Electronic Throttle System (ETS)

ELECTRONIC THROTTLE SYSTEM (ETS)

Electronic Throttle System (ETS) Components:

COMPONENTS
ETC (Electronic Throttle Control) system is installed in throttle. ETC system controls the opening angle of throttle valve to operate throttle valve control, idle speed control, traction control, auto cruise control and so on. ECM receives accelerator position sensor signals (APS1, APS2) and calculates appropriate throttle opening angle which is used to control the throttle angle of throttle motor. Throttle position sensor integrated into throttle body assembly detects the throttle opening angle (TPS1, TPS2) and sends it to ECM for feedback control.

Circuit Diagram:

CIRCUIT DIAGRAM

Fail - Safe:

FAIL-SAFE
When throttle valve is stuck at 5" engine speed is limited at below 1500 rpm and vehicle speed at maximum 40-50 km/h.

ETC SYSTEM INITIALIZING
When ignition switch is turned from OFF to ON, ETC system learns the throttle angle as below procedures in 1.5 sec.
1. Throttle valve moves from limp-home position to close position.
2. And then, it opens to about 15" and moves to limp-home position.

REPLACING ETC BODY
After replacing ETC body or ECM, a new TPS adaptation has to be preformed as below procedures.







1. Clear the previous TPS adaptation value using Hi-Scan(Pro).
2. Turn the ignition switch off, and then turn it on.
3. Wait for 10 sec. until TPS adaptation finishes.

CAUTION: A new TPS adaptation has to be performed under environmental conditions as below.
- Battery voltage 10 V
- Air temperature 5.3 °C
- 5.3°C Coolant temperature 99.8 °C

INSPECTION

THROTTLE MOTOR
1. Disconnect the throttle body assembly connector.




2. Measure resistance as below.

Specification
Between pin 3 and 6 : 1.2 - 1.8 Ohms at 23 °C(73.4 °F)

3. Connect the throttle body assembly connector.

THROTTLE POSITION SENSOR (TPS)
1. Start engine and connect Hi-Scan (Pro) to data link connector.
2. Inspect TPS signal output with Hi-Scan (Pro) on condition as below.

Specification
<TPS1>
Idle : 0.3 - 0.7 V
Wide open throttle : 4.45 - 4.85 V
<TPS2>
Idle : 4.3 - 4.7 V
Wide open throttle : 0.1 5 - 0.55 V

3. Stop engine and disconnect throttle body assembly connector.




4. Measure resistance as below.

Specification
Between pin 1 and 2 : 0.88 - 1.63 Kohms

ACCELERATOR POSITION SENSOR (APS)
1. Disconnect APS connector and turn ignition switch on.




2. Measure voltage between the terminals 2 and 5 of APS connector as below.

Specification (APS1)
Not depressed : 0.58 - 0.93 V
Depressed fully : 3.85 - 4.35 V




3. Measure voltage between the terminals 3 and 6 of APS connector as below.

Specification (APS2)
Not depressed : 0.29 - 0.46 V
Depressed : fully : 1.93 - 2.18 V