DESCRIPTION The idling speed is controlled by the Electronic Throttle Control System (ETCS). The ETCS is comprised of a throttle actuator, which operates the throttle valve, and a throttle position sensor, which detects the opening amount of the throttle valve. The ECM controls the throttle actuator to adjust the throttle valve opening amount so that the idling speed is maintained at the target idling speed.
HINT:
MONITOR DESCRIPTION If there are deposits in the throttle valve, a decrease in the ISC flow rate may cause engine stall and unstable idling. Therefore, the necessary ISC flow rate for idling is maintained using the ISC learned value and feedback. The ECM stores this DTC if the ISC learned value approaches its limit. The ECM begins monitoring for the DTC detection conditions when the following preconditions are met; 1) the manifold absolute pressure sensor is normal; 2) atmospheric pressure is 85 kPa (638 mmHg) or higher; 3) the vehicle has been driven at a speed of 30 km/h (19 mph) or more at least once; and 4) the engine coolant temperature is 45°C (113°F) or less at engine start, the engine is warmed up and conditions for ISC learning are met, or the ignition switch has been turned ON (include engine running) for 1 hour or more, the engine is warmed up and conditions for ISC learning are met. CAUTION / NOTICE / HINT HINT:
PROCEDURE
(a) Connect the Techstream to the DLC3. (b) Turn the ignition switch ON. (c) Turn the Techstream on. (d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes. (e) Read the DTCs.
HINT: If any DTCs other than P2109 are output, troubleshoot those DTCs first.
(a) Connect the Techstream to the DLC3. (b) Turn the ignition switch to ON. (c) Using the Techstream, check "ISC Learning Value" in the freeze frame data (See page ). HINT: Be sure to confirm "ISC Learning Value" in the freeze frame data as it is used when confirming whether the malfunction has been successfully repaired.
(a) Clean off any deposits from the inside of the throttle with motor body assembly. (1) Push open the throttle valve and wipe off any carbon from the valve and bore using a cloth soaked in non-residue solvent. NOTICE:
HINT: If the throttle valve does not open smoothly, replace the throttle with motor body assembly.
(a) Perform "Inspection After Repair" after cleaning or replacing the throttle with motor body assembly (See page ). (b) Enter the following menus: Powertrain / Engine and ECT / Data List / ISC Learning Value. (c) Read the value. OK: The value is half of "ISC Learning Value" recorded in the freeze frame data or less. HINT: Perform "Inspection After Repair" after replacing the throttle with motor body assembly (See page ).
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Toyota Tundra Service Manual > Navigation System: Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter
DESCRIPTION The stereo component amplifier assembly receives a vehicle speed signal from the combination meter assembly to control the ASL function. HINT: A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter assembly. The signal is changed to a pulse signal at the ...