The checks also identified significant structural differences between the Canberra vehicles and similar models in Sydney, which has given local transport officials confidence the ACT will avoid the issue.

An inspection of LRV011 in November, which included removing seats, found there were no cracks visible in the same locations where the cracks on the Sydney fleet were identified.

The vehicle inspected in Canberra has travelled the longest distance on the city's route between Gungahlin and the city, having completed 192,000 kilometres.

Transport Minister Chris Steel will on Thursday tell the Legislative Assembly the government has a degree of confidence the ACT's light rail vehicles will not experience the same fault as the Sydney fleet because the vehicles in Canberra are structurally different.

While both the affected Sydney light rail vehicles and the Canberra fleet are designated as CAF Urbos 100, Mr Steel will say there are key differences in design and construction.

"Since the identification of issues with the Sydney fleet, Transport Canberra and Canberra Metro have proactively undertaken inspections of the Canberra light rail fleet," Mr Steel will say.

"This has initially focused on examination of LRV011 - the vehicle with the highest number of kilometres travelled in the Canberra fleet.

"Since coming into service this LRV has clocked up an impressive 192,000 kilometres, so if there were issues associated with wear and tear we'd expect to see them on this vehicle first."

The checks have focused on the bogie box, which is where cracking in Sydney was identified. The bogie box is where the wheelset, known as a bogie, is attached to the light rail vehicle.

The bogie box also has brackets called bump stops which help the vehicle to turn; the stiffening web and brackets around the bump stocks are where the cracks in the Sydney fleet were found, Mr Steel will say.

"On 11 November, 2021, the seats in a car of LRV11 were then removed to allow visual inspection of the bogie box from above. This is not a regular inspection activity as the seats are not usually removed for standard maintenance checks," he will say.

"No evidence of cracking was visible between the upper and lower bogie box, or the lower bogie box and the floor."

A report due to be tabled in the Assembly said the Canberra light rail fleet had aluminium components in the area affected by cracks in the Sydney fleet, which used mild steel.

"[The vehicle manufacturer] has advised that LRVs with this aluminium configuration are used on 14 projects globally in addition to Canberra's light rail network. They have confirmed no other Urbos fleets with this configuration have reported issues with vehicle cracking to date," the government's response said.

The Spanish company CAF, which manufactured the vehicles, has also improved its inspection regime, which includes internal checks of the bogie boxes in Canberra.

"A proportion of the fleet will then be checked annually to provide ongoing assurance of safety and serviceability," the government's response said.

The ACT's fleet includes an extra structural element between the upper and lower bogie boxes, extra support at the corners of the upper bogie box, additional stich welding to join the upper and lower bogie boxes and a different structure for lifting the vehicle with an external jack.

"In aggregate, these changes demonstrate the structural differences in the components which have experienced cracking on the Sydney fleet," the government's response said.

"These differences indicate that CAF has made improvements to LRB designs over time, resulting in a progressive evolution of rolling stock in service around the world.

"The Sydney Inner West Light Rail fleet entered service in 2014 and 2015. By comparison, the Canberra fleet entered service several years later in April 2019."

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Mr Steel will say the government will closely follow investigations into light rail faults in other cities but the ACT government is well-prepared in the event contingency services are required.

"I make a commitment that the government will continue to transparently inform Canberrans on the outcomes of this work," he will say.

The government's report to the Assembly was prompted by a motion moved by the opposition's spokesman on transport, Mark Parton, who last month called on the government to outline its contingency plans and risks to the territory's light-rail fleet.

The government agreed to the motion and committed to reporting on safety checks sooner.

NSW transport authorities have moved to suspend services on an inner-west Sydney light rail line for up to 18 months after cracks were identified in its fleet, a similar model to Canberra's fleet.

The Australian rail safety regulator has confirmed to the ACT government it is not investigating Canberra's light rail fleet, because it was structurally different to Sydney's fleet, which was under review.

The public-private partnership responsible for running light rail services in Canberra is required to maintain the infrastructure and fleet includes CAF, the vehicle manufacturer.

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