P1721
DTC P1721 VEHICLE SPEED SENSOR MTRDescription
The vehicle speed sensor-MTR signal is transmitted from combination meter to TCM by CAN communication line. The signal functions as an auxiliary device to the revolution sensor when it is malfunctioning. The TCM will then use the vehicle speed sensor-MTR signal.
CONSULT-II Reference Value:
On Board Diagnosis Logic
^ This is not an OBD-II self-diagnostic item.
^ Diagnostic trouble code "P1721 VEH SPD SE/CIR-MTR" with CONSULT-II is detected when TCM does not receive the proper vehicle speed sensor MTR signal (input by CAN communication) from combination meter.
Possible Cause
^ Harness or connectors
(Sensor circuit is open or shorted.)
DTC Confirmation Procedure
CAUTION: Always drive vehicle at a safe speed.
NOTE: If "DTC Confirmation Procedure" has been previously performed, always turn ignition switch OFF and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
With CONSULT-II
1. Turn ignition switch ON.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-II.
3. Touch "START".
4. Start engine and maintain the following conditions for at least 5 consecutive seconds.
ACCELE POSI: 1.0/8 or less
VHCL/S SE-MTR: 30 km/h (17 MPH) or more
5. If DTC is detected, go to AT-140, "Diagnostic Procedure".
Diagnostic Procedure
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to AT-92, "SELF-DIAGNOSTIC RESULT MODE", AT-102, "Diagnostic Procedure without CONSULT-II".
Self-Diagnostic Result Mode
Is malfunction in the CAN communication indicated in the result?
YES >> Check CAN communication line. Refer to AT-104, "DTC U1000 CAN COMMUNICATION LINE". U1000
NO >> GO TO 2.
2. CHECK INPUT SIGNAL
With CONSULT-II
1. Start engine.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-II.
3. Drive vehicle and read out the value of "VHCL/S SE-MTR".
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. CHECK COMBINATION METERS
Check combination meters. Refer to DI-16, "Trouble Diagnosis". Combination Meters
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform AT-139, "DTC Confirmation Procedure".
OK or NG
OK >> INSPECTION END
NG >> GO TO 5.
5. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT-179, "MAIN POWER SUPPLY AND GROUND CIRCUIT".
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM.
NG >> Repair or replace damaged parts.