Pinpoint Test A: Shift and TCC Solenoids
Pinpoint Tests - OSC Equipped Vehicle
Any time an electrical connector or solenoid body is disconnected, inspect the connector for pin condition, corrosion and contamination. Also inspect the connector seal for damage. Clean, repair or install a new component as required.
Shift Solenoids Pre-Diagnosis
Use the following shift solenoid operation information when carrying out Pinpoint Test A.
Solenoid Operation Chart
a When a manual pull-in occurs above a calibrated speed, the transmission will not downshift from the higher gear until the vehicle speed drops below this calibrated speed.
EC = Electronically Controlled
HD = Hydraulically Disabled
Shift Solenoid Failure Mode Chart "Always Off"
Failed off due to PCM and/or vehicle wiring concerns, shift solenoid electrically or hydraulically stuck off.
*No engine braking.
Shift Solenoid Failure Mode Chart "Always On"
Failed on due to PCM and/or vehicle wiring concerns, shift solenoid electrically or hydraulically stuck on.
*No engine braking.
*No engine braking.
Pinpoint Tests
Refer to Wiring Diagram Set 29, Transmission Controls - 4R75E for schematic and connector information. Diagrams By Number
NOTE: Refer to all TSBs and On-Line Automotive Service Information System (OASIS) messages that pertain to the transmission concern and follow the procedure as described.
PINPOINT TEST A: SHIFT AND TCC SOLENOIDS
NOTE: Refer to the Transmission Vehicle Harness Connector illustration within the Transmission Connector Layouts Transmission Connector Layouts procedure.
NOTE: Refer to the Transmission Internal Harness Connector illustration within the Transmission Connector Layouts Transmission Connector Layouts procedure.
NOTE: Read and record all DTCs.
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A1 ELECTRONIC DIAGNOSTICS
- Vehicle in PARK.
- Ignition OFF.
- Check to make sure the transmission vehicle harness C1472 is fully seated, the terminals are fully engaged in connector and are in good condition before proceeding.
- Connect the scan tool.
- Ignition ON.
- Access the transmission PIDs.
- Is the scan tool able to access the transmission PIDs?
Yes
GO to A2.
No
REPEAT procedure to access the transmission PIDs. If the scan tool did not access the transmission PIDs, REFER to Computers and Control Systems for diagnosis of PCM.
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A2 WIGGLE TEST
- Select PIDs to be monitored.
- Select ON to turn suspect solenoid on.
- Wiggle all wiring and connectors to the transmission. Monitor the solenoid state for changes.
- Select OFF to turn solenoid off.
- Does the suspect solenoid(s) fault state change?
Yes
REPAIR open or short in the vehicle harness or connector.
No
GO to A3.
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A3 SOLENOID FUNCTIONAL CHECK
- Monitor each solenoid state.
- Turn each solenoid ON and OFF.
- Does the solenoid turn ON and OFF when commanded and can solenoid activation be heard?
Yes
GO to A4.
No
GO to A5.
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A4 VERIFY SHIFT OR TCC SOLENOID OPERATION
- Using the scan tool, select the SSA, SSB and/or TCC solenoid PIDs.
- While driving the vehicle, maintain speed at 48 km/h (30 mph).
- Command the selected solenoid ON and OFF.
- Repeat steps for remaining solenoids as needed.
- Does the transmission upshift/downshift or Torque Converter Clutch (TCC) engage/disengage when commanded?
Yes
CLEAR the DTCs. ROAD TEST to verify if concern is still present. If concern is still present, REFER to Diagnosis By Symptom Diagnosis By Symptom to diagnose shift or torque converter concern.
No
GO to A5.
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A5 CHECK FOR BATTERY VOLTAGE
- Ignition OFF.
- Disconnect: Transmission Vehicle Harness C1472.
- Inspect the connector for damaged pins.
- Ignition ON.
- Measure the voltage between the transmission vehicle harness C1472-1, circuit CBB79 (VT/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to A6.
No
REPAIR transmission vehicle harness circuit CBB79 (VT/WH). TEST the system for normal operation.
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A6 CHECK VEHICLE HARNESS SIGNAL CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: PCM C175T.
- Measure the resistance between the transmission vehicle harness C1472, harness side and PCM C175T, harness side using the following chart.
- Is the resistance less than 5 ohms?
Yes
GO to A7.
No
REPAIR the transmission vehicle harness circuit for an open. CLEAR the DTCs. TEST the system for normal operation.
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A7 CHECK VEHICLE HARNESS SIGNAL CIRCUITS FOR SHORT TO GROUND
- Measure the resistance between transmission vehicle harness C1472, harness side and ground using the following chart.
- Is the resistance greater than 10,000 ohms?
Yes
GO to A8.
No
REPAIR the transmission vehicle harness circuit for a short to ground. CLEAR the DTCs. TEST the system for normal operation.
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A8 CHECK THE TRANSMISSION INTERNAL HARNESS/COMPONENT FOR AN OPEN
- For Shift Solenoid A (SSA), measure the resistance between C1472-1 and C1472-6.
- For Shift Solenoid B (SSB), measure the resistance between C1472-1 and C1472-5.
- For TCC, measure the resistance between C1472-1 and C1472-2.
- Is the resistance within the specification?
Yes
GO to A9.
No
INSPECT the transmission internal harness for an open. If no open is found, REPLACE the faulty component. CLEAR the DTCs. TEST the system for normal operation.
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A9 CHECK THE INTERNAL HARNESS FOR A SHORT TO GROUND
- Measure the resistance between the transmission internal harness C1472, harness side and ground using the following chart.
- Is the resistance greater than 10,000 ohms?
Yes
REPLACE the PCM. REFER to Electronic Engine Controls Service and Repair. TEST the system for normal operation.
No
REPLACE the transmission internal harness. CLEAR the DTCs. TEST the system for normal operation.
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