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DTC Troubleshooting: P0718 (15)

DTC P0718:
 Input Shaft (Mainshaft) Speed Sensor (Intermittent Failure)
NOTE:
  • Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review General Troubleshooting Information.
  • This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
  1. Clear the DTC with the HDS.
  1. Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears at speeds over 20 km/h (12 mph). Slow down and stop the wheels.
  1. Monitor the OBD status for P0718 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the HDS indicate FAILED?
YES -
Go to Step 4 .
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the input shaft (mainshaft) speed sensor and the PCM. If the HDS indicates NOT COMPLETED, return to Step 2 and recheck.
  1. Turn the ignition switch to LOCK (0).
  1. Disconnect the input shaft (mainshaft) speed sensor connector, and inspect the connector and connector terminals to be sure they are making good contact.
Are the connector terminals OK?
YES -
Go to Step 6 .
NO -
Repair the connector terminals, then go to Step 6 .
  1. Connect the input shaft (mainshaft) speed sensor connector.
  1. Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears at speeds over 20 km/h (12 mph). Slow down and stop the wheels.
  1. Monitor the OBD status for P0718 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the HDS indicate FAILED?
YES -
Go to Step 9 .
NO -
Troubleshooting is complete. If the HDS indicates NOT COMPLETED, return to Step 7 and recheck.■
  1. Turn the ignition switch to LOCK (0).
  1. Jump the SCS line with the HDS.
  1. Disconnect PCM connector C (49P).
  1. Check for continuity between PCM connector terminals C44 and body ground, and between C48 and body ground.
Is there continuity?
YES -
Go to Step 13 .
NO -
Repair open in the wires between PCM connector terminals C44, C48 and ground (G101), or repair poor ground (G101), then go to Step 37 .
  1. Connect PCM connector C (49P).
  1. Disconnect the input shaft (mainshaft) speed sensor connector.
  1. Turn the ignition switch to ON (II).

  1. Measure the voltage between input shaft (mainshaft) speed sensor connector terminal No. 1 and body ground.
Is there about 5 V?
YES -
Go to Step 17 .
NO -
Go to Step 28 .
  1. Turn the ignition switch to LOCK (0).
  1. Jump the SCS line with the HDS.
  1. Disconnect PCM connector B (49P).

  1. Check for continuity between input shaft (mainshaft) speed sensor connector terminal No. 2 and body ground.
Is there continuity?
YES -
Repair short in the wire between PCM connector terminal B18 and the input shaft (mainshaft) speed sensor connector, then go to Step 37 .
NO -
Go to Step 21 .
  1. Connect PCM connector B (49P).
  1. Turn the ignition switch to ON (II).

  1. Measure the voltage between input shaft (mainshaft) speed sensor connector terminal No. 2 and body ground.
Is there about 5 V?
YES -
NO -
Go to Step 24 .
  1. Turn the ignition switch to LOCK (0).
  1. Jump the SCS line with the HDS.
  1. Disconnect PCM connector B (49P).

  1. Check for continuity between PCM connector terminal B18 and input shaft (mainshaft) speed sensor connector terminal No. 2.
Is there continuity?
YES -
Go to Step 32 .
NO -
Repair open in the wire between PCM connector terminal B18 and the input shaft (mainshaft) speed sensor, then go to Step 37 .
  1. Turn the ignition switch to LOCK (0).
  1. Jump the SCS line with the HDS.
  1. Disconnect PCM connector B (49P).

  1. Check for continuity between PCM connector terminal B19 and input shaft (mainshaft) speed sensor connector terminal No. 1.
Is there continuity?
YES -
Go to Step 32 .
NO -
Repair open in the wire between PCM connector terminal B19 and the input shaft (mainshaft) speed sensor, then go to Step 37 .
  1. Reconnect all connectors.
  1. Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears at speeds over 20 km/h (12 mph). Slow down and stop the wheels.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0718 indicated?
YES -
If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to Step 1 .
NO -
Go to Step 36 .
  1. Monitor the OBD status for P0718 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the HDS indicate PASSED?
YES -
If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other DTCs were indicated on Step 35 , go to the indicated DTC's troubleshooting.■
NO -
Check for poor connections and loose terminals at the input shaft (mainshaft) speed sensor and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to Step 1 . If the HDS indicates NOT COMPLETED, return to Step 34 and recheck.
  1. Reconnect all connectors.
  1. Clear the DTC with the HDS.
  1. Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears at speeds over 20 km/h (12 mph). Slow down and stop the wheels.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0718 indicated?
YES -
Check for poor connections and loose terminals at the input shaft (mainshaft) speed sensor and the PCM, then go to Step 1 .
NO -
Go to Step 41 .
  1. Monitor the OBD status for P0718 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the HDS indicate PASSED?
YES -
Troubleshooting is complete. If any other DTCs were indicated on Step 40 , go to the indicated DTC's troubleshooting.■
NO -
Check for poor connections and loose terminals at the input shaft (mainshaft) speed sensor and the PCM, then go to Step 1 . If the HDS indicates NOT COMPLETED, return to Step 39 and recheck.