Print Download PDF

3 Vehicle structure

3-4 Threshold for requiring specialist repair certification

The following information gives guidance to vehicle inspectors in determining whether or not a light vehicle (including motorcycles and mopeds where applicable) and heavy vehicles undergoing entry certification in New Zealand requires repair certification by a specialist repair certifier.

Note 1

Specialist repair certifier in this case means a light vehicle repair certifier or heavy vehicle specialist certifier as applicable to the vehicle class.

Important: If the vehicle documentation (eg a registration document or invoice) contains the words ‘statutory’, 'written off', ‘write-off’, ‘salvage’, ‘junked’ or ‘non-repairable’ or similar the vehicle must be referred to a specialist repair certifier.

Applicable legislation

A repair to a vehicle (including its structure, systems, components or equipment) must restore the damage or wear to within safe tolerance of its state when manufactured or modified.

Criteria for reporting structural damage or corrosion

The criteria detailed below must be used when deciding if any damage or corrosion should be referred to a specialist repair certifier. All damage meeting this criteria and found in the energy management path areas must be referred to a specialist repair certifier.

Structural components that can be unbolted, such as doors with intrusion beams and sub frames, which are damaged or corroded are a reason for rejection. However, these parts can be replaced by the owner and re-inspected without the need for repair certification.

The important distinction when applying these criteria is:

  • Whether the area identified as damaged by impact, previous repair, or corrosion is structural or cosmetic, and
  • Whether the extent of damage is sufficient to compromise the structural integrity of the motor vehicle, or
  • Whether evidence of damage, previous damage repair, or heat damage is present in a structural area, or energy management path of the motor vehicle.

Photographs illustrating examples of structural damage and corrosion are shown in Reference material 71.

Damage/deterioration that must be referred to a specialist repair certifier

Under-body impact damage

A vehicle must be referred to a specialist repair certifier if it has underbody damage as a result of a collision with a substantial object, sufficient to cause the splitting of seam welds, distortion of suspension members or mounting points, or tearing of metal structures, excluding floorpan stiffeners.

Note 2

When distinguishing between floorpan stiffening members and cross-members, note that a member that runs through the line of a seat or occupant area will not be an energy absorbing member (ie its purpose is to reinforce the floorpan), while a member that runs alongside a seat or occupant area should be treated as an energy absorbing member (ie a chassis rail).

Denting or distortion
  • A vehicle must be referred to a specialist repair certifier if there is any discernible denting or distortion to the folds or swages in the dog leg, sill panel or structure of the inner/outer sill weld seam, other than minor scraping.
  • A vehicle must be referred to a specialist repair certifier if rocker panels (outer sills) are dented or creased lengthways along the sill and the depth of the crease exceeds 25mm (see Figure 3-4-1).
  • A vehicle must be referred to a specialist repair certifier if rocker panels (outer sills) are vertically dented or creased across the sill regardless of the depth of the crease or dent (see Figure 3-4-1).
Figure 3-4-1. Outer sills cross section and rocker panels

5

5

Crush zones and kick-up areas

A vehicle must be referred to a specialist repair certifier if there is distortion of the longitudinal rails affecting the front and rear crush zones and kick-up areas.

Crossmembers

A vehicle must be referred to a specialist repair certifier if there is denting or distortion of the crossmember as a result of collision with an object.

Cracking

A vehicle must be referred to a specialist repair certifier if there is cracking in:

  • the unibody or chassis
  • any crossmembers and subframes
  • a load bearing member, or energy management paths in unibody structures
  • the body of a vehicle with a body-over-frame chassis in the energy management paths, engine mounts, suspension mounts, body mounts, pillars, or sills.
Repaired damage

A vehicle must be referred to a specialist repair certifier if signs of repair, rust prevention or under-sealing to any part of the vehicle structure are evident  (for exceptions to this requirement see Technical bulletin 44: Rust prevention or under-sealing on late model cars from the UK)  (for rust heave on heavy vehicle chassis refer to Figure 3-4-4).

Heavy Motor Vehicle repairs that do not require a specialist repair certification (LT400)

This guide contains the list of repairs to heavy vehicles that do not require heavy vehicle specialist inspection and certification, ie an LT400.

1. Replacement of bolted components. Except for components that specifically require specialist inspection and certification. (eg log bolster attachments, drawbars and drawbeams, etc)

2. Repairs to the first failures of chassis cross-members that are NOT one of the following:

a) the first or last cross-member of the chassis

b) cross-members that are fitted within 500mm from engine or transmission mounts

c) cross-members that are fitted within 500mm from a suspension support (eg spring hanger)

d) cross-members to which a driveshaft centre bearing is fitted

e) cross-members that are fitted to support a:

  • ball-race turntable
  • tow coupling
  • fifth-wheel
  • king pin
  • bolster attachment
  • hoist, hydraulic cylinder of a tipping body, or any other devices that may place a concentrated load on the chassis.

3. Repairs to coaming rails that do not support certified load anchorage points, including stock crate j-hooks.

4. Tow-eyes fitted to the front of a vehicle for recovery purposes.

5. Repairs to a component of a freight or bus monocoque body (ie not a truck’s driver/passenger cab) if the component is not part of the body framework. (eg body panels)

Note: The vehicle inspector may reject the component during the Certification of Fitness inspection if the welding that has been carried out as part of the repair is of poor quality, established by means of visual inspection.

Supplementary Restraint System (SRS): Airbags and seatbelt pretensioners

A vehicle must be referred to a specialist repair certifier if it has a deployed airbag or seatbelt pretensioner, or there is evidence of repairs to or tampering with airbag module covers. (including colour variations in plastic covers to steering wheels, dash panels, interior trim, or non-original stitching to seat mounted airbags).

Note 3

Unless there is evidence that the airbag has been deployed, it is not expected that the vehicle go to a specialist repair certifier if it has a sports steering wheel fitted with no airbag at entry and is failed and it is requested that the OE steering wheel be reinstated.

If the airbag has not been deployed it is only expected that the original steering wheel be reinstated and an SRS declaration issued in line with Technical bulletin 29.

Water or fire damage
  • A vehicle must be repair certified by a specialist repair certifier if there is evidence that it has suffered water or fire damage (see Technical bulletin 2).
Note 4

For the purposes of the threshold for requiring specialist repair certification, evidence of water damage may be physical evidence, or it may be that the vehicle has been written-off for insurance purposes as a result of water damage.

Corrosion damage
  • Corrosion damage is where the metal has been eaten away, which is evident by pitting. The outward signs of such corrosion damage are typically displayed by the swelling of a panel between spot welds, or lifting or bubbling of paint. In extreme cases, the area affected by the corrosion damage will fall out and leave a hole.

    A vehicle must be specialist repair certified if there is corrosion damage in any structural area, as indicated in the shaded areas of Figure 3-4-2.
Note 5

Corrosion damage includes any signs of ‘rust bleed’.

Rust bleed is a rust coloured stain or mark that appears around an area of corrosion that may not be visible. Rust bleed is most commonly found where panels join or overlap when corrosion has started between the two surfaces and moisture has caused a rust stain or mark to run onto the external surface.

  • Perforated corrosion is where the metal is corroded to the extent that it has holes, or holes are exposed when rust scale is removed. If metal is badly pitted causing a loss of metal thickness it must also be treated as perforated corrosion.
  • Rust heave on a heavy vehicle chassis must be assessed in accordance with the requirements in the VIRM: In-service certification 3-1 Structure (heavy vehicles). See also Figure 3-4-4.

    If there is perforated corrosion in any other (non-structural) area, as indicated in the non-shaded areas of Figure 3-4-2, the vehicle requires to be reported.
Figure 3-4-2. Structural corrosion damage limits

5

  • Repair of corrosion on ‘bolt on’ parts (doors, bonnets etc) within a 150mm circle around the outside of hinge or latch components will require specialist repair certification. These ‘no corrosion’ zones are circled in Figure 3-4-3.
  • Replacement of these parts will not require specialist repair certification, provided the inspector is satisfied that safety systems are not affected (eg side intrusion beams, burst proof locks, frontal impact systems).
Figure 3-4-3. Hinge and latch anchorage corrosion damage limits

Hinge and latch anchorage corrosion damage limits

Figure 3-4-4. Rust heave limits

rust heave limits

Rust heave beyond the limits described above is acceptable only if an HVS certifier has confirmed this in writing. The vehicle may continue without repair until an expiry date specified by the HVS certifier. Where no expiry date is specified the vehicle must be referred to an HVS certifier for another assessment at the next CoF inspection.

Regardless of any expiry date, an inspector may refer the vehicle to an HVS certifier if he/she suspects that the safety of the vehicle is compromised, eg due to excessive corrosion or chassis cracking. If the chassis is repaired, an LT400 is required.

Permitted cosmetic damage/deterioration

Cosmetic damage to the motor vehicle’s outer body panels is permitted, providing it does not affect the structural integrity of chassis, the energy management paths, or any of the bonded or welded seams or joints as a result of the manufacturing process.

Cosmetic parts on a unibody chassis are generally bolt on items such as the front guard, boot-lid, and in most cases the doors.

Photographs illustrating examples of cosmetic damage are shown in Reference material 72.

Inspection

A list of specific types of damage follows. It explains the extent to which damage is allowed before a vehicle must be reported.

Underbody impact damage

A vehicle is not required to be referred to a specialist repair certifier if it has minor underbody impact damage as a result of ‘grounding’ the vehicle or some scraping of the sill seams.

A vehicle is not required to be referred to a specialist repair certifier if there is crushing or tearing of floorpan stiffening members (Note 5), provided it does not affect any internal cross-members designed for side-impact protection.

Note 6

When distinguishing between floorpan stiffening members and cross-members, note that a member that runs through the line of a seat or occupant area will not be an energy absorbing member (ie its purpose is to reinforce the floorpan), while a member that runs alongside a seat or occupant area should be treated as an energy absorbing member (ie a chassis rail).

Denting or distortion

A vehicle is not required  to be referred to a specialist repair certifier if rocker panels (outer sills) are dented or creased lengthways along the sill to a depth of less than 25mm.

Cross-members

A vehicle is not required to be referred to a specialist repair certifier if it has minor jacking damage to a cross-member, provided there is no indication of loss of steering or suspension alignment.

Repaired damage

A vehicle with repaired damage is not required to be referred to a specialist repair certifier if repairs are only to correct cosmetic damage to the outer body panels, provided the vehicle inspector is able to discern the extent of the damage and confirm that none of the vehicle manufacturer’s seams or joints have been disturbed during the repair.

Vehicles flagged for damage at the border

When a Border Inspection Organisation identifies damage on a vehicle during the border check, the vehicle will be flagged as damaged on LANDATA. If the vehicle inspector determines that the damage does not exceed the threshold for requiring specialist repair certification, an application must be made to remove the damage flag.

A ‘Request to remove border damage flag’ form is available in Reference material 17. The vehicle inspector must complete this form and give it to the IO supervisor authorised to remove damage flags.

Repair certification and damage flags

A light vehicle may have a damage flag removed if it has been repaired in accordance with the requirements of the VIRM: Light vehicle repair certification and it has been requested by a repair certifier, as mentioned in the LT308.

A heavy vehicle may have a damage flag removed if it has been repaired and certified (LT400) by a heavy vehicle specialist certifier with the appropriate category.

Page amended 2 December 2019 (see amendment details).