Acura TSX / Honda Accord CL. Manual - part 951

REPLACEMENT ), then go to step 30 . 

Fig. 115: Measuring The Voltage Between PCM Connector Terminals C19 & A8 Or A9 

22. Shift to the P position. Start the engine, and let it idle.  

23. With the engine idling, measure the voltage between PCM connector terminals C19 and A8 or A9. 

Is there 1.5 V-3.5 V? 

YES: 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.  

NO: Replace the mainshaft speed sensor (see MAINSHAFT SPEED SENSOR 
REPLACEMENT ), then go to step 30 . 

 

2004 Acura TSX 

2004 AUTOMATIC TRANSMISSIONS Diagnosis - MCTA 5-Speed

  

 

Fig. 116: Measuring The Voltage Between PCM Connector Terminals C19 & A8 Or A9 

24. Measure the voltage between PCM connector terminals A21 and A8 or A9. 

Is there 4.75 V-5.25 V? 

YES: Repair open in the wire between PCM connector terminal A21 and the mainshaft speed 
sensor connector, then go to step 30 .  

NO: Go to step 25.  

 

2004 Acura TSX 

2004 AUTOMATIC TRANSMISSIONS Diagnosis - MCTA 5-Speed

  

 

Fig. 117: Measuring The Voltage Between PCM Connector Terminals A21 & A8 Or A9 

25. Turn the ignition switch OFF.  

26. Jump the SCS line with the HDS.  

27. Disconnect PCM connector A (31P).  

28. Check for continuity between PCM connector terminal A21 and body ground. 

Is there continuity? 

YES: Repair short to ground in the wire between PCM connector terminal A21 and the 
mainshaft speed sensor connector, then go to step 30 .  

NO: Check for loose or poor connections at PCM connector terminal A21. 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. 118: Checking For Continuity Between PCM Connector Terminal A21 & Body Ground 

29. Measure the voltage between PCM connector terminals C19 and A8 or A9. 

Is there about 5 V? 

YES: Repair open in the wire between PCM connector terminal C19 and the mainshaft speed 
sensor connector, then go to step 30.  

NO: Check for loose or poor connections at PCM connector terminal C19. 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 

 

2004 Acura TSX 

2004 AUTOMATIC TRANSMISSIONS Diagnosis - MCTA 5-Speed