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Circuit Test D21

NOTE: Perform this test only when service Codes 29, 39, 57, 59, 62, 67, 68, 69 or 89 are displayed.
Fig 1: AXOD Transaxle Circuits
G54822
NOTE: All components must be connected for this test and the following AXOD DRIVE CYCLE TEST must be performed:
  1. Continuous Memory Code 29 Displayed. Code 29 indicates insufficient input to the ECA from the Vehicle Speed Sensor (VSS). Possible causes for this fault are: faulty VSS, open or shorted circuit or faulty ECA. Perform AXOD DRIVE CYCLE TEST and return to this step. If Continuous Memory Code 29 is not displayed, fault cannot be duplicated at this time. If any other codes are present, return to QUICK TEST for instructions. If there are none, test is complete. If Continuous Memory Code 29 is displayed, go to next step.
  2. Checking Continuity of Vehicle Speed Sensor (VSS) Harness. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA and VSS disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 3 at the breakout box and VSS positive (+) circuit at harness connector. Measure resistance between test pin No. 6 and VSS negative (-) circuit at harness connector. If both readings are 5 ohms or more, repair open circuit(s) in VSS harness, then repeat step 1). If both readings are less than 5 ohms, go to next step.
  3. Checking VSS Harness For Shorts to Power or Ground. With key off, ECA and VSS disconnected, set DVOM on 200K-ohm scale. Measure resistance between test pin No. 3 and test pins No. 37, 40, and 6 at the breakout box. Measure resistance between test pin No. 6 and test pin No. 37 at the breakout box. If all readings are less than 10K ohms, repair short(s) in VSS harness, and repeat step 1). If all readings are more than 10K ohms, go to next step.
  4. Repeat Drive Cycle With Substitute VSS Installed. Substitute original VSS with a good known VSS. With ECA and VSS connected, perform AXOD DRIVE CYCLE TEST and return to this step. If Continuous Memory Code 29 is displayed, replace ECA then repeat step 1). If Code 29 is not displayed, replace original VSS then repeat QUICK TEST.
  5. Continuous Memory Code 69 Displayed. Perform AXOD DRIVE CYCLE TEST and return to this step. If Code 69 is not displayed, fault cannot be duplicated at this time. If any other codes are present, return to QUICK TEST for instructions. If no codes are displayed, test is complete. If Continuous Memory Code 69 is still displayed, go to next step.
  6. Checking Continuity of THS 3/2 Circuit. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA and AXOD harness disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 19 at the breakout box and THS 3/2 circuit at AXOD harness connector. If resistance is more than 5 ohms, repair open in THS 3/2 circuit then repeat step 5). If reading is 5 ohms or less, go to next step.
    Fig 2: AXOD Harness Connector (THS 3/2 Circuit)
    G108636
  7. Checking THS Circuit For Short to Power. With key off, breakout box installed, and ECA and AXOD harness disconnected, set DVOM on 200K-ohm scale. Measure resistance between test pin No. 19 and test pin No. 37. If reading is less than 10K ohms, repair short to power in THS 3/2 circuit, then repeat step 5). If reading is more than 10K ohms, go to next step.
  8. Checking ECA Verification. With key off and breakout box installed, connect ECA and AXOD harness. Install a jumper wire between test pins No. 19 and No. 40 at the breakout box. Perform KOEO SELF-TEST. If Code 62 or 69 is displayed, remove jumper wire and go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS. If Code 62 or 69 is not displayed, remove jumper wire, replace ECA, and then repeat step 5).
  9. Continuous Memory Code 59 Displayed. Perform AXOD DRIVE CYCLE TEST and return to this step. If Code 59 is not displayed, fault cannot be duplicated at this time. If any other codes are present, return to QUICK TEST for instructions. If none, test is complete. If Code 59 is displayed, go to next step.
  10. Checking Continuity of THS 4/3 Circuit. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA and AXOD harness disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 18 and THS 4/3 circuit at AXOD harness connector. If reading is more than 5 ohms, repair open in THS 4/3 harness, then repeat step 9). If reading is 5 ohms or less, go to next step.
    Fig 3: AXOD Harness Connector (THS 4/3 Circuit)
    G108637
  11. Checking THS 4/3 Circuit For Short to Power. With key off, breakout box installed, and ECA and AXOD harness disconnected, set DVOM on 200K-ohm scale. Measure resistance between pin No. 18 and test pin No. 37 at the breakout box. If reading is less than 10K ohms, repair short to power in THS 4/3 circuit, then repeat step 9). If reading is greater than 10K ohms, go to next step.
  12. ECA Verification. With key off and breakout box installed, connect ECA and AXOD harness. Install a jumper wire between test pins No. 18 and 40. Perform KOEO SELF-TEST. If Code 62 or 59 is displayed, remove jumper wire and go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS. If Code 59 or 62 is not displayed, remove jumper wire, replace ECA, and then repeat step 10).
  13. Continuous Memory Code 39 Displayed. Code 39 indicates AXOD converter by-pass clutch (lock-up) is not applying correctly. If Continuous Memory Code 59 is also present, go directly to step 9). Perform AXOD DRIVE CYCLE TEST then return to this step. If Continuous Memory Code 39 is still displayed, go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS. If Continuous Memory Code 39 is not displayed, fault cannot be duplicated at this time. If any other codes are present, return to QUICK TEST for instructions. If no codes are displayed, test is completed.
  14. Continuous Memory Code 57 Displayed. Code 57 indicates Neutral Pressure Switch (NPS) has failed in the open position. Possible causes for this fault are: open or short in NPS circuit, faulty ECA or faulty NPS. Perform AXOD DRIVE CYCLE TEST and then return to this step. If Continuous Memory Code 57 is not displayed, fault cannot be duplicated at this time. If any other codes are present, return to QUICK TEST for instructions. If no codes are displayed, test is completed. If Continuous Memory Code 57 is still displayed, go to next step.
  15. Checking Continuity of NPS Harness. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA and AXOD harness disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 30 and NPS circuit at AXOD harness connector. If resistance is more than 5 ohms, repair open in NPS circuit, then repeat step 14). If reading is 5 ohms or less, go to next step.
    Fig 4: AXOD Harness Connector (NPS Circuit)
    G108638
  16. Check NPS Circuit For Short to Power. With key off, install breakout box and disconnect ECA. Disconnect AXOD harness connector and set DVOM on 200K-scale. Measure resistance between test pin No. 30 and test pin No. 37 at the breakout box. If resistance is greater than 10K ohms, go to next step. If resistance is less than 10K ohms, repair short to power in NPS circuit, reconnect components and retest.
  17. ECA Verification. With key off, install breakout box and connect ECA. Ensure AXOD harness is connected. Jumper test pin No. 30 to test pin No. 40 at the breakout box. Run KOEO SELF-TEST. If Code 67 is present, remove breakout box and go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS. If Code 67 is not present, replace ECA, reconnect components and repeat step 14).
  18. Code 89 Displayed: Checking Continuity of VPWR Circuit. Code 89 indicates the Lock-Up Solenoid (LUS) signal indicates solenoid is always open or always closed. Possible causes for this fault are: open or shorted circuit, faulty ECA or faulty LUS. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA and AXOD harness disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 37 and VPWR circuit at AXOD harness connector. If reading is more than 5 ohms, repair open in VPWR circuit then repeat QUICK TEST. If reading is 5 ohms or less, go to next step.
    Fig 5: AXOD Harness Connector (VPWR Circuit)
    G108639
  19. Check Continuity of LUS Circuit. With key off, breakout box installed, and ECA and AXOD harness disconnected, set DVOM on 200 ohm scale. Measure resistance between test pin No. 53 and LUS circuit at AXOD harness connector. If reading is more than 5 ohms, repair open in LUS circuit and then repeat QUICK TEST. If reading is 5 ohms or less, go to next step.
    Fig 6: AXOD Harness Connector (LUS Circuit)
    G108640
  20. Checking LUS Circuit For Power to Ground. With key off, breakout box installed, and ECA and AXOD harness disconnected, set DVOM on 200K-ohm scale. Measure resistance between test pin No. 53 and test pins No. 37 and 40 at the breakout box. If both resistances are less than 10K ohms, repair shorts in LUS circuit. Repeat QUICK TEST. If Code 89 is still displayed, replace ECA and repeat QUICK TEST. If both readings are greater than 10K ohms, go to next step.
  21. Checking Total Circuit Resistance. With key off, breakout box installed, and ECA disconnected, connect AXOD harness. Set DVOM on 200K-ohm scale. Measure resistance between test pin No. 53 and test pin No. 57. If resistance is between 20 and 40 ohms, replace ECA and repeat QUICK TEST. If resistance is not between 20 and 40 ohms, go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS.
  22. Code 62: AXOD Harness Verification. Code 62 indicates 4/3 or 3/2 pressure switch signal indicates switch has failed in the closed position. Possible causes for this fault are: short in THS 4/3 or THS 3/2 circuit, faulty ECA, faulty THS 4/3 or 3/2 pressure switch. Turn key off and disconnect AXOD harness. Perform KOEO SELF-TEST and record codes. If Code 62 is still displayed, fault is in THS 4/3 circuit. Go to next step. If Code 62 is not displayed, remove test equipment and go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS.
  23. Checking THS 3/2 and 4/3 Circuits For Short to Ground. With key off, disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box and leave ECA disconnected. Leave AXOD harnesses disconnected. Set DVOM on 200K-ohm scale. Measure resistance between test pin No. 18 and test pins No. 40 and 60. Also measure resistance between test pin No. 19 and test pins No. 40 and 60. If all readings are less than 10K ohms, repair short(s) to ground. Repeat QUICK TEST. If all readings are greater than 10K ohms, replace ECA and repeat QUICK TEST.
  24. Code 59: AXOD Harness Verification. Code 59 indicates THS 4/3 pressure switch circuit has failed in the closed position. Possible causes for this fault are: short in THS 4/3 circuit, faulty ECA or faulty THS 4/3 pressure switch. Turn key off and disconnect AXOD Harness. Run KOEO SELF-TEST. If Code 59 is displayed, go to next step. If Code 59 is not displayed, go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS.
  25. Checking THS 4/3 Circuit For Short to Ground. With key off, disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leave ECA and AXOD harness connector disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 18 and test pins No. 40 and 60. If readings are greater than 10K ohms, remove breakout box, replace ECA and rerun QUICK TEST. If reading is less than 10K ohms, repair short in ECA and rerun QUICK TEST.
  26. Code 69: Checking AXOD Harness. Code 69 indicates THS 3/2 pressure switch circuit is failed in the closed position. Possible causes for this fault are: short in THS 3/2 circuit, faulty ECA or faulty 3/2 pressure switch. With key off, disconnect AXOD harness. Perform KOEO SELF-TEST. If Code 69 is still displayed, go to next step. If Code 69 is not displayed, go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS.
  27. Checking THS 3/2 Circuit For Short to Ground. With key off, disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box and leave ECA disconnected. Disconnect AXOD harness and set DVOM on 200K-ohm scale. Measure resistance between test pin No. 19 and test pins No. 40 and 60 at the breakout box. If all readings are less than 10K ohms, repair short to ground and repeat QUICK TEST. If all readings are greater than 10K ohms, replace ECA and rerun QUICK TEST.
  28. Code 67: Checking Voltage at NPS Input to ECA. Code 67 indicates that NPS circuit has failed closed or input to A/C clutch circuit is closed. Possible causes for this fault are: short in NPS circuit, or faulty ECA or NPS. With KOEO, disconnect ECA and inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box and reconnect ECA. Set DVOM on 20-volt scale. Measure voltage between test pins No. 30 and 46 at breakout box. If voltage is less than 4 volts, go to next step. If voltage is more than 4 volts, go to CIRCUIT TEST B13 , step 9).
  29. Checking NPS Harness Circuit For Shorts to Ground. Turn key off. Install breakout box and disconnect ECA and AXOD harness. Set DVOM on 200K-ohm scale. Measure resistance between test pin No. 30 and test pins No. 40 and 60 at the breakout box. If resistances are greater than 10K ohms, go to next step. If resistances are less than 10K ohms, repair ground short in NPS circuit and rerun QUICK TEST.
  30. Checking ECA. Turn key off and install breakout box. Reconnect ECA. Disconnect AXOD harness and run KOEO SELF-TEST. If Code 67 is displayed, replace ECA and rerun QUICK TEST. If Code 67 is not displayed, go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS.
  31. Code 68: Checking Continuity of TTS Harness Circuit. Code 68 indicates Transmission Temperature Switch (TTS) circuit is failed open. Possible causes for this fault are: open or shorted TTS circuit, faulty ECA or TTS. Turn key off and wait 10 seconds. Disconnect AXOD harness. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 44, at the breakout box, and TTS terminal of AXOD harness connector. If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open circuit in TTS circuit and road test vehicle to verify complaint.
    Fig 7: AXOD Harness Connector (TTS Circuit)
    G108642
  32. Checking TTS Harness For Short to Power or Ground. Turn key off and wait 10 seconds. Disconnect ECA and AXOD harness. Install breakout box and set DVOM on 200K-ohm scale. Measure resistance between test pin No. 44 and test pin No. 37 at the breakout box. Measure resistance between test pins No. 44 and 40 at the breakout box. If resistance is greater than 10K ohms, go to next step. If resistance is less than 10K ohms, repair short in TTS circuit and rerun QUICK TEST.
  33. Checking ECA Operation. With key off and breakout box installed, connect ECA and AXOD harness. Jumper between test pins No. 44 to No. 40 at the breakout box. Perform KOEO SELF-TEST. If Code 68 is still present, reconnect components and go to CIRCUIT TEST D24 , AXOD TRANSAXLE ELECTRICAL SYSTEM DIAGNOSIS. If complaint is still present, replace ECA, reconnect components and retest.
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