Toyota Motor Manufacturing

1、As Doug Friesen, what would you do to address the seat problem? In particular, where would you focus your attention and solution efforts? *

Clearly, this issue began after the styles extended. As Doug Friesen, I would use three methods to tackle the problems:

The first method is about KFS process. Given that the majority of seat defects are from KFS and KFS cannot supply replacements for defective seats on time, TMM should participate in KFS’S quality control Process and help them find the root cause of the problem. TMM could also consider going over to KFS and watching the production lines to see if he can notice any significant problems.

The second method is about the supplier. Since the supplier process operates under Just In Time (JIT), I would suggest having several suppliers, which can tackle this overburden. Due to the product proliferation from 3 styles and 4 colors to 36 different styles, it seems that KFS cannot handle the problem in a short time and seats cannot match each particular car all the time. So, having multi-suppliers helps the weight of only a single supplier.

The last is about the design. The designer should review the client needs to see whether so many different seat styles are actually necessary.

My attention is focusing on the specific problems and determining if the solution is feasible.

1. The run ratio is down from 95 % to 85 %, which makes the sales company not get cars on time.
2. Numerous cars have seat problems due to product proliferation problems.
3. Too many cars need off-line operations, which increases off-line inventory
4. The number of andon pulls has been increasing.
5. Cars leave the overflow parking lot too slowly.  
6. Overtime of worker has been required to make up lost production.
7. Group leaders have not taken counter-measures to address the seat problems. The seat problems have gone unresolved for a long time.  

2、Where, if at all, does the routine for handling defective seats deviate from the principles of the Toyota Production System? *

Three parts of the routine for handling defective seats violated the Jidoka concept.

Firstly, production is not stopped when a seat problem is identified. Jidoka means making production problems instantly self-evident and workers are empowered to stop production when production/quality problems are detected. However, it seems that the staff hasn’t practiced Jidoka very well.

Secondly, seat problems are not investigated on the line. Jidoka motivates rapid problem solving and stop producing whenever problems were detected. Staff at the overflow lot didnot discover the cause of the seat problems.

Last but not least, the current process for responding to the seat problems breaks the link between when and where the problems are caused and when and where they are finally treated.  The seat problems are not be solved in real time, but just be left in the rework area.

3、Do you think the line should be stopped when the seat assembly station identifies a defective seat? yes or no

no

4、Please justify your answer to the above question.

Stopping the line is not an option since it won’t solve the problem. The reason for stopping the line is to diagnose the causes of the problems with QC and, while repairing the cars in the clinic area, fed the information back to the appropriate teams. However, most of the seat problems are material flaws or missing parts, which is already known. Additionally, this problem needs several days to be corrected that the line cannot wait such a long time. If workers find a defective seat, it would take one or two days for KFS to delivery seat replacements. Sometimes, it would take a long time since KFS sends incorrect seat assemblies.  In many cases, the replacement seats are not installed in a timely manner.

What options exist to address the problem? What would you recommend? Why?

Option one: Introduce Jidoka method to KFS to identify the source of the problem and correct it on site. Jidoka method would allow visual control and make cars with seat problems more self-evident. Both KFS and TMM will benefit from the TPS integration. For example, Place a QC person at the seat arrival dock to check for defects before sending seats to the line. By doing this, KFS could follow Toyota’s philosophy and stops the problems before entering the facility, there would be less fix and return issues, which would keep workflow steady. However, it is time-consuming and KFS could feel invaded and lack of trust.

• Option two: Maintain an on-site supply of safety stock(buffer). Safety stock would reduce time wasting and enables smoother flow in the production process. Meanwhile, this method contradicts the principle of TPS and JIT to eliminate waste and may require more maintenance in terms of staffing and cost.
• Option three: Additional seat supplier. TMM can get an addition supplier since they are in a row of expanding their seating styles. I assume that KFS has exhibited vulnerability to style proliferation. Multi-suppliers could reduce the number of KFS issues and keep a more efficient production line. One thing we cannot ignore is that it would be expensive to implement change. For example, the further location of other suppliers would request a higher cost of implementing, compared with the geographically close location of  KFS.
• Option four: Reduce the number of seat variations offered. The designer should review the client needs to see whether so many different seat styles are actually necessary. This would lower the demand for KFS and decrease the chance of defective seat problems. But its method would provide less variety for consumers and contradicts the strategy of Toyota—“Better cars for more people”.
• Option five: Add more space. TMM could designate an area for the defected seat vehicles which will allow them to easily identify and examine quickly to save time. And assigning a space is not a problem for TMM, but the cost of extra staff is needed to examine.

I would recommend two methods, one is to place a QC person at the seat arrival dock and check for defects before sending seats to the line, the other is to designate an area (in the overflow lot) for cars with seat defects.

In terms of the seat problem, the main cause is material flaws and missing parts. Having a QC person would be the easiest way to fix the problem quickly. If KFS sends the wrong replacement seats, the problems and the loopholes can be identified early and stopping them to going on the production line and then dropping them from there.