P1726

DTC P1726 TPS/APS LOSS OF SIGNAL





COMPONENT LOCATION

GENERAL DESCRIPTION
As a standard of judgement about a drivers acceleration degree, TPS signal is used at 2.0L gasoline engines or 2.7L gasoline engines. On both occasions, the signals are inputted to 4WD ECM from ECM (PCM: 2.0L gasoline engine) through CAN.
This signal is used as a standard signal which decides torque distribution together with a steering angle sensor signal, a wheel speed sensor signal and a brake signal.

DTC DESCRIPTION
The DTC will set when there is no TPS signal or the signal is out of range.





DTC DETECTING CONDITION





SCHEMATIC DIAGRAM





WAVEFORM INSPECTION

TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system may be caused from poor harness and terminals. These faults can 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. Has a problem been found?
YES Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO Go to the next procedure.

SIGNAL CIRCUIT INSPECTION
1. CAN Signal Inspection
1) IG KEY: ON, Engine: OFF.
2) 4WD ECM connector: connect.
3) Monitor signal waveform between terminal 4 and 5 of 4WD ECM harness connector.
4) Shift to N Range.
Specification: refer to "Waveform Inspection"
Is CAN Signal display near the specified value?
YES This may caused by intermittent fault. Verify data changeability by shaking the harness.
NO Inspect ground to short of CAN Low circuit.
^ Inspect open or short of CAN Low circuit.
^ Inspect ground to short of CAN High circuit.
^ Inspect open or short of CAN High circuit.
^ Inspect TPS (or APS) in the ECM side.
^ Check for ECM (or PCM) and replace it as necessary.
^ Check for 4WD ECM and replace it as necessary.
2. CAN Low open inspection
1) IG KEY OFF, ENG OFF
2) ECM and 4WD ECM connector: Disconnect.





3) Measure resistance between terminal 4 of 4WD ECM harness connector and terminal 6 or 37 of ECM harness connector.
Specification: Approximately 0 ohms
Is resistance display near the specified value?
YES Proceed next inspection procedure.
NO Repair open circuit of CAN Low comm. Line.
If problem is solved, go to the "Verification of Vehicle Repair".
3. CAN High open inspection
1) IG KEY OFF, ENG OFF
2) ECM and 4WD ECM connector: Disconnect.





3) Measure resistance between terminal 5 of 4WD ECM harness connector and terminal 10 (or 7 or 36) of ECM harness connector.
Specification: Approximately 0 Ohms
Is resistance display near the specified value?
YES Proceed next inspection procedure.
NO Repair open circuit of CAN High comm. Line.
If problem is solved, go to the "Verification of Vehicle Repair".

GROUND CIRCUIT INSPECTION
1. CAN Low circuit short to ground inspection
1) IG KEY ON, ENG OFF
2) ECM and 4WD ECM connector: Disconnect.





3) Measure resistance between terminal 4 of 4WD ECM harness connector and chassis ground.
Specification: Approximately 0 ohms
Is resistance display near the specified value?
YES Proceed next inspection procedure.
NO Repair ground to short circuit of CAN Low comm. Line.
If problem is solved, go to the "Verification of Vehicle Repair".
2. CAN High circuit short to ground inspection
2) IG KEY OFF, ENG OFF
2) ECM and 4WD ECM connector: Disconnect.





3) Measure resistance between terminal 5 of 4WD ECM harness connector and chassis ground.
Specification: Approximately 0 ohms
Is resistance display near the specified value?
YES Proceed next inspection procedure.
NO Repair ground to short circuit of CAN High comm. Line.
If problem is solved, go to the "Verification of Vehicle Repair".

VERIFICATION OF VEHICLE REPAIR
1. IG KEY ON, ENG OFF
2. ECK 4WD ECM connector: Connect.
3. Shift to N Range.
4. Clear the DTC with a scan tool.
5. Verify the malfunction relevant to TPS signal.
Does the scan tool display any DTC relevant to steering angle sensor center signal?
YES Go to the applicable troubleshooting procedure.
NO System OK.