More than 50 Toyota employees were injured, and the company's assembly plant in Tianjin shut down temporarily. One day after the explosion, Toyota was able to check the status of its supplier network down through Tier 4, Young said.
"The next morning, everyone in Japan and North America knew who they had to call to measure the risk," Young said. "We knew exactly how many subtier suppliers we had within a radius of Tianjin. [Toyota and its Tier 1 suppliers] could immediately start calling them to find out the overall impact."
Toyota developed the monitoring system after an earthquake and tsunami devastated Japan in 2011. The disaster revealed a series of formerly undetected supplier bottlenecks that choked off the flow of parts to Toyota and other automakers.
Assembly plants were shut down for weeks while suppliers scrambled to repair damaged factories.
To identify bottlenecks, Toyota launched a census of Tier 2, 3 and 4 suppliers. Now, if a key plant is knocked out by flood, fire or storm, suppliers can transfer production to other sites. In some cases, suppliers have stockpiled key components.
The census and monitoring system are now complete, Young says.
For some components, Toyota can trace its supplier network down to raw materials, if necessary. "The deepest level we have is Tier 6," Young said. "Once we get to the steel in the steel mill, we don't go down to iron ore or coal."
A few suppliers refused to identify their vendors, Young acknowledged. But these companies have set up their own monitoring systems. "We understand their processes," Young said. "So if we have issues, we can reach out to them for a response."