The Electronic Throttle
Control(ETC) system is made of the components throttle body, Throttle
Position Sensor(TPS)1&2 and Accelerator Position Sensor(APS) 1&2.
The throttle body contains the actuator, the throttle plate and the
throttle position sensor (potentiometer), which are integrated in one
housing. The actuator consists of a DC motor with a two-stage gear. The
opening angle of the throttle valve is detected by the throttle position
sensor which is mounted on the throttle body. And it provides feedback to
the PCM to control the throttle motor in order to control the throttle
valve opening angle properly in response to the driving
condition.
Comparing real intake
air flow and the intake air flow calculated by ETS under detecting
condition, if the air flow more than threshold value is detected for more
than 19 sec., PCM sets P2173. And then MIL(Malfunction Indication Lamp)
turns on.
Item
|
Detecting
Condition
|
Possible Cause
|
DTC Strategy
|
| •
|
Monitor the measured engine airflow and
the estimated airflow | |
| •
|
Air Leakage between TPS and
MAFS |
| •
|
Faulty throttle body or intake
manifold |
|
EnableConditions
|
|
Threshold
|
Case
1
|
| •
|
MAPS reading - ETC estimated airflow
> 9 g/s | |
Case
2
|
| •
|
MAFS reading - ETC estimated airflow
> 7g/s | |
Diagnosis Time
|
| •
|
Contineous
(Within 20
sec.) | |
MIL On Condition
|
|
MAFS
Air Flow (kg/h)
|
Frequency (Hz)
|
12.6
|
2617.0
|
18.0
|
2958.0
|
23.4
|
3241.0
|
32.4
|
3653.0
|
43.2
|
4024.0
|
57.6
|
4399.0
|
72.0
|
4704.0
|
108.0
|
5329.0
|
144.0
|
5897.0
|
198.0
|
6553.0
|
270.0
|
7240.0
|
360.0
|
7957.0
|
486.0
|
8738.0
|
666.0
|
9644.0
|
900.0
|
10590.0
|
TPS
Throttle opening
(°)
|
Output voltage(V)
[Vref=5.0V]
|
TPS1
|
TPS2
|
0°
|
0.0V
|
5.0V
|
10°
|
0.5V
|
4.5V
|
V20°
|
0.9V
|
4.1V
|
30°
|
1.4V
|
3.6V
|
40°
|
1.8V
|
3.2V
|
50°
|
2.3V
|
2.7V
|
60°
|
2.7V
|
2.3V
|
70°
|
3.2V
|
1.8V
|
80°
|
3.6V
|
1.4V
|
90°
|
4.1V
|
0.9V
|
100°
|
4.5V
|
0.5V
|
110°
|
5.0V
|
0.0V
|
MAPS
Pressure(kPa)
|
Output
voltage(V)
|
20.0kPa
|
0.79V
|
35kPa
|
1.382V
|
46.66kPa
|
1.84V
|
60kPa
|
2.369V
|
90kPa
|
3.75V
|
101.32kPa
|
4.00V
|
| 1. |
Check DTC Status
| (1) |
Connect scantool to Data Link
Connector(DLC). |
| (3) |
Select "DTC" button, and then Press "DTC
Status" to check DTC's information from the DTCs
menu. |
| (4) |
Read "DTC Status"
parameter.
|
| (5) |
Is parameter displayed "Present
fault"?
|
|
▶ Go
to "System Inspection" procedure.
|
|
|
▶
Fault is intermittent caused by poor contact in the
sensor's and/or PCM's connector or was repaired and PCM
memory was not cleared. Thoroughly check connectors for
looseness, poor connection, ending, corrosion,
contamination, deterioration, or damage. Repair or
replace as necessary and go to "Verification of Vehicle
Repair"
procedure.
|
| |
| 1. |
Visual Inspection
| (1) |
Check the air hose between MAFS and
throttle body is torn or
installation. |
| (2) |
Check deforamtion, crack or installation
of throttle valve(body) |
| (3) |
Has a problem been found ?
|
|
▶
Substitute with a known-good Air hose or throttle body
and check for proper operation.
If the problem is corrected,replace air hose
or throttle body and then go to "Verification of Vehicle
Repair" procedure.
|
|
|
▶ Go
to "Check MAFS" as
follows.
|
| |
| 2. |
Check MAFS
| (1) |
IG "OFF" and install a
scantool |
| (2) |
ENG "ON" and monitor "MAFS" data on the
service data. |
| (3) |
Monitor signal waveform at signal
terminal of MAFS with scantool.
Specification :
Signal waveform will be displayed as
follows.
(Be aware that the signal of MAFS
is not voltage display but frequency
display.)
|
|
| (4) |
Are both service data and signalwave
form dispayed correctly ?
|
|
▶ Go
to "Verification of Vehicle Repair"
procedure.
|
|
|
▶
Substitute with a known - good MAFS and check for proper
operation. If the problem is corrected, replace MAFS and
go to "Verification of Vehicle Repair"
procedure.
|
| |
| Verification Of Vehicle
Repair |
After a repair, it is
essential to verify that the fault has been corrected.
| 1. |
Connect scantool and select "DTC"
button. |
| 2. |
Press "DTC Status" button and confirm that
"DTC Readiness Flag" indicates "Completed". If not, drive the
vehicle within conditions noted in the freeze frame data or enable
conditions |
| 3. |
Read "DTC Status"
parameter |
| 4. |
Is parameter displayed "History(Not Present)
fault"?
|
|
▶ System
performing to specification at this time. Clear the
DTC
|
|
|
▶ Go to the
applicable troubleshooting
procedure.
|
|
