P2173

P2173

Component Location:

General Description
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.

DTC Description
Comparing real intake air flow and the intake air flow calculated by ETS under detecting condition, if the difference of air flow more than threshold is detected for more than 3.9 sec., PCM sets P2173. MIL (Malfunction Indication Lamp) turns on when the malfunction lasts till 1 driving cycle.

DTC Detecting Condition:

Specification (Part 1):

Specification (Part 2):

Specification (Part 3):

Schematic Diagram:

Monitor Scantool Data
1. Connect scantool to DLC. (Data Link Connector)
2. Warm up the engine to normal operating temperature.
3. Monitor "TPS1&2, MAPS, MAFS" parameters on scantool






YES - Fault is intermittent caused by poor contact in Sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replaces necessary and go to "Verification of Vehicle Repair" procedure

NO - Go to "System Inspection" procedure.

System Inspection
1. Visual Inspection
1. Check the air hose between MAFS and throttle body is torn or installation.
2. Check deformation, crack or installation of throttle valve (body)
3. Has a problem been found?

YES - 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.

NO - 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 terminal 1 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 signal wave form displayed correctly?

YES - Go to "Verification of Vehicle Repair" procedure.

NO - 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. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code (DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions
4. Monitor that all readiness test have been verified as "Complete"
5. Are any DTCs present?

YES - Go to the applicable troubleshooting procedure.

NO - System is performing to specification at this time.