FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P1172



P1172 Improper Motor Current - ETS

Component Location





General Description

The ETS (Electronic Throttle System) is the throttle body whose throttle angle is controlled by control module. It consists of ETS throttle valve target opening value to ETS unit after calculating from signals such as APS and other input values. The ETS unit controls ETS motor to meet PCM's throttle valve target opening value. TPS is mounted on throttle body assembly and detects the opening angle of the throttle valve. The TPS is a variable resistor (potentiometer) whose characteristic is that the resistance changes according to throttle position angle. TPS 1 and TPS 2 signals are used to monitor PCM's throttle valve target opening values activation between PCM and ETS unit. TPS1's output signal is the main signal to calculate the target value for opening throttle valve and to decide whether TPS2 is normal or not. TPS2's output signal is the sub signal to decide whether TPS1 is normal or not. And if TPS1's signal is abnormal, TPS2's output signal is used as the main signal.

DTC Description

DTC P1172 is set if the difference between actual ETS motor current and target ETS motor current is higher than 3A.

DTC Detecting Condition





Specification





Schematic Diagram





Signal Waveform






Monitor Scantool Data

1. Connect scantool to Data Link Connector (DLC).

2. Ignition "ON" & Engine "OFF".

3. Select "ACTUATION TEST" on scantool.

4. Using the scantool, operate ETS motor by force





5. Does the ETS motor operate well?

YES
1) Fault is intermittent caused by poor contact in the related sensor's and/or ETS unit 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 replace as necessary and then go to "Verification of Vehicle Repair" procedure.

NO

1) Go to "W/Harness Inspection" procedure.


Terminal and Connector Inspection

1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

3. Has a problem been found?

YES

1) Repair as necessary and then go to "Verification of Vehicle Repair" procedure

NO

1) Go to "Control Circuit Inspection" procedure.

Control Circuit Inspection

Check for Signal Circuit

1. Ignition "OFF"

2. Disconnect ETS motor and ETS unit connectors

3. Measure resistance between terminals "1" of ETS unit harness connector and "2" of ETS motor harness connector.

4. Measure resistance between terminals "15" of ETS unit harness connector and "1" of ETS motor harness connector.

5. Measure resistance between terminals "14" of ETS unit harness connector and "3" of ETS motor harness connector.

A. Specification: Approx. 0 ohm





6. Is resistance within specifications?

YES

1) Go to "Component Inspection" procedure

NO

1) Check for open or high resistance of wire in control harness. Repair as necessary and go to "Verification of\ Vehicle Repair" procedure.


Component Inspection

Check ETS Motor

1. Ignition "OFF".

2. Disconnect ETS motor connector

3. Measure resistance between terminals "1" and "2" of the ETS motor connector. (Component side)

4. Measure resistance between terminals "1" and "3" of the ETS motor connector. (Component side)

5. Measure resistance between terminals "2" and "3" of the ETS motor connector. (Component side)

A. Specification

1) Approx. 0.6 ~ 1.5 ohms ("1" to "2")





2) Approx. 0.6 ~ 1.5 ohms ("1" to "3")





3) Approx. 0.6 ~ 1.5 ohms ("2" to "3")





- Difference between each resistance should be less than 0.5O

6. Is the ETS motor resistance within specifications?

YES

1) Substitute with a known-good ETS unit and check for proper operation. If the problem is corrected, replace ETS unit and then go to "Verification of Vehicle Repair" procedure. If ETS unit needs to be replaced, do initialization after it is replaced.

NO

1) Check ETS motor for contamination,deterioration, or damage. Substitute with a known-good ETS motor and check for proper operation. If the problem is corrected, replace ETS motor and then do initialization. And go to "Verification of Vehicle Repair" procedure.

1. Erase the trouble codes on PCM

2. Turn the ignition key on less than 1second and turn it off (Do not start the engine)

3. Turn the ignition key off and keep this condition until the main relay is turned off. (It will takes 10 second)

4. Turn ignition key on more than 1 second to record the throttle motor position on the EEPROM.


Verification of Vehicle Repair

1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code (DTC) which has been diagnosed

2. Using a Scantool, Clear DTC.

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

1) Go to the applicable troubleshooting procedure.

NO

1) System is performing to specification at this time.