P1739

P1739 GENERAL POS.ENCODER FAULT

Component Location






General Description

5 volts from TCCU is sent to MPS. In cases where the mode switch is changed; the shift motor is operates, and MPS contact point creates an ON/OFF signal. When 5 volts is received by the TCCU, it monitors operation of shift motor. There are 4 digital inputs for the shift motor position sensor. These 4 inputs are combined to make 16 possible Gray codes. The sense plate does not use all of these codes and non-used codes are considered invalid.






DTC Description

This trouble code is set when input value in case position encoder value is different from the pre-defined value in TCCU.

DTC Detecting Condition






Schematic Diagram






Signal Waveform






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 go to "Verification of Vehicle Repair" procedure
NO
1) Go to " Position Encoder Signal Inspection " procedure.

Position Encoder Signal Inspection
1. Engine : Idling.
2. TCCU connector : Connect.
3. Measure resistance between terminal B5,B15,B16,B18 of TCCU connector B and chassis ground .
4. Measure resistance between terminal B1 of TCCU connector B and chassis ground .
5. Change mode switch AUTO - LOW & LOW - AUTO and shift lever is positioned in N range.
A. Specification : Signal Waveform






CAUTION
The above value is only for reference. The actual value may differ from it according to various engine condition.

6. Is Position Encoder display near the specified value?
YES
1) Fault is intermittent caused by poor contact in the sensor's and/or TCCU's connector or was repaired and TCCU 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 " Shift Motor(HI-LOW) harness short circuit to ground inspection " procedure.

Position Encoder W/Harness Inspection
1. Ignition OFF.
2. TCCU connector : Disconnect.
3. Measure resistance between terminal B5,B15,B16,B18 of TCCU harness connector B and1,2,3,4of TRANSFER SOLENOID & MOTOR harness connector H-14 .
A. Specification : Approx. 8 Ohms






CAUTION
The above value is only for reference. The actual value may differ from it according to various engine condition.

4. Is resistance display near the specified value?
YES
1) Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
2) Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
1) Check for ground to short circuit of Position Encoder signal harness.
2) Repair as necessary and then 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 scan tool and select "Diagnostic Trouble Codes(DTCs)" mode
2. Using scantool, Clear DTC.
3. Operate the vehicle within DTC Enable conditions in General information.
4. Are any DTCs present ?
YES
1) Go to the applicable troubleshooting procedure.
NO
1) System is performing to specification at this time.