ASE Practice Test (B4: Structural Analysis & Damage Repair) 3 — Questions and Answers
Question 1: Which type of welding is the OEM-approved method for most structural panel replacement in modern collision repair?
- Oxyacetylene (gas) welding
- MIG (GMAW) welding with a properly set welder using the vehicle manufacturer's wire and settings (Correct answer)
- Flux-core wire welding (FCAW)
- Resistance spot welding only in all cases
Correct answer: MIG (GMAW) welding with a properly set welder using the vehicle manufacturer's wire and settings
Most OEM repair procedures specify MIG (Gas Metal Arc Welding / GMAW) welding for structural panel replacement. It provides the required strength, can be used for plug welds that replicate factory spot welds, and produces less heat distortion than gas welding. OEM procedures specify wire type, diameter, gas mixture, and specific weld settings. Flux-core welding is generally not approved for structural body repairs.
Question 2: A technician is replacing a front rail section using the sectioning method. What is a critical requirement for the location of the sectioning cut?
- The cut must be made at any convenient location on the rail
- The cut must be located in an area specified by the OEM repair procedure, avoiding high-stress zones and crush zones (Correct answer)
- The cut should be made at the point of maximum damage
- The cut location is determined only by part availability
Correct answer: The cut must be located in an area specified by the OEM repair procedure, avoiding high-stress zones and crush zones
Rail sectioning cuts must be placed only where vehicle manufacturers designate as acceptable cut locations. These areas are selected to avoid engineered crush zones (which must remain intact to absorb future crash energy) and areas of high stress concentration. Cuts made in wrong locations compromise the vehicle's crash safety system. OEM repair procedures or I-CAR training specify the approved cut locations.
Question 3: When performing a sectioning weld on a structural rail using an offset (butt) joint, what is the minimum recommended weld overlap distance?
- 5mm overlap
- 25mm (1 inch) or as specified by the OEM (Correct answer)
- 50mm (2 inches) always
- No overlap — butt weld flush
Correct answer: 25mm (1 inch) or as specified by the OEM
OEM sectioning procedures typically require a minimum 25mm (approximately 1 inch) offset/stagger of the cut on each flange, or an offset butt joint, to distribute the weld stress area. Proper overlap and offset ensure that the weld joint does not become a single failure point. Always follow the specific OEM repair procedure dimensions, which may vary by vehicle and rail design.
Question 4: After structural repairs on a vehicle equipped with side-curtain and side-impact airbags, what must the technician verify before closing the repair order?
- That the airbag deployment light is off and scan for airbag DTCs; verify all sensors and mounting points are restored to spec (Correct answer)
- Only that the airbag light is off
- That the airbag module was replaced
- That the air bags were manually deployed during repair
Correct answer: That the airbag deployment light is off and scan for airbag DTCs; verify all sensors and mounting points are restored to spec
Modern vehicles have numerous airbag sensors mounted in structural panels, pillars, and sills. After structural repair, the technician must verify all sensor mounting locations are restored to exact OEM specifications, perform a scan for airbag system DTCs, and ensure the airbag warning light is extinguished. Improperly mounted sensors or damaged wiring can prevent airbag deployment in a future crash, which is a serious safety liability.
Question 5: Which type of corrosion protection should be applied inside sealed structural cavities after welding?
- External body seam sealer only
- Cavity wax or anti-corrosion compound injected through access holes (Correct answer)
- Undercoating applied to the outside of the panel
- Weld-through primer painted over the welds externally
Correct answer: Cavity wax or anti-corrosion compound injected through access holes
The interior of closed structural sections (box sections, pillars, rails) cannot be accessed after assembly. Factory cavity wax is injected through small holes during manufacturing to prevent internal corrosion. After repair and welding, cavity wax or anti-corrosion compound must be re-applied through access holes to restore this protection. Failure to do so leads to internal corrosion that can compromise structural integrity over time.
Question 6: What is the purpose of measuring diagonal dimensions across the engine compartment during damage analysis?
- To measure engine compartment volume for replacement part selection
- To detect sidesway and diamond damage by comparing the two diagonal measurements across the compartment (Correct answer)
- To locate the vehicle identification number (VIN)
- To measure the radiator support length
Correct answer: To detect sidesway and diamond damage by comparing the two diagonal measurements across the compartment
Comparing diagonal measurements from corner to corner across the engine compartment (and other areas) is a fundamental damage analysis technique. If the two diagonals are equal, the compartment is square. If one diagonal is longer than the other, it indicates the compartment has shifted into a parallelogram shape (sidesway or diamond damage). This requires further three-dimensional measurement and straightening.
ASE Practice Test (B4: Structural Analysis & Damage Repair) 3
Which type of welding is the OEM-approved method for most structural panel replacement in modern collision repair?