Chevrolet 2012 Colorado Owner's Manual page 292

The trailer brake relay is located on
the bottom side of the battery
harness.
Oxygen Sensors,
Air Injection
O2 SNSR
Reactor (AIR)
Relay
Air Conditioning
A/C Control Head,
Power Seats
A/C Air Conditioning
CMPRSR Compressor
Antilock Brake
System (ABS),
ABS ABS Module,
Four Wheel Drive,
Gravity Sensor
ABS 1 ABS 1 (ABS Logic)
ABS 2 ABS 2 (ABS Pump)
AUX PWR 1 Accessory Power 1
AUX PWR 2 Accessory Power 2
BCK/UP Back-up Lights
Climate
BLWR
Control Fan
CLSTR Cluster
CNSTR Fuel Canister Vent
VENT Solenoid
Cruise Control
Switch, Inside
Rearview Mirror,
CRUISE Transfer Case
Control Module,
Brake Switch,
Clutch Disable
Power Door
DR/LCK
Locks (If Equipped)
Daylight Running
DRL
Lamps
Mass Air
Flow (MAF)
Sensor, Can Purge
ERLS Solenoid, Air
Injector
Reactor (AIR)
Relay
Electronic Throttle
ETC
Control (ETC)
Fog Lamps
FOG/LAMP
(If Equipped)
Front Park/Turn
Lamps, Driver and
FRT
Passenger Side
PRK LAMP
Power Window
Switches Lighting
FRT/AXLE Front Axle Actuator
Fuel System
FSCM
Control Module