Engine compartment (CTS Coupe and Sedan)
The underhood fuse block is located on the passenger side of the engine compartment.
| Mini-Fuses | Usage |
| 11 | Not Used |
| 19 | Antilock Braking System (ABS) |
| 22 | Display |
| 23 | Not Used |
| 24 | Body Control Module 1 |
| 25 | Automatic Forward Lighting System (HID Only) |
| 26 | Body Control Module 5 |
| 27 | Body Control Module 4 |
| 28 | Navigation Motor |
| 29 | All-Wheel Drive |
| 30 | Transmission Control Module Battery |
| 31 | Horn |
| 33 | Left Low‐Beam Headlamp (Domestic Non‐HID Only) |
| 34 | Pedestrian Protection System (Export Only) |
| 35 | Body Control Module 3 |
| 36 | Body Control Module 2 |
| 38 | Headlamp Washer (HID Only) |
| 40 | Right Low‐Beam Headlamp (Domestic Non‐HID Only) |
| 41 | Air Conditioning Compressor Clutch |
| 43 | Low‐Beam Daytime Running Lamps (non‐HID), Left Daytime Running Lamps (HID), Left Trailer Turn Signal (Export Only) |
| 46 | Left High‐Beam Headlamp |
| 47 | Right High‐Beam Headlamp |
| 50 | Right Daytime Running Lamp, Windshield Washer Pump |
| 51 | Airbag System Ignition Switch |
| 52 | Engine Control Module Ignition, Transmission Control Module Ignition |
| 54 | Power Moding (Immobilizer Module, Ignition Switch) |
| 55 | Not Used |
| 56 | Windshield Wipers |
| 57 | Right Low‐Beam (HID Only) |
| 58 | Daytime Running Lamps (non‐HID), Left Low‐Beam (HID Only) |
| 59 | Right Daytime Running Lamp (HID Only), Right Trailer Turn Signal (Export Only) |
| 60 | Instrument Panel Auxiliary Power Outlet |
| 61 | Air Quality Sensor, Inside Rear View Mirror, Rear Camera |
| 62 | Ignition |
| 64 | Steering Wheel Illumination |
| 65 | Front Fog Lamps (HID Only) |
| 69 | Body Control Module 6, Body Control Module 7 |
| 70 | Emissions 1 |
| 71 | Even Ignition Coils |
| 72 | Engine Control Module |
| 73 | Emissions 2 |
| 74 | Odd Ignition Coils |
| 75 | Transmission Output Speed Sensor, Brake Vacuum Relay |
| 76 | Spare |
| 77 | Spare |
| 78 | Spare |
| 79 | Spare |
| 80 | Spare |
| 81 | Spare |
| J-Case Fuses | Usage |
| 6 | Cooling Fan 2 |
| 7 | Cooling Fan 1 |
| 8 | Starter |
| 9 | Brake Vacuum Pump |
| 10 | Antilock Brake System Motor |
| 13 | Not Used |
| 14 | Electric Parking Brake |
| 15 | Not Used |
| 16 | Not Used |
| 17 | Blower Motor |
| 18 | Rear Window Defogger |
| 37 | Not Used |
| Relays | Usage |
| 1 | Cooling Fan 2 |
| 2 | Cooling Fan 1 |
| 3 | Starter |
| 4 | Rear Window Defogger |
| 5 | Instrument Panel Auxiliary Power Outlet |
| 12 | Horn |
| 20 | Headlamp Washer (HID Only) |
| 21 | Cooling Fan (Series/Parallel) |
| 32 | Air Conditioning Compressor Clutch |
| 39 | Windshield Washer Pump |
| 42 | Right Daytime Running Lamp, Trailer Turn Signal |
| 44 | Low‐Beam (non‐HID), Left Daytime Running Lamps (HID), Left Trailer Turn Signal (Export Only) |
| 45 | Front Fog Lamps (HID Only) |
| 48 | High‐Beam Headlamps |
| 49 | Daytime Running Lamps (Non‐HID), Low‐Beam Headlamps (HID) |
| 53 | Not Used |
| 63 | Main Ignition |
| 66 | Windshield Wipers |
| 67 | Powertrain |
| 68 | Windshield Wipers High Speed |
Engine compartment (CTS V Coupe and Sedan)
The underhood fuse block is located on the passenger side of the engine compartment.
| Mini-Fuses | Usage |
| 11 | Not used |
| 19 | Antilock Braking System (ABS) |
| 22 | Display |
| 23 | Sunroof |
| 24 | Body Control Module 1 |
| 25 | Automatic Forward Lighting System (HID Only) |
| 26 | Body Control Module 5 |
| 27 | Body Control Module 4 |
| 28 | Navigation Motor |
| 29 | Not used |
| 30 | Transmission Control Module Battery |
| 31 | Horn |
| 33 | Not Used |
| 34 | Pedestrian Protection System (Export Only) |
| 35 | Body Control Module 3 |
| 36 | Body Control Module 2 |
| 38 | Headlamp Washer (HID Only) |
| 40 | Not Used |
| 41 | Air Conditioning Compressor Clutch |
| 43 | Left Daytime Running Lamps (HID) |
| 46 | Left High‐Beam Headlamp |
| 47 | Right High‐Beam Headlamp |
| 50 | Right Daytime Running Lamp, Windshield Washer Pump |
| 51 | Airbag System Ignition Switch |
| 52 | Engine Control Module Ignition, Transmission Control Module Ignition |
| 54 | Power Moding (Immobilizer Module, Ignition Switch) |
| 55 | Intercooler Pump |
| 56 | Windshield Wipers |
| 57 | Right Low‐Beam (HID Only) |
| 58 | Left Low‐Beam (HID Only) |
| 59 | Right Daytime Running Lamp (HID Only) |
| 60 | Instrument Panel Auxiliary Power Outlet |
| 61 | Air Quality Sensor, Inside Rear View Mirror, Rear Camera |
| 62 | Ignition |
| 64 | Steering Wheel Illumination |
| 65 | Front Fog Lamps (HID Only) |
| 69 | Body Control Module 6, Body Control Module 7 |
| 70 | Emissions 1 |
| 71 | Even Ignition Coils |
| 72 | Odd Ignition Coils |
| 73 | Emissions 2 |
| 74 | Engine Control Module |
| 75 | Not Used |
| 76 | Spare |
| 77 | Spare |
| 78 | Spare |
| 79 | Spare |
| 80 | Spare |
| 81 | Spare |
| J-Case Fuses | Usage |
| 6 | Cooling Fan 2 |
| 7 | Cooling Fan 1 |
| 8 | Starter |
| 9 | Not Used |
| 10 | Antilock Brake System Motor |
| 13 | Not Used |
| 14 | Electric Parking Brake |
| 15 | Not Used |
| 16 | Not Used |
| 17 | Blower Motor |
| 18 | Rear Window Defogger |
| 37 | Magnetic Ride/Suspension Control |
| Relays | Usage |
| 1 | Cooling Fan 2 |
| 2 | Cooling Fan 1 |
| 3 | Starter |
| 4 | Rear Window Defogger |
| 5 | Instrument Panel Auxiliary Power Outlet |
| 12 | Horn |
| 20 | Headlamp Washer (HID Only) |
| 21 | Cooling Fan (Series/Parallel) |
| 32 | Air Conditioning Compressor Clutch |
| 39 | Windshield Washer Pump |
| 42 | Right Daytime Running Lamp |
| 44 | Left Daytime Running Lamp (HID) |
| 45 | Front Fog Lamps (HID Only) |
| 48 | High‐Beam Headlamps |
| 49 | Low‐Beam Headlamps (HID) |
| 53 | Not Used |
| 63 | Main Ignition |
| 66 | Windshield Wipers |
| 67 | Powertrain |
| 68 | Windshield Wipers High Speed |
Engine Compartment (CTS Wagon)
The underhood fuse block is located on the passenger side of the engine compartment.
| Mini-Fuses | Usage |
| 11 | Not Used |
| 19 | Antilock Braking System (ABS) |
| 22 | Display |
| 23 | Not Used |
| 24 | Body Control Module 1 |
| 25 | Automatic Forward Lighting System (HID Only) |
| 26 | Body Control Module 5 |
| 27 | Body Control Module 4 |
| 28 | Navigation Motor |
| 29 | All-Wheel Drive |
| 30 | Transmission Control Module Battery |
| 31 | Horn |
| 33 | Left Low‐Beam Headlamp (Domestic Non‐HID Only) |
| 34 | Pedestrian Protection System (Export Only) |
| 35 | Body Control Module 3 |
| 36 | Body Control Module 2 |
| 38 | Headlamp Washer (HID Only) |
| 40 | Right Low‐Beam Headlamp (Domestic Non‐HID Only) |
| 41 | Air Conditioning Compressor Clutch |
| 43 | Low‐Beam Daytime Running Lamps (non‐HID), Left Daytime Running Lamps (HID), Left Trailer Turn Signal (Export Only) |
| 46 | Left High‐Beam Headlamp |
| 47 | Right High‐Beam Headlamp |
| 50 | Right Daytime Running Lamp |
| 51 | Airbag System Ignition Switch |
| 52 | Engine Control Module Ignition, Transmission Control Module Ignition |
| 54 | Power Moding (Immobilizer Module, Ignition Switch) |
| 55 | Not Used |
| 56 | Windshield Wipers |
| 57 | Right Low‐Beam (HID Only) |
| 58 | Daytime Running Lamps (non‐HID), Left Low‐Beam (HID Only) |
| 59 | Right Daytime Running Lamp (HID Only), Right Trailer Turn Signal (Export Only) |
| 60 | Instrument Panel Auxiliary Power Outlet |
| 61 | Air Quality Sensor, Inside Rear View Mirror, Rear Camera |
| 62 | Ignition |
| 64 | Steering Wheel Illumination |
| 65 | Front Fog Lamps (HID Only) |
| 69 | Body Control Module 6, Body Control Module 7 |
| 70 | Emissions 1 |
| 71 | Even Ignition Coils |
| 72 | Engine Control Module |
| 73 | Emissions 2 |
| 74 | Odd Ignition Coils |
| 75 | Transmission Output Speed Sensor, Brake Vacuum Relay |
| 76 | Spare |
| 77 | Spare |
| 78 | Spare |
| 79 | Spare |
| 80 | Spare |
| 81 | Spare |
| J-Case Fuses | Usage |
| 6 | Cooling Fan 2 |
| 7 | Cooling Fan 1 |
| 8 | Starter |
| 9 | Brake Vacuum Pump |
| 10 | Antilock Brake System Motor |
| 13 | Not Used |
| 14 | Electric Parking Brake |
| 15 | Not Used |
| 16 | Not Used |
| 17 | Blower Motor |
| 18 | Transmission Control Module Battery |
| 37 | Trailer (Export Only) |
| Relays | Usage |
| 1 | Cooling Fan 2 |
| 2 | Cooling Fan 1 |
| 3 | Starter |
| 4 | Rear Window Defogger |
| 5 | Instrument Panel Auxiliary Power Outlet |
| 12 | Horn |
| 20 | Headlamp Washer (HID Only) |
| 21 | Cooling Fan (Series/Parallel) |
| 32 | Air Conditioning Compressor Clutch |
| 39 | Not used |
| 42 | Right Daytime Running Lamp, Trailer Turn Signal |
| 44 | Low‐Beam (non‐HID), Left Daytime Running Lamps (HID), Left Trailer Turn Signal (Export Only) |
| 45 | Front Fog Lamps (HID Only) |
| 48 | High‐Beam Headlamps |
| 49 | Daytime Running Lamps (Non‐HID), Low‐Beam Headlamps (HID) |
| 53 | Not Used |
| 63 | Main Ignition |
| 66 | Windshield Wipers |
| 67 | Powertrain |
| 68 | Windshield Wipers High Speed |
Engine Compartment (CTS V Wagon)
The underhood fuse block is located on the passenger side of the engine compartment.
| Mini-Fuses | Usage |
| 11 | Not Used |
| 19 | Antilock Braking System (ABS) |
| 22 | Display |
| 23 | Sunroof |
| 24 | Body Control Module 1 |
| 25 | Automatic Forward Lighting System (HID Only) |
| 26 | Body Control Module 5 |
| 27 | Body Control Module 4 |
| 28 | Navigation Motor |
| 29 | Not used |
| 30 | Transmission Control Module Battery |
| 31 | Horn |
| 33 | Not used |
| 34 | Pedestrian Protection System (Export Only) |
| 35 | Body Control Module 3 |
| 36 | Body Control Module 2 |
| 38 | Headlamp Washer (HID Only) |
| 40 | Not used |
| 41 | Air Conditioning Compressor Clutch |
| 43 | Left Daytime Running Lamps (HID) |
| 46 | Left High‐Beam Headlamp |
| 47 | Right High‐Beam Headlamp |
| 50 | Right Daytime Running Lamp |
| 51 | Airbag System Ignition Switch |
| 52 | Engine Control Module Ignition, Transmission Control Module Ignition |
| 54 | Power Moding (Immobilizer Module, Ignition Switch) |
| 55 | Intercooler Pump |
| 56 | Windshield Wipers |
| 57 | Right Low‐Beam (HID Only) |
| 58 | Left Low‐Beam (HID Only) |
| 59 | Right Daytime Running Lamp (HID Only) |
| 60 | Instrument Panel Auxiliary Power Outlet |
| 61 | Air Quality Sensor, Inside Rear View Mirror, Rear Camera |
| 62 | Ignition |
| 64 | Steering Wheel Illumination |
| 65 | Front Fog Lamps (HID Only) |
| 69 | Body Control Module 6, Body Control Module 7 |
| 70 | Emissions 1 |
| 71 | Even Ignition Coils |
| 72 | Odd Ignition Coils |
| 73 | Emissions 2 |
| 74 | Engine Control Module |
| 75 | Not used |
| 76 | Spare |
| 77 | Spare |
| 78 | Spare |
| 79 | Spare |
| 80 | Spare |
| 81 | Spare |
| J-Case Fuses | Usage |
| 6 | Cooling Fan 2 |
| 7 | Cooling Fan 1 |
| 8 | Starter |
| 9 | Not used |
| 10 | Antilock Brake System Motor |
| 13 | Not Used |
| 14 | Electric Parking Brake |
| 15 | Not Used |
| 16 | Not Used |
| 17 | Blower Motor |
| 18 | Rear Window Defogger |
| 37 | Magnetic Ride/ Suspension Control |
| Relays | Usage |
| 1 | Cooling Fan 2 |
| 2 | Cooling Fan 1 |
| 3 | Starter |
| 4 | Rear Window Defogger |
| 5 | Instrument Panel Auxiliary Power Outlet |
| 12 | Horn |
| 20 | Headlamp Washer (HID Only) |
| 21 | Cooling Fan (Series/Parallel) |
| 32 | Air Conditioning Compressor Clutch |
| 39 | Not used |
| 42 | Right Daytime Running Lamp |
| 44 | Left Daytime Running Lamps (HID) |
| 45 | Front Fog Lamps (HID Only) |
| 48 | High‐Beam Headlamps |
| 49 | Low‐Beam Headlamps (HID) |
| 53 | Not Used |
| 63 | Main Ignition |
| 66 | Windshield Wipers |
| 67 | Powertrain |
| 68 | Windshield Wipers High Speed |
Rear Compartment Fuse Block (CTS Coupe and Sedan)
The rear compartment fuse block is located on top of the battery, on the right side of the trunk. The battery access door must be removed to access the fuse block.
| Relays | Usage |
| 5 | Stop Lamps (Export Only) |
| 6 | Door Lock |
| 7 | Door Unlock |
| 8 | Fuel Door Unlock (Export Only) |
| 9 | Right Position Lamp (Export Only) |
| 10 | Console/Auxiliary Power Outlet |
| 11 | Trunk Release |
| 12 | Side Marker Lamps |
| 13 | Left Position Lamps |
| Mini-Fuses | Usage |
| 14 | Right Position Lamp |
| 15 | Left Position Lamp |
| 16 | Door Lock |
| 17 | Console/Auxiliary Power Outlet |
| 18 | Rear Fog/Export Body Control Module (Export Only) |
| 19 | Trunk Release |
| 20 | Easy Entry Seats (Coupe Only) |
| 21 | Sunroof |
| 22 | Right Position Lamp (Export Only) |
| 23 | Regulated Voltage Control Sensor |
| 24 | Audio System (Radio) |
| 25 | Airbag System |
| 26 | Remote Keyless Entry/PASS‐Key® Theft Deterrent Module |
| 27 | Audio Speakers/Subwoofer |
| 28 | OnStar® System |
| 29 | Engine Control Module |
| 30 | Canister Vent |
| 31 | Fuel Pump |
| 33 | Stop Lamps (Export Only) |
| 34 | Theft Deterrent System/Universal Garage Door Opener |
| 35 | Memory Seat Module |
| 36 | Passenger Door Module |
| 38 | Not Used |
| 39 | Amplifier |
| Circuit Breakers | Usage |
| 1 | Driver Power Seat Switch |
| 2 | Passenger Power Seat Switch |
| 3 | Power Windows |
| 4 | Power Steering Column |
| 32 | Left Rear Window Switch |
| 37 | Right Rear Window Switch |
Rear Compartment Fuse Block (CTS-V Coupe and Sedan)
The rear compartment fuse block is located on top of the battery, on the right side of the trunk. The battery access door must be removed to access the fuse block.
| Relays | Usage |
| 5 | Stop Lamps (Export Only) |
| 6 | Door Lock |
| 7 | Door Unlock |
| 8 | Fuel Door Unlock (Export Only) |
| 9 | Right Position Lamp (Export Only) |
| 10 | Console/Auxiliary Power Outlet |
| 11 | Trunk Release |
| 12 | Side Marker Lamps |
| 13 | Left Position Lamps |
| Mini-Fuses | Usage |
| 14 | Right Position Lamp |
| 15 | Left Position Lamp |
| 16 | Door Lock |
| 17 | Console/Auxiliary Power Outlet |
| 18 | Rear Fog/Export Body Control Module (Export Only) |
| 19 | Trunk Release |
| 20 | Easy Entry Seats (Coupe Only) |
| 21 | Fuel Pump |
| 22 | Right Position Lamp (Export Only) |
| 23 | Regulated Voltage Control Sensor |
| 24 | Audio System (Radio) |
| 25 | Airbag System |
| 26 | Remote Keyless Entry/PASS‐Key® Theft Deterrent Module |
| 27 | Audio Speakers/Subwoofer |
| 28 | OnStar® System |
| 29 | Engine Control Module |
| 30 | Canister Vent |
| 31 | Rear Differential Cooling Pump |
| 33 | Stop Lamps (Export Only) |
| 34 | Theft Deterrent System/Universal Garage Door Opener |
| 35 | Memory Seat Module |
| 36 | Passenger Door Module |
| 38 | Not Used |
| 39 | Amplifier |
| Circuit Breakers | Usage |
| 1 | Driver Power Seat Switch |
| 2 | Passenger Power Seat Switch |
| 3 | Power Windows |
| 4 | Power Steering Column |
| 32 | Left Rear Window Switch |
| 37 | Right Rear Window Switch |
Rear Compartment Fuse Block (CTS Wagon)
The rear compartment fuse block is located on top of the battery, on the right side of the trunk. The battery access door must be removed to access the fuse block.
| Relays | Usage |
| 5 | Stop Lamps (Export Only) |
| 6 | Door Lock |
| 7 | Door Unlock |
| 8 | Fuel Door Unlock (Export Only) |
| 9 | Right Position Lamp (Export Only) |
| 10 | Console/Auxiliary Power Outlet |
| 11 | Not used |
| 12 | Side Marker Lamps |
| 13 | Left Position Lamps |
| Mini-Fuses | Usage |
| 14 | Right Position Lamp |
| 15 | Left Position Lamp |
| 16 | Door Lock |
| 17 | Console/Auxiliary Power Outlet |
| 18 | Rear Fog/Export Body Control Module (Export Only) |
| 19 | Rear Windshield Wiper/Washer |
| 20 | Windshield Washer Pump |
| 21 | Sunroof |
| 22 | Right Position Lamp (Export Only) |
| 23 | Regulated Voltage Control Sensor |
| 24 | Audio System (Radio) |
| 25 | Airbag System |
| 26 | Remote Keyless Entry/PASS‐Key® Theft Deterrent Module |
| 27 | Audio Speakers/Subwoofer |
| 28 | OnStar® System |
| 29 | Engine Control Module |
| 30 | Canister Vent |
| 31 | Fuel Pump |
| 33 | Stop Lamps (Export Only) |
| 34 | Theft Deterrent System/Universal Garage Door Opener |
| 35 | Memory Seat Module |
| 36 | Passenger Door Module |
| 38 | Rear Auxiliary Power Outlet |
| 39 | Amplifier |
| Circuit Breakers | Usage |
| 1 | Driver Power Seat Switch |
| 2 | Passenger Power Seat Switch |
| 3 | Power Windows |
| 4 | Power Steering Column |
| 32 | Left Rear Window Switch |
| 37 | Right Rear Window Switch |
Rear Compartment Fuse Block (CTS-V Wagon)
The rear compartment fuse block is located on top of the battery, on the right side of the trunk. The battery access door must be removed to access the fuse block.
| Relays | Usage |
| 5 | Stop Lamps (Export Only) |
| 6 | Door Lock |
| 7 | Door Unlock |
| 8 | Fuel Door Unlock (Export Only) |
| 9 | Right Position Lamp (Export Only) |
| 10 | Console/Auxiliary Power Outlet |
| 11 | Not used |
| 12 | Side Marker Lamps |
| 13 | Left Position Lamps |
| Mini-Fuses | Usage |
| 14 | Right Position Lamp |
| 15 | Left Position Lamp |
| 16 | Door Lock |
| 17 | Console/Auxiliary Power Outlet |
| 18 | Rear Fog/Export Body Control Module (Export Only) |
| 19 | Rear Windshield Wiper/Washer |
| 20 | Windshield Washer Pump |
| 21 | Fuel Pump |
| 22 | Right Position Lamp (Export Only) |
| 23 | Regulated Voltage Control Sensor |
| 24 | Audio System (Radio) |
| 25 | Airbag System |
| 26 | Remote Keyless Entry/PASS‐Key® Theft Deterrent Module |
| 27 | Audio Speakers/Subwoofer |
| 28 | OnStar® System |
| 29 | Engine Control Module |
| 30 | Canister Vent |
| 31 | Rear Differential Cooling Pump |
| 33 | Stop Lamps (Export Only) |
| 34 | Theft Deterrent System/Universal Garage Door Opener |
| 35 | Memory Seat Module |
| 36 | Passenger Door Module |
| 38 | Rear Auxiliary Power Outlet |
| 39 | Amplifier |
| Circuit Breakers | Usage |
| 1 | Driver Power Seat Switch |
| 2 | Passenger Power Seat Switch |
| 3 | Power Windows |
| 4 | Power Steering Column |
| 32 | Left Rear Window Switch |
| 37 | Right Rear Window Switch |
WARNING: Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.