 | Exterior lighting module 7 |
| 5 | Headlamp level |
| 6 | – |
| 7 | Electronic brake control module |
| 8 | Washer pump |
| 9 | – |
| 10 | – |
| 11 | – |
| 12 | Horn |
| 13 | Front wiper |
| 14 | Exterior lighting module 6 |
| 15 | Exterior lighting module 1 |
| 16 | Exterior lighting module 5 |
| 17 | Exterior lighting module 3 |
| 18 | Aero shutter |
| 19 | – |
| 20 | – |
| 21 | Virtual key system / Power sounder module |
| 22 | – |
| 23 | Transmission control module |
| 24 | Active engine mount |
| 25 | – |
| 26 | Engine control module |
| 27 | Injectors / Ignition 2 |
| 28 | Charged air cooler |
| 29 | Transmission coolant pump |
| 30 | Injectors / Ignition 1 |
| 31 | Emissions 1 |
| 32 | Emissions 2 |
| 33 | Starter solenoid |
| 34 | – |
| 35 | Coolant pump |
| 36 | Starter pinion |
| 37 | AC clutch |
| 38 | – |
| 39 | – |
| 40 | – |
| 41 | – |
| 42 | Water pump |
| 43 | – |
| 44 | – |
| Relays | |
| 47 | – |
| 48 | Front wiper speed |
| 49 | Front wiper control |
| 51 | – |
| 52 | Engine control module |
| 53 | Starter solenoid |
| 54 | Starter pinion |
| 55 | – |
| 57 | AC clutch |
| 58 | – |
Instrument Panel Fuse Block
List of fuses in the Instrument Panel Fuse Block (2020)
| № | Usage |
|---|---|
| 1 | – |
| 2 | HVAC blower |
| 3 | – |
| 4 | – |
| 5 | Theft deterrent / Universal garage door opener |
| 6 | – |
| 7 | Air quality ionizer |
| 8 | Heated steering wheel |
| 9 | – |
| 10 | Electronic steering column lock 1 |
| 11 | – |
| 12 | – |
| 13 | – |
| 14 | – |
| 15 | – |
| 16 | – |
| 17 | – |
| 18 | Display / Infotainment/USB |
| 19 | Airbag / Automatic occupant sensing / Data link connection / Wireless charging module |
| 20 | Power steering column module / Electronic steering column lock 2 |
| 21 | – |
| 22 | – |
| 23 | – |
| 24 | – |
| 25 | USB |
| 26 | – |
| 27 | – |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | Headlamp level |
| 32 | – |
| 33 | Body ignition / IP ignition |
| 34 | Exhaust valve |
| 35 | Transmission control module ignition / Engine control module ignition / Shift ignition / Brake ignition |
| 36 | Shift module |
| 37 | Body control module 1 / Electronic park brake switch |
| 38 | Center stack module |
| 39 | Steering wheel controls |
| 40 | Body control module 2 |
| 41 | Body control module 3 |
| 42 | Body control module 4 |
| Circuit Breakers | |
| CB1 | Auxiliary power outlet 1 |
| CB2 | Auxiliary power outlet 2 |
| Relays | |
| 1 | Run after park / Accessory |
| 2 | Run crank |
| 3 | – |
| 4 | – |
| 5 | – |
Rear Compartment Fuse Block
List of fuses in the Rear Compartment Fuse Block (2020)
| № | Usage |
|---|---|
| 1 | Remote function actuator |
| 2 | Engine control module |
| 3 | Driver heated seat |
| 4 | Fuel tank zone module |
| 5 | – |
| 6 | – |
| 7 | – |
| 8 | – |
| 9 | – |
| 10 | Motor seat belt passenger |
| 11 | Canister vent solenoid |
| 12 | Sunroof |
| 13 | – |
| 14 | – |
| 15 | Passenger heated seat |
| 16 | – |
| 17 | Electronic suspension control |
| 18 | – |
| 19 | Motor seat belt driver |
| 20 | Rear defog |
| 21 | DC to DC transformer 2 |
| 22 | Driver power window door lock switch |
| 23 | External object calculating module / Front camera module |
| 24 | Passenger window door lock switch |
| 25 | – |
| 26 | Trailer |
| 27 | Rear drive control module |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | DC to DC transformer 1 |
| 32 | Transfer case electronic control |
| 33 | Central gateway module / Side blind zone alert |
| 34 | Video processing module |
| 35 | Hands free closure release |
| 36 | Exterior lighting module 2 |
| 37 | Passenger memory seat module |
| 38 | Trailer 2 |
| 39 | Right front / Right rear window |
| 40 | – |
| 41 | – |
| 42 | Amplifier |
| 43 | Park assist module |
| 44 | Driver memory seat module |
| 45 | OnStar |
| 46 | – |
| 47 | – |
| 48 | – |
| 49 | Trailer |
| 50 | Driver seat |
| 51 | Left front / Left rear window |
| 52 | Passenger seat |
| Relays | |
| 53 | – |
| 54 | – |
| 55 | Run |
2021
Engine Compartment Fuse Block
List of fuses in the Engine Compartment Fuse Block (2021)
| № | Usage |
|---|---|
| 1 | Long range radar front sensor |
| 2 | Park / Daytime running lamps |
| 3 | Exterior lighting module 4 |
| 4 | Exterior lighting module 7 |
| 5 | Headlamp level |
| 6 | – |
| 7 | Electronic brake control module |
| 8 | Washer pump |
| 9 | – |
| 10 | – |
| 11 | – |
| 12 | Horn |
| 13 | Front wiper |
| 14 | Exterior lighting module 6 |
| 15 | Exterior lighting module 1 |
| 16 | Exterior lighting module 5 |
| 17 | Exterior lighting module 3 |
| 18 | Aero shutter |
| 19 | – |
| 20 | – |
| 21 | Virtual key system / Power sounder module |
| 22 | Engine control module |
| 23 | Transmission control module / Transmission reverse lock out |
| 24 | Active engine mount |
| 25 | – |
| 26 | Engine control module |
| 27 | Injectors / Ignition 2 |
| 28 | Charged air cooler |
| 29 | Transmission aux oil pump / Transmission reverse lock out |
| 30 | Injectors / Ignition 1 |
| 31 | Emissions 1 |
| 32 | Emissions 2 |
| 33 | Starter solenoid |
| 34 | – |
| 35 | – |
| 36 | Starter pinion |
| 37 | AC clutch |
| 38 | – |
| 39 | – |
| 40 | – |
| 41 | – |
| 42 | Water pump |
| 43 | – |
| 44 | – |
| Relays | |
| 47 | – |
| 48 | Front wiper speed |
| 49 | Front wiper control |
| 51 | – |
| 52 | Engine control module |
| 53 | Starter solenoid |
| 54 | Starter pinion |
| 55 | – |
| 57 | AC clutch |
| 58 | – |
Instrument Panel Fuse Block
List of fuses in the Instrument Panel Fuse Block (2021)
| № | Usage |
|---|---|
| 1 | – |
| 2 | HVAC blower |
| 3 | – |
| 4 | – |
| 5 | Theft deterrent / Universal garage door opener / Overhead console / Rain sensor |
| 6 | – |
| 7 | Air quality ionizer |
| 8 | Heated steering wheel |
| 9 | – |
| 10 | Electronic steering column lock 1 |
| 11 | – |
| 12 | – |
| 13 | – |
| 14 | – |
| 15 | – |
| 16 | – |
| 17 | – |
| 18 | Display / Infotainment / USB / Multi-function control module |
| 19 | Airbag / Automatic occupant sensing / Data link connection / Wireless charging module / Virtual key module |
| 20 | Power steering column module / Electronic steering column lock 2 |
| 21 | Driver monitor system / Performance data recorder |
| 22 | – |
| 23 | – |
| 24 | – |
| 25 | USB |
| 26 | – |
| 27 | – |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | Headlamp level |
| 32 | – |
| 33 | Body ignition / IP ignition |
| 34 | Exhaust valve |
| 35 | Transmission control module ignition / Engine control module ignition / Shift ignition / Brake ignition |
| 36 | Shift module |
| 37 | Body control module 1 / Electronic park brake switch |
| 38 | Center stack module |
| 39 | Steering wheel controls |
| 40 | Body control module 2 |
| 41 | Body control module 3 |
| 42 | Body control module 4 |
| Circuit Breakers | |
| CB1 | Auxiliary power outlet 1 |
| CB2 | Auxiliary power outlet 2 |
| Relays | |
| 1 | Run after park / Accessory |
| 2 | Run crank |
| 3 | – |
| 4 | – |
| 5 | – |
Rear Compartment Fuse Block
List of fuses in the Rear Compartment Fuse Block (2021)
| № | Usage |
|---|---|
| 1 | Remote function actuator |
| 2 | – |
| 3 | Driver heated seat |
| 4 | Fuel tank zone module |
| 5 | – |
| 6 | – |
| 7 | – |
| 8 | – |
| 9 | – |
| 10 | Motor seat belt passenger |
| 11 | Canister vent solenoid |
| 12 | Sunroof |
| 13 | – |
| 14 | – |
| 15 | Passenger heated seat |
| 16 | – |
| 17 | Electronic suspension control |
| 18 | – |
| 19 | Motor seat belt driver |
| 20 | Rear defog |
| 21 | DC to DC transformer 2 |
| 22 | Driver power window / Door handle switch |
| 23 | External object calculating module / Front camera module / High definition localization / Short range radar |
| 24 | Passenger power window / Door handle switch |
| 25 | – |
| 26 | – |
| 27 | Rear drive control module |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | DC to DC transformer 1 |
| 32 | Transfer case electronic control |
| 33 | Central gateway module / Side blind zone alert |
| 34 | Video processing module |
| 35 | Hands free closure release |
| 36 | Exterior lighting module 2 |
| 37 | Passenger memory seat module |
| 38 | – |
| 39 | Right front / Right rear window |
| 40 | – |
| 41 | – |
| 42 | Amplifier |
| 43 | Park assist module |
| 44 | Driver memory seat module |
| 45 | OnStar |
| 46 | – |
| 47 | – |
| 48 | – |
| 49 | – |
| 50 | Driver seat |
| 51 | Left front / Left rear window |
| 52 | Passenger seat |
| Relays | |
| 53 | – |
| 54 | – |
| 55 | Run |
2022
Engine Compartment Fuse Block
List of fuses in the Engine Compartment Fuse Block (2022)
| № | Usage |
|---|---|
| 1 | Long Range Radar Front Sensor |
| 2 | Park/Daytime Running Lamps |
| 3 | Exterior Lighting Module 4 |
| 4 | Exterior Lighting Module 7 |
| 5 | Headlamp Level |
| 6 | – |
| 7 | Electronic Brake Control Module |
| 8 | Washer Pump |
| 9 | – |
| 10 | – |
| 11 | – |
| 12 | Horn |
| 13 | Front Wiper |
| 14 | Exterior Lighting Module 6 |
| 15 | Exterior Lighting Module 1 |
| 16 | Exterior Lighting Module 5 |
| 17 | Exterior Lighting Module 3 |
| 18 | Aero Shutter |
| 19 | – |
| 20 | – |
| 21 | Virtual Key System / Power Sounder Module |
| 22 | Engine Control Module Battery |
| 23 | Transmission Control Module |
| 24 | Active Engine Mount |
| 25 | – |
| 26 | Engine Control Module |
| 27 | Injectors / Ignition 2 |
| 28 | Charged Air Cooler |
| 29 | Transmission Aux Oil Pump / Transmission Reverse Lock Out |
| 30 | Injectors / Ignition 1 |
| 31 | Emissions 1 |
| 32 | Emissions 2 |
| 33 | Starter Solenoid |
| 34 | – |
| 35 | – |
| 36 | Starter Pinion |
| 37 | AC Clutch |
| 38 | – |
| 39 | – |
| 40 | – |
| 41 | – |
| 42 | Water Pump |
| 43 | – |
| 44 | – |
| Relays | |
| 47 | – |
| 48 | Front Wiper Speed |
| 49 | Front Wiper Control |
| 51 | – |
| 52 | Engine Control Module |
| 53 | Starter Solenoid |
| 54 | Starter Pinion |
| 55 | – |
| 57 | AC Clutch |
| 58 | – |
Instrument Panel Fuse Block
List of fuses in the Instrument Panel Fuse Block (2022)
| № | Usage |
|---|---|
| 1 | – |
| 2 | Heating, Ventilation, and Air Conditioning Blower |
| 3 | – |
| 4 | – |
| 5 | Theft Deterrent / Universal Garage Door Opener / Overhead Console / Rain Sensor |
| 6 | – |
| 7 | Air Quality Ionizer |
| 8 | Heated Steering Wheel |
| 9 | – |
| 10 | Electronic Steering Column Lock 1 |
| 11 | – |
| 12 | – |
| 13 | – |
| 14 | – |
| 15 | – |
| 16 | – |
| 17 | – |
| 18 | Display / Infotainment / USB / Multi-function Control Module |
| 19 | Sensing and Diagnostic Module / Automatic Occupant Sensing / Data Link Connection / Wireless Charging Module / Virtual Key Module |
| 20 | Power Steering Column Module / Electronic Steering Column Lock 2 |
| 21 | Driver Monitor System / Performance Data Recorder |
| 22 | – |
| 23 | – |
| 24 | – |
| 25 | USB |
| 26 | – |
| 27 | – |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | Headlamp Level |
| 32 | – |
| 33 | Body Ignition / IP Ignition |
| 34 | Exhaust Valve |
| 35 | Transmission Control Module Ignition / Engine Control Module Ignition / Shift Ignition / Brake Ignition |
| 36 | Shift Module |
| 37 | Body Control Module 1 / Electronic Park Brake Switch |
| 38 | Center Stack Module |
| 39 | Steering Wheel Controls |
| 40 | Body Control Module 2 |
| 41 | Body Control Module 3 |
| 42 | Body Control Module 4 |
| Circuit Breakers | |
| CB1 | Auxiliary Power Outlet 1 |
| CB2 | Auxiliary Power Outlet 2 |
| Relays | |
| 1 | Run After Park / Accessory |
| 2 | Run Crank |
| 3 | – |
| 4 | – |
| 5 | – |
Rear Compartment Fuse Block
List of fuses in the Rear Compartment Fuse Block (2022)
| № | Usage |
|---|---|
| 1 | Remote Function Actuator |
| 2 | – |
| 3 | Driver Heated Seat |
| 4 | Fuel Tank Zone Module |
| 5 | – |
| 6 | – |
| 7 | – |
| 8 | – |
| 9 | – |
| 10 | Motor Seat Belt Passenger |
| 11 | Canister Vent Solenoid |
| 12 | Sunroof |
| 13 | – |
| 14 | – |
| 15 | Passenger Heated Seat |
| 16 | – |
| 17 | Electronic Suspension Control |
| 18 | – |
| 19 | Motor Seat Belt Driver |
| 20 | Rear Defog |
| 21 | DC to DC Transformer 2 |
| 22 | Driver Power Window / Door Handle Switch |
| 23 | External Object Calculating Module / Front Camera Module / High Definition Localization Module / Short Range Radar |
| 24 | Passenger Power Window / Door Handle Switch |
| 25 | – |
| 26 | Amplifier (V-Series Blackwing) |
| 27 | Rear Drive Control Module |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | DC to DC Transformer 1 |
| 32 | Transfer Case Electronic Control |
| 33 | Central Gateway Module / Side Blind Zone Alert |
| 34 | Video Processing Module |
| 35 | Hands Free Closure Release |
| 36 | Exterior Lighting Module 2 |
| 37 | Passenger Memory Seat Module |
| 38 | – |
| 39 | Right Front / Right Rear Window |
| 40 | – |
| 41 | – |
| 42 | Amplifier |
| 43 | Park Assist Module |
| 44 | Driver Memory Seat Module |
| 45 | OnStar |
| 46 | – |
| 47 | – |
| 48 | – |
| 49 | – |
| 50 | Driver Seat |
| 51 | Left Front / Left Rear Window |
| 52 | Passenger Seat |
| Relays | |
| 53 | – |
| 54 | – |
| 55 | Run |
2023
Engine Compartment Fuse Block
List of fuses in the Engine Compartment Fuse Block (2023)
| № | Usage |
|---|---|
| 1 | Long Range Radar Front Sensor |
| 2 | Park / Daytime Running Lamps |
| 3 | Exterior Lighting Module 4 |
| 4 | Exterior Lighting Module 7 |
| 5 | Headlamp Level |
| 6 | – |
| 7 | Electronic Brake Control Module |
| 8 | Washer Pump |
| 9 | – |
| 10 | – |
| 11 | – |
| 12 | Horn |
| 13 | Front Wiper |
| 14 | Exterior Lighting Module 6 |
| 15 | Exterior Lighting Module 1 |
| 16 | Exterior Lighting Module 5 |
| 17 | Exterior Lighting Module 3 |
| 18 | Aero Shutter |
| 19 | – |
| 20 | – |
| 21 | Virtual Key System / Power Sounder Module |
| 22 | Engine Control Module Battery |
| 23 | Transmission Control Module |
| 24 | Active Engine Mount |
| 25 | – |
| 26 | Engine Control Module |
| 27 | Injectors / lgnition 2 |
| 28 | Charged Air Cooler / Not Used |
| 29 | Transmission Aux Oil Pump / Transmission Reverse Lock Out |
| 30 | Injectors / lgnition 1 |
| 31 | Emissions 1 |
| 32 | Emissions 2 |
| 33 | Starter Solenoid |
| 34 | – |
| 35 | – |
| 36 | Starter Pinion / Not Used |
| 37 | AC Clutch |
| 38 | – |
| 39 | – |
| 40 | – |
| 41 | – |
| 42 | Water Pump / Not Used |
| 43 | – |
| 44 | – |
| Relays | |
| 47 | – |
| 48 | Front Wiper Speed / Not Used |
| 49 | Front Wiper Control |
| 51 | – |
| 52 | Engine Control Module |
| 53 | Starter Solenoid |
| 54 | Starter Pinion / Not Used |
| 55 | – |
| 57 | AC Clutch |
| 58 | – |
Instrument Panel Fuse Block
List of fuses in the Instrument Panel Fuse Block (2023)
| № | Usage |
|---|---|
| 1 | – |
| 2 | Heating, Ventilation, and Air Conditioning Blower |
| 3 | – |
| 4 | – |
| 5 | Theft Deterrent / Universal Garage Door Opener / Overhead Console / Rain Sensor |
| 6 | – |
| 7 | Air Quality Ionizer |
| 8 | Heated Steering Wheel |
| 9 | – |
| 10 | Electronic Steering Column Lock 1 |
| 11 | – |
| 12 | – |
| 13 | – |
| 14 | – |
| 15 | – |
| 16 | – |
| 17 | – |
| 18 | Display / lnfotainment / USB / Multi-function Control Module |
| 19 | Sensing and Diagnostic Module / Automatic Occupant Sensing / Data Link Connection / Wireless Charging Module / Virtual Key Module |
| 20 | Power Steering Column Module / Electronic Steering Column Lock 2 |
| 21 | Driver Monitor System / Performance Data Recorder |
| 22 | – |
| 23 | – |
| 24 | – |
| 25 | USB |
| 26 | – |
| 27 | – |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | Headlamp Level |
| 32 | – |
| 33 | Body Ignition / IP Ignition |
| 34 | Exhaust Valve |
| 35 | Transmission Control Module Ignition / Engine Control Module Ignition / Shift Ignition / Brake Ignition |
| 36 | Shift Module |
| 37 | Body Control Module 1 / Electronic Park Brake Switch |
| 38 | Center Stack Module |
| 39 | Steering Wheel Controls |
| 40 | Body Control Module 2 |
| 41 | Body Control Module 3 |
| 42 | Body Control Module 4 |
| Circuit Breakers | |
| CB1 | Auxiliary Power Outlet 1 |
| CB2 | Auxiliary Power Outlet 2 |
| Relays | |
| 1 | Run After Park / Accessory |
| 2 | Run Crank |
| 3 | – |
| 4 | – |
| 5 | – |
Rear Compartment Fuse Block
List of fuses in the Rear Compartment Fuse Block (2023)
| № | Usage |
|---|---|
| 1 | Remote Function Actuator |
| 2 | – |
| 3 | Driver Heated Seat |
| 4 | Fuel Tank Zone Module |
| 5 | – |
| 6 | – |
| 7 | – |
| 8 | – |
| 9 | – |
| 10 | Motor Seat Belt Passenger |
| 11 | Canister Vent Solenoid |
| 12 | Sunroof |
| 13 | – |
| 14 | – |
| 15 | Passenger Heated Seat |
| 16 | – |
| 17 | Electronic Suspension Control |
| 18 | – |
| 19 | Motor Seat Belt Driver |
| 20 | Rear Defog |
| 21 | DC to DC Transformer 2 |
| 22 | Driver Power Window / Door Handle Switch |
| 23 | External Object Calculating Module / Front Camera Module / High Definition Localization Module / Short Range Radar |
| 24 | Passenger Power Window / Door Handle Switch |
| 25 | – |
| 26 | Amplifier (V-Series Blackwing) |
| 27 | Rear Drive Control Module |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | DC to DC Transformer! |
| 32 | Transfer Case Electronic Control |
| 33 | Central Gateway Module / Side Blind Zone Alert |
| 34 | Video Processing Module |
| 35 | Hands Free Closure Release |
| 36 | Exterior Lighting Module 2 |
| 37 | Passenger Memory Seat Module |
| 38 | – |
| 39 | Right Front / Right Rear Window |
| 40 | – |
| 41 | – |
| 42 | Amplifier |
| 43 | Park Assist Module |
| 44 | Driver Memory Seat Module |
| 45 | OnStar |
| 46 | – |
| 47 | – |
| 48 | – |
| 49 | – |
| 50 | Driver Seat |
| 51 | Left Front / Left Rear Window |
| 52 | Passenger Seat |
| Relays | |
| 53 | – |
| 54 | – |
| 55 | Run |
2024
Engine Compartment Fuse Block
List of fuses in the Engine Compartment Fuse Block (2024)
| № | Usage |
|---|---|
| 1 | Long Range Radar Front Sensor |
| 2 | Park / Daytime Running Lamps |
| 3 | Exterior Lighting Module 4 |
| 4 | Exterior Lighting Module 7 |
| 5 | Headlamp Level |
| 6 | – |
| 7 | Electronic Brake Control Module |
| 8 | Washer Pump |
| 9 | – |
| 10 | – |
| 11 | – |
| 12 | Horn |
| 13 | Front Wiper |
| 14 | Exterior Lighting Module 6 |
| 15 | Exterior Lighting Module 1 |
| 16 | Exterior Lighting Module 5 |
| 17 | Exterior Lighting Module 3 |
| 18 | Aero Shutter |
| 19 | – |
| 20 | – |
| 21 | Virtual Key System / Power Sounder Module |
| 22 | Engine Control Module Battery |
| 23 | Transmission Control Module |
| 24 | Active Engine Mount |
| 25 | – |
| 26 | Engine Control Module |
| 27 | Injectors / lgnition 2 |
| 28 | Charged Air Cooler / Not Used |
| 29 | Transmission Aux Oil Pump / Transmission Reverse Lock Out |
| 30 | Injectors / lgnition 1 |
| 31 | Emissions 1 |
| 32 | Emissions 2 |
| 33 | Starter Solenoid |
| 34 | – |
| 35 | – |
| 36 | Starter Pinion / Not Used |
| 37 | AC Clutch |
| 38 | – |
| 39 | – |
| 40 | – |
| 41 | – |
| 42 | Water Pump / Not Used |
| 43 | – |
| 44 | – |
| Relays | |
| 47 | – |
| 48 | Front Wiper Speed / Not Used |
| 49 | Front Wiper Control |
| 51 | – |
| 52 | Engine Control Module |
| 53 | Starter Solenoid |
| 54 | Starter Pinion / Not Used |
| 55 | – |
| 57 | AC Clutch |
| 58 | – |
Instrument Panel Fuse Block
List of fuses in the Instrument Panel Fuse Block (2024)
| № | Usage |
|---|---|
| 1 | – |
| 2 | Heating, Ventilation, and Air Conditioning Blower |
| 3 | – |
| 4 | – |
| 5 | Theft Deterrent / Universal Garage Door Opener / Overhead Console / Rain Sensor |
| 6 | – |
| 7 | Air Quality Ionizer |
| 8 | Heated Steering Wheel |
| 9 | – |
| 10 | Electronic Steering Column Lock 1 |
| 11 | – |
| 12 | – |
| 13 | – |
| 14 | – |
| 15 | – |
| 16 | – |
| 17 | – |
| 18 | Display / lnfotainment / USB / Multi-function Control Module |
| 19 | Sensing and Diagnostic Module / Automatic Occupant Sensing / Data Link Connection / Wireless Charging Module / Virtual Key Module |
| 20 | Power Steering Column Module / Electronic Steering Column Lock 2 |
| 21 | Driver Monitor System / Performance Data Recorder |
| 22 | – |
| 23 | – |
| 24 | – |
| 25 | USB |
| 26 | – |
| 27 | – |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | Headlamp Level / Spare |
| 32 | – |
| 33 | Body Ignition / IP Ignition |
| 34 | Exhaust Valve |
| 35 | Transmission Control Module Ignition / Engine Control Module Ignition / Shift Ignition / Brake Ignition |
| 36 | Shift Module |
| 37 | Body Control Module 1 / Electronic Park Brake Switch |
| 38 | Center Stack Module |
| 39 | Steering Wheel Controls |
| 40 | Body Control Module 2 |
| 41 | Body Control Module 3 |
| 42 | Body Control Module 4 |
| Circuit Breakers | |
| CB1 | Auxiliary Power Outlet 1 |
| CB2 | Auxiliary Power Outlet 2 |
| Relays | |
| 1 | Run After Park / Accessory |
| 2 | Run Crank |
| 3 | – |
| 4 | – |
| 5 | – |
Rear Compartment Fuse Block
List of fuses in the Rear Compartment Fuse Block (2024)
| № | Usage |
|---|---|
| 1 | Remote Function Actuator |
| 2 | – |
| 3 | Driver Heated Seat |
| 4 | Fuel Tank Zone Module |
| 5 | – |
| 6 | – |
| 7 | – |
| 8 | – |
| 9 | – |
| 10 | Motor Seat Belt Passenger |
| 11 | Canister Vent Solenoid |
| 12 | Sunroof |
| 13 | – |
| 14 | – |
| 15 | Passenger Heated Seat |
| 16 | – |
| 17 | Electronic Suspension Control |
| 18 | – |
| 19 | Motor Seat Belt Driver |
| 20 | Rear Defog |
| 21 | DC to DC Transformer 2 |
| 22 | Driver Power Window / Door Handle Switch |
| 23 | External Object Calculating Module / Front Camera Module / High Definition Localization Module / Short Range Radar |
| 24 | Passenger Power Window / Door Handle Switch |
| 25 | – |
| 26 | Amplifier (V-Series Blackwing) |
| 27 | Rear Drive Control Module |
| 28 | – |
| 29 | – |
| 30 | – |
| 31 | DC to DC Transformer 1 |
| 32 | Transfer Case Electronic Control |
| 33 | Central Gateway Module / Side Blind Zone Alert |
| 34 | Video Processing Module |
| 35 | Hands Free Closure Release |
| 36 | Exterior Lighting Module 2 |
| 37 | Passenger Memory Seat Module |
| 38 | – |
| 39 | Right Front / Right Rear Window |
| 40 | – |
| 41 | – |
| 42 | Amplifier |
| 43 | Park Assist Module |
| 44 | Driver Memory Seat Module |
| 45 | OnStar |
| 46 | – |
| 47 | – |
| 48 | – |
| 49 | – |
| 50 | Driver Seat |
| 51 | Left Front / Left Rear Window |
| 52 | Passenger Seat |
| Relays | |
| 53 | – |
| 54 | – |
| 55 | Run |
Conclusion
The 2020-2024 Cadillac CT4 offers luxury and performance in a compact form, supported by a well-structured electrical system. Maintaining the fuse boxes and relays is vital for dependable functionality.
