Acura TSX / Honda Accord CL. Manual — part 958

Fig. 140: Measuring The Voltage Between PCM Connector Terminals A20 & A8 Or A9

24. Turn the ignition switch OFF.

25. Jump the SCS line with the HDS.

26. Disconnect PCM connector A (31P).

27. Check for continuity between PCM connector terminal A20 and body ground.

Is there continuity?

YES: Repair short to ground in the wire between PCM connector terminal A20 and the
countershaft speed sensor, then go to step 29 .

NO: Check for loose or poor connections at PCM connector terminal A20. If the connection
is OK, update the PCM if it does not have the latest software, or substitute a known-good
PCM (see PCM UPDATING & SUBSTITUTION FOR TESTING ), then recheck. If the
symptom/indication goes away with a known-good PCM, replace the original PCM.

2004 Acura TSX

2004 AUTOMATIC TRANSMISSIONS Diagnosis - MCTA 5-Speed

Fig. 141: Checking For Continuity Between PCM Connector Terminal A20 & Body Ground

28. Measure the voltage between PCM connector terminals A18 and A8 or A9.

Is there about 5 V?

YES: Repair open in the wire between PCM connector terminal A18 and the countershaft
speed sensor, then go to step 29.

NO: Update the PCM if it does not have the latest software, or substitute a known-good
PCM (see PCM UPDATING & SUBSTITUTION FOR TESTING ), then recheck. If the

2004 Acura TSX

2004 AUTOMATIC TRANSMISSIONS Diagnosis - MCTA 5-Speed

symptom/indication goes away with a known-good PCM, replace the original PCM.

Fig. 142: Measuring The Voltage Between PCM Connector Terminals A18 & A8 Or A9

29. Clear the DTC with the HDS.

30. Test-drive the vehicle for several minutes under the same conditions as those indicated by the freeze data.

31. Check the OBD STATUS in DTCs MENU for a pass/fail test of code P0721.

Did the result indicate a pass?

YES: The problem has been corrected.

NO: Return to step 1 and recheck.

DTC P0722: PROBLEM IN COUNTERSHAFT SPEED SENSOR CIRCUIT (NO SIGNAL INPUT)

NOTE:

z

Record all freeze data and review General Troubleshooting Information
(see GENERAL TROUBLESHOOTING INFORMATION ) before you
troubleshoot.

z

This code is caused by an electrical circuit problem and cannot be caused
by a mechanical problem in the transmission.

2004 Acura TSX

2004 AUTOMATIC TRANSMISSIONS Diagnosis - MCTA 5-Speed

1. Clear the DTC with the HDS.

2. Raise the front of the vehicle, make sure it is securely supported, and allow the front wheels to rotate

freely.

3. Start the engine, drive the vehicle in the D position, and hold the vehicle at speeds over 30 mph (48 km/h)

for more than 10 seconds.

4. Check the OBD STATUS in DTCs MENU for a pass/fail test of code P0722.

Did the result indicate a fail?

YES: Go to step 5.

NO: Intermittent failure, the system is OK at this time. Check for poor connections or loose
terminals at the countershaft speed sensor and PCM. If the tester indicates NOT
COMPLETE, return to step 3 and recheck.

5. Turn the ignition switch OFF.

6. Jump the SCS line with the HDS.

7. Disconnect PCM connector A (31P) and countershaft speed sensor connector.

8. Check for continuity between PCM connector terminals A8 and body ground, and between A9 and body

ground.

Is there continuity?

YES: Go to step 9.

NO: Repair open in the wires between PCM connector terminals A8, A9 and ground (G101),
or repair poor ground (G 101), then go to step 30 .

2004 Acura TSX

2004 AUTOMATIC TRANSMISSIONS Diagnosis - MCTA 5-Speed