On-Vehicle Inspection [11/2016 - ]: Procedure

WARNING: This page is about a different car, the 2019 Toyota Highlander, 2018 Toyota Highlander, and 2017 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT CENTER EXHAUST PIPE ASSEMBLY (TWC: Rear Catalyst)

Inspect the exhaust flow control valve operation.

Remove the exhaust pipe gas control actuator sub-assembly.
Refer to REMOVAL [11/2016 - ] .

Using a screwdriver with its tip wrapped with protective tape, move the exhaust flow control valve from underneath the vehicle. Check that the valve moves smoothly.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Valve moves smoothly.

If the valve is stuck or does not move smoothly, replace the center exhaust pipe assembly (TWC: Rear Catalyst).
Refer to REMOVAL [11/2016 - ] .
Install the exhaust pipe gas control actuator sub-assembly.
Refer to REMOVAL [11/2016 - ] .

Inspect the exhaust pipe gas control actuator sub-assembly.

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.

Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

Powertrain > Engine and ECT > Data List

Tester Display
Coolant Temp

While checking the engine coolant temperature with the Techstream, check the operation of the exhaust pipe gas control actuator rod when the temperature rises.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard

Condition	Rod Operation
Cold (below approximately 71°C (160°F)) → Warmed up (approximately 80°C (176°F) or higher)	Exhaust pipe gas control actuator rod gradually extends smoothly as the temperature rises

If the exhaust pipe gas control actuator rod does not extend smoothly, replace the exhaust pipe gas control actuator sub-assembly.

Refer to REMOVAL [11/2016 - ] .

HINT:

After the engine has warmed up (the thermostat temperature is approximately 80°C (176°F) or higher), the exhaust pipe gas control actuator rod should be extended approximately 7.2 mm (0.283 in.) or more compared to when the engine is cold (the thermostat temperature is below 71°C (160°F)).

The coolant temperature shown in the Data List may slightly deviate from the thermostat temperature. This is because the Data List value indicates the temperature detected by the engine coolant temperature sensor, which is mounted on the engine, while the thermostat is positioned in the exhaust pipe gas control actuator sub-assembly.

If it is difficult to check the operation of the exhaust pipe gas control actuator rod, allow the engine to cool down until the coolant temperature matches the ambient temperature and then check the rod operation again.

Check for any cracks or damage on the exhaust pipe gas control actuator rod.
OK

No cracks or damage is found.

If any cracks or damage is found, replace the center exhaust pipe assembly (TWC: Rear Catalyst).

Refer to REMOVAL [11/2016 - ] .

INSPECT FOR ENGINE COOLANT LEAK FROM CENTER EXHAUST PIPE ASSEMBLY (TWC: Rear Catalyst)
WARNING:
Do not remove the radiator cap sub-assembly while the engine and radiator assembly are still hot. Pressurized hot engine coolant and steam may be released and cause serious burns.

NOTE:
Be sure to turn the A/C switch off before performing the following inspection.
1. Turn the power switch off. Check for engine coolant leaks from the center exhaust pipe assembly (TWC: Rear Catalyst) and heater hose around the temperature switch.
2. Add engine coolant to the radiator assembly and install a radiator cap tester.
3. Pump the radiator cap tester to 122 kPa (1.2 kgf/cm² , 18 psi), and then check that the pressure does not drop.
  If the pressure drops, check for leaks from the center exhaust pipe assembly (TWC: Rear Catalyst) and heater hose around the temperature switch.