Don’t fear Asian vehicles! Since many companies already share parts and technology, you will notice that Asian vehicle are not that much different than domestic vehicles. Just like any other vehicle that comes into your shop with a problem, you need a game plan on how you’re going to address the problem.
2010 Toyota 4Runner
Our first vehicle is a 2010 Toyota 4Runner 1GR-FE with 128k that came in with the ABS light illuminated and the owner complaint of a braking issue. We started our diagnosis with a Q&A of the owner, followed by a short test drive and a visual inspection before connecting our scan tool.
After we connected the Toyota TechStream scan tool (Figure 1) we found the following DTCs; C1404 (Open or Short in Rear Speed Sensor LH Circuit), C1408 (Open or Short in Rear Speed Sensor LH Circuit) and C1416 (Open in the Sensor Signal Circuit of a Malfunction area occur 255 times or more). Our next step was to take a look at the DTC supporting information - Freeze Frame. As you can see from the Freeze Frame data (Figure 2), the Left Rear wheel speed was recorded moving at 0 mph, while the other wheels were displaying 26 to 27 mph.
With the test drive confirming that the circuit had a problem, my lead technician (Bill) checked the wiring to make sure there were no connection problems. After the wiring checked out, the next step was to call the 4Runner owner and recommend that both rear wheel speed sensors be replaced. Take notice, that we did not use a labscope on this problem since Toyota service information had specific testing of the circuit that would confirm the problem without using any other tool besides the Toyota Techstream. Why take out the backhoe when a shovel will do the job? We need to remember that we sell our time to the customer, so we need to diagnosis the problem in the easiest and most efficient way.