P1176
P1176 Throttle Actuator Control Motor Circuit/Open
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 unit, ETS-motor, Accelerator Position Sensor (APS),Throttle Position Sensor (TPS) and Limp home valve. The PCM sends 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. ETS motor's rotor rotates 780� from the the closed throttle valve to the wide open throttle valve and ETS motor controls the opening angle of throttle valve with 26 patterns; motor's rotor rotates 30� per one pattern.
DTC Description
DTC P1176 is set if the output voltage of ETS motor is lower than 6 V or the motor current is higher than 9A.
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 "Signal Circuit Inspection" procedure
Signal Circuit Inspection
Check for Short to Ground
1. Ignition "OFF"
2. Disconnect ETS motor and ETS unit connectors
3. Measure resistance between each
4. Is resistance within specifications?
YES
1) Go to "Component Inspection" procedure
NO
1) Check for short to ground in Signal 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
- Procedure of Initialization
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 1second to record the throttle motor position on the EEPROM.
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 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 DTC's present ?
YES
1) Go to the applicable troubleshooting procedure.
NO
1) System is performing to specification at this time.