Definition of Caution, Notice & 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
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. |
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. |
Battery Disconnect Caution
| CAUTION | Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components. |
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 irritate eyes and skin. In case of contact, take the following actions: Eye contact-rinse thoroughly with water. Skin contact-wash with soap and water. If ingested-consult a physician immediately. |
Camshaft Holding Tool Caution
| CAUTION | The camshaft holding tools must be installed on the camshafts to prevent camshaft rotation. When performing service to the valve train and/or timing components, valve spring pressure can cause the camshafts to rotate unexpectedly and can cause personal injury. |
Compressed Valve Spring Caution
| CAUTION | Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury. |
Exhaust Service Caution
| CAUTION | In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool. |
Eye Protection Caution
| CAUTION | Approved safety glasses and gloves should be worn when performing this procedure to reduce the chance of personal injury. |
Foam Sound Deadeners Caution
| CAUTION | Foam sound deadeners must be removed from areas within 152.4 mm (6 in) of where flame is to be used for body repairs. When reinstalling foam sound deadeners, avoid inhaling fumes as bodily injury may result. |
Fuel & Evaporative Emission Pipe Caution
| CAUTION | In order to reduce the risk of fire and personal injury observe the following items: Replace all nylon fuel pipes that are nicked, scratched or damaged during installation, do not attempt to repair the sections of the nylon fuel pipes Do not hammer directly on the fuel harness body clips when installing new fuel pipes. Damage to the nylon pipes may result in a fuel leak. Always cover nylon vapor pipes with a wet towel before using a torch near them. Also, never expose the vehicle to temperatures higher than 115°C (239°F) for more than one hour, or more than 90°C (194°F) for any extended period. Apply a few drops of clean engine oil to the male pipe ends before connecting fuel pipe fittings. This will ensure proper reconnection and prevent a possible fuel leak. (During normal operation, the O-rings located in the female connector will swell and may prevent proper reconnection if not lubricated.) |
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 & 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. |
Hot Exhaust System Caution
| CAUTION | While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system. |
Hood Hold-Open Device Caution
| CAUTION | When a hood hold open device is being removed or installed, provide alternate support to avoid the possibility of damage to the vehicle or personal injury. |
Moving Parts & Hot Surfaces Caution
| CAUTION | Avoid contact with moving parts and hot surfaces while working around a running engine in order to prevent physical injury. |
Protective Goggles and Glove Caution
| CAUTION | Always wear protective goggles and gloves when removing exhaust parts as falling rust and sharp edges from worn exhaust components could result in serious personal 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. 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 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 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 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 & 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. |
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 and strap the vehicle to the hoist. |
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. When running an engine in the work stall, use the exhaust removal system to prevent breathing dangerous gases. |
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 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 & 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.
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.
Exhaust System Inspection Notice
Note. When inspecting or replacing exhaust system components, make sure there is adequate clearance from all points on the underbody to prevent overheating of the floor pan and possible damage to the passenger compartment insulation and trim materials.
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.
Flex Decoupler Notice
Note. Do not over-flex or damage the flex decoupler joint when moving the flex decoupler joint from the normal mounting position. The flex decoupler joint will flex a maximum of six degrees which is equivalent to the pipes connected at the joint which move 1 inch for each foot length of pipe. A three foot pipe would move a maximum of three inches.
Heated Oxygen Sensor Resistance Learn Reset Notice
Note. When replacing the HO2S perform the following: A code clear with a scan tool, regardless of whether or not a DTC is set HO2S heater resistance learn reset with a scan tool, where available Perform the above in order to reset the HO2S resistance learned value and avoid possible HO2S failure.
OBDII Symbol Description Notice
Note. The OBD II symbol is used on the circuit diagrams in order to alert the technician that the circuit is essential for proper OBD II emission control circuit operation. Any circuit which fails and causes the malfunction indicator lamp (MIL) to turn ON, or causes emissions-related component damage, is identified as an OBD II circuit.
Pipe Wrench Positioning Notice
Note. The pipe wrench must be placed at the valve end of the steering gear and positioned up against the inner tie rod housing. Placing the pipe wrench in any other location will cause damage to the steering gear.
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.
Steering Wheel in the Full Turn Position Notice
Note. Do not hold the steering wheel in the full turn position longer than 5 seconds, as damage to the steering pump may result.
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 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.
Torque Reaction Against Timing Drive Chain Notice
Note. A wrench must be used on the hex of the camshaft when loosening or tightening in order to prevent component damage. Failure to prevent the torque reaction against the timing drive chain can lead to timing drive chain failure.
Valve Lifter Priming Notice
Note. Ensure each valve lifter is filled with clean engine oil and the valve lifter does not tip over (plunger down) before the installation of the valve lifters. The loss of oil in the valve lifter lower pressure chamber or the dry stroking/cycling of the valve lifter plunger will allow air to travel into the high pressure chamber of the valve lifter. Air in the high pressure chamber of the valve lifter may not be purged causing extensive engine component damage.
