Definition of Caution, Notice, and Important
The diagnosis and repair procedures in the GM Service Manual contain both general and specific Cautions, Notices, and Importants. GM is dedicated to the presentation of service information that helps the technician to diagnose and repair the systems necessary for the proper operation of the vehicle, however, certain procedures may present a hazard to the technician if they are not followed in the recommended manner. Cautions, Notices, and Importants are elements designed to prevent these hazards, however, not all hazards can be foreseen. This information is placed at strategic locations within the service manual. This information is designed to prevent the following from occurring
- Serious bodily injury to the technician
- Damage to the vehicle
- Unnecessary vehicle repairs
- Unnecessary component replacement
- Improper repair or replacement of vehicle components. Any caution or notice that appears in general information is referenced from the individual service categories.
CAUTION Defined
When encountering a CAUTION, you will be asked to take a necessary action or not to take a prohibited action. If a CAUTION is not heeded, the following consequences may occur
- Serious bodily injury to the technician
- Serious bodily injury to other technicians in the workplace area
- Serious bodily injury to the driver and/or passenger(s) of the vehicle, if the vehicle has been improperly repaired
NOTICE Defined
Notices call special attention to a necessary action or to a prohibited action. If a NOTICE is not heeded, the following consequences may occur
- Damage to the vehicle
- Unnecessary vehicle repairs
- Unnecessary component replacement
- Improper operation or performance of the system or component under repair
- Damage to any systems or components which are dependent upon the proper operation of the system or component under repair
- Improper operation or performance of any systems or components which are dependent upon the proper operation or performance of the system or component under repair
- Damage to fasteners, basic tools, or special tools
- The leakage of coolant, lubricant, or other vital fluids
IMPORTANT Defined
IMPORTANT statements emphasize a necessary characteristic of a diagnostic or repair procedure. IMPORTANT statements are designed to do the following
- Clarify a procedure
- Present additional information for accomplishing a procedure
- Give insight into the reason or reasons for performing a procedure in the manner recommended
- Present information that will help to accomplish a procedure in a more effective manner
- Present information that gives the technician the benefit of past experience in accomplishing a procedure with greater ease
Approved Equipment for Collision Repair Caution
| CAUTION | To avoid personal injury when exposed to welding flashes or to galvanized (Zinc Oxide) metal toxic fumes while grinding/cutting on any type of metal or sheet molded compound, you must work in a properly ventilated area, wearing an approved respirator, eye protection, earplugs, welding gloves, and protective clothing. |
Assistant Driving Caution
| CAUTION | An assistant should drive the vehicle while the technician checks for the location of the reported condition. Otherwise, personal injury could result. |
Battery Disconnect Caution
| CAUTION | Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components. |
Bleed Procedure Caution
| CAUTION | Remove all the air from the hydraulic brake system anytime the hydraulic brake system is opened for repair. The entire bleeding procedure must be followed. Failure to remove all the air in the hydraulic brake system will result in reduced braking performance and possible personal injury. |
Brake Dust Caution
| CAUTION | Avoid taking the following actions when you service wheel brake parts: Do not grind brake linings. Do not sand brake linings. Do not clean wheel brake parts with a dry brush or with compressed air. Some models or aftermarket brake parts may contain asbestos fibers which can become airborne in dust. Breathing dust with asbestos fibers may cause serious bodily harm. Use a water-dampened cloth in order to remove any dust on brake parts. Equipment is available commercially in order to perform this washing function. These wet methods prevent fibers from becoming airborne. |
Brake Fluid Irritant Caution
| CAUTION | Brake fluid may be irritating to the skin or eyes. In case of contact, take the following actions: Eye contact-rinse eyes thoroughly with water. Skin contact-wash skin with soap and water. |
Collision Sectioning Caution
| CAUTION | Sectioning should be performed only in the recommended areas. Failure to do so may compromise the structural integrity of the vehicle and cause personal injury if the vehicle is in a collision. |
Eye Protection Caution
| CAUTION | Approved safety glasses and gloves should be worn when performing this procedure to reduce the chance of personal injury. |
Gasoline/Gasoline Vapors Caution
| CAUTION | Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby. |
Glass and Sheet Metal Handling Caution
| CAUTION | When working with any type of glass or sheet metal with exposed or rough edges, wear approved safety glasses and gloves in order to reduce the chance of personal injury. |
Halogen Bulb Caution
| CAUTION | Halogen bulbs contain gas under pressure. Handling a bulb improperly could cause it to shatter into flying glass fragments. To help avoid personal injury: Turn off the lamp switch and allow the bulb to cool before changing the bulb. Leave the lamp switch OFF until the bulb change is complete. Always wear eye protection when changing a halogen bulb. Handle the bulb only by its base. Avoid touching the glass. Keep dirt and moisture off the bulb. Properly dispose of the used bulb. Keep halogen bulbs out of the reach of children. |
Moving Parts and Hot Surfaces Caution
| CAUTION | Avoid contact with moving parts and hot surfaces while working around a running engine in order to prevent physical injury. |
Road Test Caution
| CAUTION | Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage. |
Safety Glasses Caution
| CAUTION | Wear safety glasses in order to avoid eye damage. |
SIR Caution
| CAUTION | When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling and Enabling Zones. Failure to observe the correct procedure could cause deployment of the SIR components, personal injury, or unnecessary SIR system repairs. |
SIR Deployed Inflator Modules Are Hot Caution
| CAUTION | After deployment, the metal surfaces of the SIR component may be very hot. To help avoid a fire or personal injury: Allow sufficient time for cooling before touching any metal surface of the SIR component. Do not place the deployed SIR component near any flammable objects. |
SIR Inflator Module Coil Caution
| CAUTION | Improper routing of the wire harness assembly may damage the inflatable restraint steering wheel module coil. This may result in a malfunction of the coil, which may cause personal injury. |
SIR Inflatable Module Deployment Outside Vehicle Caution
| CAUTION | When deploying a SIR component for disposal, perform the deployment procedures in the order listed. Failure to observe the procedures in the order listed may result in personal injury. |
SIR Inflator Module Disposal Caution
| CAUTION | In order to prevent accidental deployment and the risk of personal injury, do not dispose of an undeployed inflator module as normal shop waste. Undeployed inflator modules contain substances that could cause severe illness or personal injury if their sealed containers are damaged during disposal. Use the following deployment procedures to safely dispose of an undeployed inflator module. Failure to observe the following disposal methods may be a violation of federal, state, or local laws. |
SIR Inflator Module Handling and Storage Caution
| CAUTION | When carrying an undeployed inflator module: Do not carry the inflator module by the wires or connector. Make sure the air bag opening points away from you. When storing an undeployed inflator module: Make sure the air bag opening points away from the surface on which the inflator module rests. Provide free space for the air bag to expand in case of an accidental deployment. When storing a steering column, do not rest the column with the air bag opening facing down and the column vertical. Lay the column on its side. Failure to observe these guidelines may result in personal injury. |
SIR Special Tool Caution
| CAUTION | Failure to observe the special tool recommendations and instructions could cause SIR deployment, personal injury, or unnecessary SIR system repairs. |
Vehicle Lifting Caution
| CAUTION | To avoid any vehicle damage, serious personal injury or death when major components are removed from the vehicle and the vehicle is supported by a hoist, support the vehicle with jack stands at the opposite end from which the components are being removed. |
Window Retention Caution
| CAUTION | When replacing stationary windows, use Urethane Adhesive Kit GM P/N 12346392 (Canadian P/N 10952983), or a urethane adhesive system meeting GM Specification GM3651G, to maintain original installation integrity. Failure to use the urethane adhesive kit will result in poor retention of the window which may allow unrestrained occupants to be ejected from the vehicle resulting in personal injury. |
Work Stall Test Caution
| CAUTION | One or more of the following guidelines may apply when performing specific required tests in the work stall: When a test requires spinning the drive wheels with the vehicle jacked up, adhere to the following precautions: Do not exceed 56 km/h (35 mph) when spinning one drive wheel with the other drive wheel stopped. This limit is necessary because the speedometer indicates only one-half the actual vehicle speed under these conditions. Personal injury may result from excessive wheel spinning. If all of the drive wheels are spinning at the same speed, do not exceed 112 km/h (70 mph). Personal injury may result from excessive wheel spinning. All persons should stay clear of the rotating components and the balance weight areas in order to avoid possible personal injury. When running an engine in the repair stall for an extended period of time, use care not to overheat the engine and the transmission. When a test requires jacking up the vehicle and running with the wheels and brake rotors removed, adhere to the following precautions: Support the suspension at normal ride height. Do not apply the brake with the brake rotors removed. Do not place the transmission in PARK with the drive axles spinning. Turn Off the ignition in order to stop the powertrain components from spinning. |
Belt Dressing Notice
Note. Do not use belt dressing on the drive belt. Belt dressing causes the breakdown of the composition of the drive belt. Failure to follow this recommendation will damage the drive belt.
Brake Caliper Supporting to Prevent Hose Damage Notice
Note. Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.
Brake Fluid Effects on Paint and Electrical Components Notice
Note. Avoid spilling brake fluid onto painted surfaces, electrical connections, wiring, or cables. Brake fluid will damage painted surfaces and cause corrosion to electrical components. If any brake fluid comes in contact with painted surfaces, immediately flush the area with water. If any brake fluid comes in contact with electrical connections, wiring, or cables, use a clean shop cloth to wipe away the fluid.
Clean, Dry, Low Pressure Gas Source Notice
Note. Use the EVAP Pressure/Purge Diagnostic Station J 41413 in order to provide a clean, dry, low pressure gas source. Do not substitute any other pressurized gas source. Damage may result to the EVAP system.
Clearcoat/Ultraviolet Screeners Notice
Note. Removing more than 0.5 mils of the clearcoat can result in early paint failure. The clearcoat contains ultraviolet screeners. Do not finesse sand more than what is required to remove the defect.
Component Fastener Tightening Notice
Note. Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.
Excessive Force and Oxygen Sensor Notice
Note. The oxygen sensor may be difficult to remove when the engine temperature is below 48°C (120°F). Excessive force may damage threads in the exhaust manifold or the exhaust pipe.
Fastener Notice
Note. Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Heated Oxygen and Oxygen Sensor Notice
Note. Do not remove this pigtail from either the heated oxygen sensor (HO2S) or the oxygen sensor (O2S). Removing the pigtail or the connector will affect sensor operation. Handle the oxygen sensor carefully. Do not drop the HO2S. Keep the in-line electrical connector and the louvered end free of grease, dirt, or other contaminants. Do not use cleaning solvents of any type. Do not repair the wiring, connector or terminals. Replace the oxygen sensor if the pigtail wiring, connector, or terminal is damaged. This external clean air reference is obtained by way of the oxygen sensor signal and heater wires. Any attempt to repair the wires, connectors, or terminals could result in the obstruction of the air reference and degraded sensor performance. The following guidelines should be used when servicing the heated oxygen sensor: Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors. These materials may get into the sensor causing poor performance. Do not damage the sensor pigtail and harness wires in such a way that the wires inside are exposed. This could provide a path for foreign materials to enter the sensor and cause performance problems. Ensure the sensor or vehicle lead wires should not be bent sharply or kinked. Sharp bends or kinks could block the reference air path through the lead wire. Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize the ground wired sensor may rely on this ground as the only ground contact to the sensor. Removal of the ground wire will cause poor engine performance. Ensure that the peripheral seal remains intact on the vehicle harness connector in order to prevent damage due to water intrusion. The engine harness may be repaired using Packard's Crimp and Splice Seals Terminal Repair Kit. Under no circumstances should repairs be soldered since this could result in the air reference being obstructed.
Heated Oxygen Sensor (HO2S) Resistance Learn Reset Notice
Note. When replacing the HO2S perform a code clear with a scan tool, regardless of whether or not a DTC is set. Performing a code clear will reset the HO2S resistance learned value. Failure to perform a code clear may result in an HO2S failure.
Silicon Contamination of Heated Oxygen Sensors Notice
Note. Contamination of the oxygen sensor can result from the use of an inappropriate RTV sealant (not oxygen sensor safe) or excessive engine coolant or oil consumption. Remove the HO2S and visually inspect the portion of the sensor exposed to the exhaust stream in order to check for contamination. If contaminated, the portion of the sensor exposed to the exhaust stream will have a white powdery coating. Silicon contamination causes a high but false HO2S signal voltage (rich exhaust indication). The control module will then reduce the amount of fuel delivered to the engine, causing a severe driveability problem. Eliminate the source of contamination before replacing the oxygen sensor.
Test Probe Notice
Note. Do not insert test equipment probes (DVOM etc.) into any connector or fuse block terminal. The diameter of the test probes will deform most terminals. A deformed terminal will cause a poor connection, which will result in a system failure. Always use the J-35616 GM-Approved Terminal Test Kit or the J 42675 Flat-Wire Probe Adapter in order to front probe terminals. Do not use paper clips or other substitutes to probe terminals. When using the J-35616 GM-Approved Terminal Test Kit, ensure the terminal test adapter choice is the correct size for the connector terminal. Do not visually choose the terminal test adapter because some connector terminal cavities may appear larger than the actual terminal in the cavity. Using a larger terminal test adapter will damage the terminal. Refer to the J-35616 GM-Approved Terminal Test Kit label on the inside of the J-35616 GM-Approved Terminal Test Kit for the correct adapter along with the connector end view for terminal size.
Three-Way Catalytic Converter Damage Notice
Note. In order to avoid damaging the replacement three-way catalytic converter, correct the engine misfire or mechanical fault before replacing the three-way catalytic converter.
Transmission Fluid Vent Cap Removal Notice
Note. The fluid vent cap must be removed before checking the fluid level, in order to ensure the proper level. Improper fluid level may damage the transmission.
Window Edge Damage Notice
Note. Avoid damage to the window from impacting objects due to an exposed edge. The window must be 1 mm (0.025 in) below the surface of the sheet metal to avoid window damage.
