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Test D25 - E4OD Trans

NOTE: You should perform this test when Codes 26, 47, 56, 66, 67, 91, 92, 93, 94, 97, 98 and 99 are displayed during KOEO SELF-TEST, Codes 26 and 65 are displayed during KOER SELF-TEST, or Codes 29, 49, 56, 59, 62, 66, 69 and 99 are displayed during CONTINUOUS MONITOR MODE testing or when directed here during DIAGNOSIS BY SYMPTOM  tests. This circuit test is intended to diagnose only the following: harness circuits, CCC, CCS, 4X4 LOW, EPC, OCIL, OCS, SS1, SS2, SIGNRTN, TOT, MLP, VPWR and ECA. The Transmission Solenoid Assembly (7G391) and Manual Lever Position (MLP) sensor (7F293) are not diagnosed in this circuit test as they are not controlled by the ECA.
Fig 1: E4OD & MLP Harness Schematic
G120776
Fig 2: 4X4 Low & OD Cancel Harness Schematic
G120777
Fig 3: E4OD Pinpoint Test Schematic
G120778
  1. Code 67: Check Resistance Through MLP Sensor. Code 67 indicates that total resistance in the MLP sensor is out of Self-Test range when the selector lever is in "P" (correct range is 3770-4607 ohms). Possible causes for this fault are: faulty MLP sensor, open or shorted harness, faulty ECA. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector and inspect for corroded or damaged pins. Service or repair as necessary. Install breakout box, leaving ECA disconnected. Set DVOM on 10k-ohm scale. With KOEO, measure resistance between test pins No. 30 and 46 at the breakout box while moving the selector from "P" to "L" and back to "P". Record specifications and compare to specification table. If resistance is within specification, go to step 3). If not, go to next step.
    MLP RESISTANCE SPECIFICATIONS

    Gear Position Min. Ohms Max. Ohms
    "P" 3770 4607
    "R" 1304 1593
    "N" 660 807
    "D" 361 442
    "2" 190 232
    "1" 78 95
  2. Checking Continuity of MLP Harness. Ensure key is off and MLP sensor is disconnected from harness. Use a mirror to inspect ends of transmission harness connector at MLP sensor for damage or corrosion. Repair as necessary. Install breakout box, leaving ECA disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 30 at the breakout box and corresponding pin at the MLP sensor vehicle harness connector. Measure resistance between test pin No. 46 at the breakout box and corresponding pin at the MLP sensor vehicle harness connector. If both resistances are less than 5 ohms, go to next step. If not, repair open circuit, remove breakout box, reconnect components and rerun QUICK TEST.
  3. Check MLP Harness For Short To Power Or Ground. Turn key off. Ensure MLP sensor harness is disconnected. Install breakout box leaving ECA disconnected. Set DVOM on 200k-ohm scale. Measure resistance between test pin No. 30 and test pins No. 37 and 57 at the breakout box. Measure resistance between test pin No. 30 and test pins No. 40, 46 and 60 at the breakout box. Measure resistance between test pin No. 30 at the breakout box and chassis ground. If all resistances are greater than 10k ohms, go to next step. If not, repair short circuits, remove breakout box, reconnect components and rerun QUICK TEST.
  4. Checking ECA Output Voltage. Ensure key is off. Disconnect MLP sensor from harness. Install breakout box and connect ECA. With KOEO, set DVOM on 20-volt scale. Measure voltage between test pins No. 30 and 46 at the breakout box. If voltage is 4.75-5.25 volts, service or adjust MLP sensor. If not, replace ECA, reconnect components and rerun QUICK TEST.
  5. Code 47, 65 or 97: Verify Self-Test Mode. Code 47 indicates 4X4 LOW selector lever is not in 4X2 or 4X4 High position during KOEO Self-Test. This condition may be accompanied by an early shift in the 4X4 High range. Code 65 indicates that Overdrive Cancel Switch (OCS) is not cycled between the engine I.D. code and "Goose Test" in the KOER Self-Test. Code 97 indicates an Overdrive Cancel Light (OCL) fault during KOER Self-Test. Possible causes for this fault are: faulty 4X4 LOW switch, faulty OCS switch, burned out bulb, open harness, shorted harness or faulty ECA. Rerun QUICK TEST. If none of the above codes are present, fault cannot be duplicated at this time, testing is complete. If Code 97 is present, go to step 7). If any other codes are present, go to next step.
  6. Cycle 4X4 LOW Or Overdrive Cancel Switch Circuit. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector and inspect for corroded or damaged pins. Service or repair as necessary. Install breakout box, leaving ECA disconnected. With KOEO, set DVOM on 20-volt scale. For 4X4 LOW Circuit, measure voltage between test pin No. 12 and test pins No. 40 and 60 at the breakout box while cycling the Overdrive Cancel Switch (OCS). Move transfer case lever between 4X4 and 4X2 positions several times. For Overdrive Cancel Switch (OCS) Circuit, measure voltage between test pin No. 41 and test pins No. 40 and 60 at the breakout box while cycling the Overdrive Cancel Switch. Toggle the switch on the dash several times. If voltage cycles, remove breakout box. Replace ECA and rerun QUICK TEST. If voltage does not cycle, go to step 9) for driveability faults or next step for other faults.
  7. Checking Circuits For Shorts To Ground. Ensure key is off, breakout box is installed and ECA is disconnected. Set DVOM on 200k ohm scale. For 4X4 LOW Circuit, disconnect 4X4 LOW switch. Measure resistance between test pin No. 12 and test pins No. 40 and 60 at the breakout box. For Overdrive Cancel Switch (OCS) Circuit, disconnect Overdrive Cancel Switch. Measure resistance between test pin No. 41 and test pins No. 40 and 60 at the breakout box. If resistance(s) is greater than 10k ohms, go to step 10) for Code 47 or 65. Go to next step for Code 97. If resistance is not greater than 10k ohms, for Code 47, repair short circuit and rerun KOEO Self-Test; for Code 65, repair short circuit and rerun KOER Self-Test, if Code 65 is still present, go to step 9). For Code 97, repair short circuit and rerun KOEO Self-Test.
  8. Checking Key Power Through OCIL Circuit. With KOEO, ensure breakout box is installed and ECA is disconnected. Set DVOM on 20-volt scale. Measure voltage between test pin No. 32 and test pins No. 40 and 60 at the breakout box. If voltage is greater than 10.5 volts, remove breakout box, replace ECA and rerun QUICK TEST. If not, go to next step.
  9. Checking Continuity Of LED Harness (4X4 LOW Or Overdrive Cancel). With KOEO, disconnect ECA 60-pin connector and inspect for corroded or damaged pins. Service or repair as necessary. Install breakout box, leaving ECA disconnected. Disconnect 4X4 LOW or Overdrive Cancel Switch. Set DVOM on 200-ohm scale. For 4X4 LOW Circuit, measure resistance between Key Power Circuit at the fuse panel (+ probe) and test pin No. 12 (- probe) at the breakout box. For OCS-OCIL Circuit, measure resistance between Key Power Circuit at the fuse panel (+ probe) and test pin No. 32 (- probe) at the breakout box.
    Fig 4: Fuse Panel
    G120779

    If resistance is less than 5 ohms, go to next step. If not, check for a faulty indicator bulb (4X4 LOW LED or OCIL) or defective fuse in fuse panel. If fuse is okay, repair open circuit, remove breakout box and reconnect ECA. Rerun QUICK TEST.

  10. Checking Continuity Of The 4X4 LOW Or Overdrive Cancel Switch Harness. With key off, breakout box installed and ECA disconnected, disconnect appropriate switch. Set DVOM on 200 ohm scale. For 4X4 LOW Circuit, measure resistance between test pin No. 12 at the breakout box and 4X4 LOW circuit at the 4X4 LOW switch vehicle harness.
    Fig 5: 4X4 LOW Circuit
    G120780

    For OCS-OCIL Circuit, measure the resistance between KEY PWR at the fuse panel (shown in step 14), ohmmeter positive lead) and the power side of the OCS harness connector (ohmmeter negative probe). Measure the resistance between test pin No. 41 at the breakout box and the signal side of the OCS harness connector.

    Fig 6: OCS-OCIL Circuit
    G120781

    If resistance is less than 5 ohms, go to next step. If not, repair open circuit(s) as necessary, remove breakout box, reconnect components and rerun QUICK TEST.

  11. Checking Circuit(s) For Shorts To Power. With key off, ensure breakout box is installed and ECA is disconnected. Set DVOM on 200k-ohm scale. For 4X4 LOW Circuit, disconnect 4X4 LOW switch. Measure resistance between test pin No. 12 and test pins No. 37 and 57 at the breakout box. For OCS-OCIL Circuit, disconnect OCS switch. Measure resistance between test pin No. 41 and test pins No. 37 and 57 at the breakout box. Measure resistance between test pin No. 32 and test pins No. 37 and 57 at the breakout box. If resistance(s) are greater than 10k-ohms, remove breakout box, replace appropriate switch and rerun QUICK TEST. If resistance(s) are not greater than 10k ohms, repair short circuit(s), remove breakout box, reconnect ECA and rerun QUICK TEST.
  12. Service Code 91, 92, 93, 94, 98 And 99 Circuit Identification. These service codes indicate that the appropriate On/Off solenoid is out of Self-Test range. This may cause harsh, early or late shifting. Correct voltage is 9.00-14.50 when ON and less than 1.0 volt when OFF. Code 98 indicates Electronic Pressure Control (EPC) solenoid may have a faulty driver in the ECA. Code 99 indicates a faulty EPC circuit which may cause harsh shifting and clutch wear. Possible causes for these codes are: solenoid resistance is out of limits, harness circuit is open or grounded, faulty ECA. Verify code match with the following table.
    CODE MATCH IDENTIFICATION

    Solenoid Type ECA Signal Test Pin KOEO Self-Test Code
    SS1 - Shift Solenoid #1 52 91
    SS2 - Shift Solenoid #2 19 92
    CCS - Coast Clutch Solenoid 55 93
    CCC - Converter Clutch Solenoid 53 94
    EPC - Electronic Pressure Control 38 98/99

    If any of the listed codes are present, go to next step. If codes are not present, go to KOEO Self-Test procedures.

  13. Enter Output State Check. Turn key off and wait 10 seconds, set DVOM on 20-volt scale. A VOM or DVOM MUST be used for this test. Connect DVOM negative test lead to STO circuit at Self-Test connector and positive test lead to battery positive. Jumper STI circuit to SIGNAL RETURN at the Self-Test connector. Perform KOEO Self-Test until all Continuous Codes have been displayed. DVOM will indicate less than 1.0 volt when test is complete. Depress and release throttle. If voltage increases, remain in Output State Check and go to next step. If voltage does not increase, depress throttle to WOT and release. If STO voltage does not increase, go to TEST D16 - OUTPUT STATE, step 1), leave test equipment hooked up.
  14. Check Suspect E4OD Solenoid Electrical Operation. With KOEO, disconnect transmission solenoid bulkhead connector. Use a mirror to inspect both ends of connector for damage or corrosion. Service or repair as necessary. Connect DVOM positive test lead to VPWR circuit and negative test lead to ECA signal test pin at the bulkhead connector (see step 12). Set DVOM on 20-volt scale. While observing DVOM, depress and release the throttle several times to cycle output on and off. If suspected solenoid output circuit voltage change is greater than 1.0 volt, service or repair solenoid. If voltage change is not greater than 1.0 volt, remove jumper and go to next step.
  15. Checking E4OD Transmission Solenoid Resistance. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector and inspect for corroded or damaged pins. Service or repair as necessary. Install breakout box, leave ECA disconnected. Connect transmission bulkhead connector. Set DVOM on 200-ohm scale. Measure resistance between test pins No. 37 and 57 and ECA signal test pin at the breakout box. If resistance is within specification, go to step 17). If not, go to next step.
    SOLENOID RESISTANCE

    Ambient Temperature °F Solenoid Type Resistance - Ohms
    -40-32 SS, CCC, CCS 16.0-20.5
    -40-32 EPC 3.25-4.25
    32-230 SS, CCC, CCS 20.5-30.0
    32-230 EPC 4.25-6.50
  16. Checking Continuity Of E4OD Solenoid Harness. Turn key off and wait 10 seconds. Install breakout box, leaving ECA disconnected. Disconnect transmission bulkhead connector. Set DVOM on 200-ohm scale. Measure resistance between the ECA signal test pin at the breakout box and transmission bulkhead connector. Measure resistance between test pins No. 37 and 57 at the breakout box and EPCPWR and VPWR pins at the E4OD transmission bulkhead connector (refer to circuit diagram at start of test). If all resistances are less than 5 ohms, go to next step. If not, remove breakout box, repair open circuit and reconnect ECA and solenoids. Rerun QUICK TEST.
  17. Checking E4OD Solenoid Harness For Short To Ground. Turn key off and wait 10 seconds. Install breakout box, leaving ECA disconnected. Ensure transmission bulkhead connector is disconnected. Set DVOM on 200k-ohm scale. Measure resistance between ECA signal test pin (see table at step 12) and test pins No. 40, 46 and 60 at the breakout box. Measure resistance between the ECA signal test pin at the breakout box and chassis ground. If all resistances are greater than 10k-ohms, go to next step. If not, repair short circuit(s), remove breakout box, reconnect ECA and solenoid(s). Rerun QUICK TEST.
  18. Checking E4OD Solenoid Harness For Short To Power. Turn key off and wait 10 seconds. Install breakout box, leaving ECA disconnected. Ensure transmission bulkhead connector is disconnected. Set DVOM on 200k-ohm scale. Measure resistance between ECA signal test pin (see table in step 12) ) and test pins No. 37 and 57 at breakout box. If all resistances are greater than 10k-ohms, go to next step. If not, repair short circuit(s), remove breakout box, reconnect ECA and solenoid(s). Rerun QUICK TEST.
  19. Checking Voltage Of VPWR To E4OD Solenoids. Turn key off and wait 10 seconds. Install breakout box, ensure ECA is connected. Ensure transmission bulkhead connector is disconnected. Set DVOM on 20-volt scale. With KOEO, measure voltage between test pins No. 37 and 57 at the bulkhead connector and chassis or battery ground. If voltage is greater than 10.5 volts, go to next step. If not, replace ECA, reconnect components and rerun QUICK TEST.
  20. Check Solenoid Driver Signal. With key off, install breakout box and leave ECA connected. Disconnect transmission bulkhead connector. Connect a test light between test pin No. 37 or 57 and the ECA signal test pin at the breakout box. With KOEO, wait 10 seconds. Initiate KOEO Self-Test. If test light flashes momentarily and then stays off, repair transmission solenoids as necessary, driver signal is okay. If test light does not flash, replace ECA, reconnect solenoid(s) and rerun QUICK TEST. If test light is always on, solenoid driver is shorted to ground in ECA. Replace ECA, reconnect solenoid(s) and rerun QUICK TEST.
  21. Code 26: Check Transmission Oil Operating Temperature. Code 26 indicates Transmission Oil Temperature (TOT) sensor is out of Self-Test range. Correct voltage is 0.21-3.50. Possible causes for this fault are: TOT resistance is out of range or ECA is faulty. Drive vehicle normally in city traffic for 20-30 minutes to bring transmission oil temperature to at least 50° F (10°C). In extremely cold weather a longer warm-up drive may be necessary. Rerun QUICK TEST. If code 26 is still present, go to next step. If not, service or repair other codes as necessary.
  22. Checking For VREF At Throttle Position Sensor (TPS). Refer to Figure . Turn key off and wait 10 seconds. Disconnect ECA 60 pin connector and inspect for corroded or damaged pins. Service or repair as necessary. Install breakout box and connect ECA to breakout box. Disconnect TPS and set DVOM on 20-volt scale. With KOEO, measure voltage between VREF and SIGNAL RETURN at the TPS vehicle harness connector. If voltage is 4.0-6.0 volts, reconnect TPS and go to next step. If not, go to TEST A3 - REF  . VOLTAGE, step 1).
  23. Checking Resistance Of TOT Sensor. Ensure transmission temperature is 50°F (10°C), if transmission has cooled down, repeat test drive. Turn key off and wait 10 seconds. Ensure breakout box is installed and ECA is disconnected. Ensure bulkhead connector is connected at transmission. Set DVOM on 200k-ohm scale. With KOEO, ensure transmission oil pan is "warm to touch" on side away from exhaust manifold. Measure resistance between test pin No. 42 and test pin No. 46 at the breakout box. Refer to the TRANSMISSION OIL TEMPERATURE (TOT) SENSOR RESISTANCE  table. If TOT resistance is within specification, go to next step. If not, repair or replace TOT sensor.
    TRANSMISSION OIL TEMPERATURE (TOT) SENSOR RESISTANCE

    Trans. Oil Temp. - °F Resistance - Ohms
    32-58 37,000-100,000
    59-104 16,000-37,000
    105-158 5000-16,000
    159-194 2700-5000
    195-230 1500-2700
    231-266 800-1500
  24. Checking TOT Sensor Resistance In Relation To Oil Temperature Change. TOT sensor may be within specification range (0.8k-100k ohms) and not correspond to temperature. Ensure transmission fluid is at operating temperature. Measure TOT resistance again and compare to resistance recorded in step 23). If resistance increased or decreased due to temperature change, replace ECA. If not, replace breakout box, reconnect ECA, and replace temperature sensor.
  25. Code 56: Attempt To Generate Code 66. Code 56 indicates TOT signal is greater than Self-Test maximum value of 4.80 volts. Possible causes for this fault are: faulty TOT sensor, open harness circuit, faulty ECA. Turn key off and wait 10 seconds. Disconnect transmission bulkhead connector from TOT sensor. Inspect for corroded or damaged pins. Service or repair as necessary. Insert a jumper wire at the bulkhead connector between TOT SIGNAL and SIGNAL RETURN. Run KOEO Self-Test. If Code 66 is present, remove jumper wire and service or replace TOT sensor. If not, remove jumper wire and go to next step.
  26. Check Continuity Of TOT SIGNAL And SIGNAL RETURN Circuit. Turn key off and wait 10 seconds. Ensure bulkhead connector is disconnected at transmission. Disconnect ECA 60-pin connector and inspect for corroded or damaged pins. Service or repair as necessary. Install breakout box, leave ECA disconnected. Set DVOM on 200-ohm scale. Measure resistance between TOT SIGNAL at the bulkhead connector and test pin No. 42 at the breakout box. Measure the resistance between SIGNAL RETURN at the bulkhead connector and test pin 46 at the breakout box. If both resistances are less than 5 ohms, replace ECA, remove breakout box, reconnect ECA and bulkhead connector. Rerun QUICK TEST. If resistances are not less than 5 ohms, repair open circuits, remove breakout box and reconnect ECA. Rerun QUICK TEST.
  27. Code 66: Attempt To Generate Code 56. Code 66 indicates that TOT signal is less than 0.15 volt (Self-Test minimum value). Possible causes for this fault are: faulty TOT sensor, grounded harness or faulty ECA. Turn key off and wait 10 seconds, disconnect transmission connector from bulkhead connector. Inspect for corroded or damaged pins. Service or repair as necessary. Run KOEO Self-Test. If Code 56 is present, service or replace TOT sensor. If not, go to next step.
  28. Checking VREF At TPS. Refer to wiring circuit diagrams in CIRCUIT TESTS B8 and B17. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector and inspect for corroded or damaged pins. Service or repair as necessary. Install breakout box and connect ECA to breakout box. Disconnect TPS and set DVOM on 20-volt scale. With KOEO, measure voltage between VREF and SIGNAL RETURN at the TPS vehicle harness connector. If voltage is 4.0-6.0 volts, reconnect TPS and go to next step. If not, go to TEST A3 - REF  . VOLTAGE, step 1).
  29. Checking TOT Signal For Short To Ground. Turn key off and wait 10 seconds. Ensure bulkhead is disconnected at transmission. With breakout box installed and ECA disconnected, set DVOM on 200k-ohm scale. Measure resistance between test pin No. 42 and test pins No. 40, 46 and 60 at the breakout box. If all resistances are greater than 10k-ohms, replace ECA and remove breakout box. Reconnect components and rerun QUICK TEST. If resistances are not greater than 10k-ohms, repair short circuit, remove breakout box and reconnect components. Rerun QUICK TEST.
  30. Checking MLP, TOT Sensor And E4OD Solenoid Drive Cycle. Bring engine to operating temperature. Verify transmission fluid level and that all components are connected. Run KOEO Self-Test and record Continuous Memory Codes. If Codes 49, 59 or 69 are present, go to step 36). If Codes are not present, record and clear Continuous Memory Codes. Select "D" range and enable "OD". Drive vehicle in city traffic using moderate acceleration. Hold throttle opening steady while transmission is shifting through all four gears and hold throttle steady for an additional 15 seconds. Apply brakes on coming to a stop and remained stopped for 20 seconds. Repeat previous drive step. Rerun KOEO Self-Test and record Continuous Memory Codes. If a Code 11 is present, go to next step. If Code 29 is present, go to TEST B12 - VSS  . For Codes 56, 62, 66, 67 or 99, go to step 32).
  31. Attempt To Generate Continuous Memory Code 56, 62, 66, 67 and 99. Before performing any procedures in this step, complete the drive cycle test. Drive vehicle approximately 15 minutes over a rough road to simulate road shock. Observe MIL LED while driving for indication of a fault. If MIL flashes ON and OFF, go to next step. If light does not flash, fault may not be duplicated at this time. Testing is complete.
  32. Check Circuit Using KOEO Continuous Monitor Mode. Enter KOEO Continuous Monitor Mode. Observe VOM or STAR LED for indication of a fault while performing the following. For MLP Sensor (Code 67), lightly tap on MLP sensor to simulate road shock. Wiggle connector at MLP sensor. For Transmission Solenoids (Codes 62 or 99) And TOT Sensor (Codes 56 or 66), wiggle transmission bulkhead connector. If a fault is indicated, isolate fault and service or repair as necessary. Clear Continuous Memory Codes and rerun QUICK TEST. If a fault is not indicated, go to step 35).
  33. Checking EEC-IV Harness. Ensure vehicle is still in KOEO Continuous Monitor Mode. Observe VOM for an indication of a fault while performing the following: using illustration in step 34), grasp harness close to sensor or transmission connector and perform "Wiggle" test while working from transmission to dash panel and ECA. If a fault is indicated, isolate fault and service as necessary. Clear Continuous Memory Codes and rerun QUICK TEST. If no fault is indicated, go to step 35).
  34. See Fig 7 , Circuit Diagram For Continuous Monitor Mode.
    Fig 7: E4OD Vehicle Harness Circuit
    G120782
  35. Checking ECA And Harness Connectors. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Disconnect ECA 60 pin connector and inspect for corroded or damaged pins. Service or repair as necessary. If connectors and terminals are okay, fault may not be duplicated at this time. Clear Continuous Memory Codes. If connectors or terminals are faulty, service or repair as necessary. Clear codes and rerun QUICK TEST.
  36. Isolating Faults For Continuous Memory Codes 49, 59, and 69. Codes 49, 59 and 69 indicate that the transmission went through 4 consecutive incorrect shifts in an upward or downward shift sequence. When changing a gear the SS1 or SS2 solenoid remained ON or OFF an extended amount of time. Possible causes for these faults are: intermittent harness continuity, stuck shift solenoid. Rerun KOEO Self-Test. If any other codes appear during the KOEO Self-Test in addition to Codes 49, 59 or 69, service other codes first. If not, go to next step.
  37. Checking Circuits Using KOEO Continuous Monitor Mode. Enter KOEO Continuous Monitor Mode. Observe VOM or STAR LED for indication of a fault while performing the following: wiggle, shake or bend a small section of system harness while working from dash panel and ECA to transmission bulkhead connector. If a fault is indicated, disconnect connectors and inspect connectors and harness for damage. Clear codes and rerun QUICK TEST. If a fault is not indicated, service or replace SS1 and SS2 solenoids as necessary.
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