DTC P0717: Problem in Input Shaft (Mainshaft) Speed Sensor Circuit (No Signal Input); DTC P0718: Input Shaft (Mainshaft) Speed Sensor Intermittent Failure

WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the GENERAL TROUBLESHOOTING INFORMATION
This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

Turn the ignition switch to ON (II).
Clear the DTC with the HDS.
Raise the vehicle on a lift, make sure it is securely supported, and allow the all four wheels to rotate freely.
Start the engine, disable the VSA by pressing the VSA OFF button, move the shift lever to D, and run the vehicle with the engine speed above 2, 000 rpm. Compare the Input Shaft (Mainshaft) Speed and the Output Shaft (Countershaft) Speed with the HDS in the A/T Data List. Slow down, and stop the wheels.
Are the speeds about the same?

YES -Intermittent failure, the system is OK at this time.

NO -Go to step 5.
Turn the ignition switch to LOCK (0).
Disconnect the input shaft (mainshaft) speed sensor connector.
Turn the ignition switch to ON (II).
Measure the voltage between input shaft (mainshaft) speed sensor connector terminal No. 1 and body ground.

Fig 1: Measuring Voltage Between Input Shaft (Mainshaft) Speed Sensor Connector Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?

YES -Go to step 9.

NO -Repair an open in the wire between PCM connector terminal C12 and the input shaft (mainshaft) speed sensor, then go to step 15.
Measure the voltage between input shaft (mainshaft) speed sensor connector terminal No. 2 and body ground.

Fig 2: Measuring Voltage Between Input Shaft (Mainshaft) Speed Sensor Connector Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?

YES -Go to step 10.

NO -Go to step 11.
Check for continuity between input shaft (mainshaft) speed sensor connector terminal No. 3 and body ground.

Fig 3: Checking For Continuity Between Input Shaft (Mainshaft) Speed Sensor Connector Terminal No. 3 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Replace the input shaft (mainshaft) speed sensor (see INPUT SHAFT (MAINSHAFT) SPEED SENSOR REPLACEMENT ), then go to step 15.

NO -Repair an open in the wire between the input shaft (mainshaft) speed sensor connector and PCM connector terminal C16, then go to step 15.
Turn the ignition switch to LOCK (0).
Jump the SCS line with the HDS.
Disconnect PCM connector B (49P).
Check for continuity between input shaft (mainshaft) speed sensor connector terminal No. 2 and body ground.

Fig 4: Checking For Continuity Between Input Shaft (Mainshaft) Speed Sensor Connector Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short to body ground in the wire between PCM connector terminal B37 and the input shaft (mainshaft) speed sensor, then go to step 15.

NO -Repair an open in the wire between PCM connector terminal B37 and the input shaft (mainshaft) speed sensor, then go to step 15.
Reconnect all connectors.
Turn the ignition switch to ON (II).
Clear the DTC with the HDS.
Start the engine, disable the VSA by pressing the VSA OFF button, move the shift lever to D, and run the vehicle with the engine speed above 2, 000 rpm. Compare the Input Shaft (Mainshaft) Speed and the Output Shaft (Countershaft) Speed with the HDS in the A/T Data List. Slow down, and stop the wheels.
Are the speeds about the same?

YES -Troubleshooting is complete.

NO -Replace the PCM (see PCM REPLACEMENT ).