P0721, P0722, P0723 (A/T)

NOTE:  Before you troubleshoot, review the General Troubleshooting Information .

DTC (A/T)

1. Problem verification

   -1. Raise the vehicle on a lift. Make sure it is securely supported, and allow all four wheels to rotate freely.

   -2. Turn the vehicle to the ON mode.

   -3. Clear the DTC with the HDS.

   -4. Start the engine, disable the VSA .

   -5. Run the vehicle at speeds over 13 mph (21 km/h), and compare the parameters below with the HDS.

   Signal	Current conditions
   	Values	Unit
   Output Shaft (CounterShaft) Speed
   Input Shaft (Mainshaft) Speed

   Are the speeds about the same?

   YES 

   Intermittent failure, the system is OK at this time. Check for poor connections and loose terminals between the countershaft speed sensor and the TCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

   NO 

   The failure is duplicated. Go to step 2.

2. Determine possible failure area (NC line, others)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the following connector.

   Countershaft speed sensor 3P connector

   -3. Turn the vehicle to the ON mode.

   -4. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode
   	Countershaft speed sensor 3P connector: disconnected
   Test point 1	Countershaft speed sensor 3P connector (female terminals) No. 3:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there about 5 V?

   YES 

   Go to step 3.

   NO 

   Go to step 5.

3. Open wire check (VCC3 line)

   -1. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode
   	Countershaft speed sensor 3P connector: disconnected

   Test point 1	Countershaft speed sensor 3P connector (female terminals) No. 1:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there about 5 V?

   YES 

   The VCC3 wire is OK. Go to step 4.

   NO 

   Repair an open in the VCC3 wire between the countershaft speed sensor and the TCM.

4. Open wire check (SG3 line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the following connector.

   TCM connector A (23P)

   -3. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Countershaft speed sensor 3P connector: disconnected
   	TCM connector A (23P): disconnected
   Test point 1	Countershaft speed sensor 3P connector (female terminals) No. 2:
   Test point 2	TCM connector A (23P) No. 16

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The SG3 wire is OK. Replace the countershaft speed sensor .

   NO 

   Repair an open in the SG3 wire between the countershaft speed sensor and the TCM.

5. Shorted wire check (NC line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the following connector.

   TCM connector A (23P)

   -3. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Countershaft speed sensor 3P connector: disconnected
   	TCM connector A (23P): disconnected
   Test point 1	Countershaft speed sensor 3P connector (female terminals) No. 3:
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   Repair a short to ground in the NC wire between the countershaft speed sensor and the TCM.

   NO 

   The NC wire is not short. Go to step 6.

6. Open wire check (NC line)

   -1. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Countershaft speed sensor 3P connector: disconnected
   	TCM connector A (23P): disconnected
   Test point 1	Countershaft speed sensor 3P connector (female terminals) No. 3:
   Test point 2	TCM connector A (23P) No. 2

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The NC wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good TCM , then recheck. If this DTC goes away and the TCM was substituted, replace the original TCM .

   NO 

   Repair an open in the NC wire between the countershaft speed sensor and the TCM.