P2769
P2769-TRANSMISSION TCC CONTROL CIRCUIT LOW
For the Transmission circuit diagram Refer to Transmission Control Systems/Diagram.
For a complete wiring diagram refer to diagrams.
Theory of Operation
The Torque Converter Clutch (TCC) solenoid is used to engage the TCC which improves fuel economy.
- When Monitored:
Continuously with the ignition on.
- Set Condition:
This DTC will set if the voltage detected by the ECM for the Torque Converter Clutch Solenoid Control circuit is different than the expected voltage. Note: To clear this DTC it is necessary to drive the vehicle at a sustained speed which would allow the TCC and/or Overdrive Clutch to operate.
Possible Causes
- TRANSMISSION CONTROL RELAY DTCS PRESENT
- (F941) FUSED IGNITION SWITCH OUTPUT CIRCUIT (RUN-START) OPEN
- (T16) TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT OPEN
- (T16) TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT SHORT TO GROUND
- (T75) TCC SOLENOID CONTROL CIRCUIT SHORT TO GROUND
- (T75) TCC SOLENOID CONTROL CIRCUIT SHORT TO OTHER CIRCUITS
- TRANSMISSION CONTROL RELAY - POOR CONTACTS
- TORQUE CONVERTER CLUTCH SOLENOID
- ENGINE CONTROL MODULE
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
Diagnostic Test
1. CHECK IF THERE ANY TRANSMISSION CONTROL RELAY DTCS PRESENT
Ignition on, engine not running.
With the scan tool, read Engine DTCs.
Are there any Transmission Control Relay DTCs also present?
Yes >>Refer to the Transmission category and perform the appropriate symptom(s).
No >>Go To 2
2. CHECK IF THE DTC IS CURRENT
With the scan tool, read Engine DTCs.
Record the Freeze Frame data for the reported DTC.
With the scan tool, erase DTCs.
Turn the ignition off to the lock position.
Using the Freeze Frame data recorded earlier, try to duplicate the conditions in which the DTC originally set.
NOTE: It may be necessary to road test the vehicle to duplicate the original set conditions. With the scan tool, read Engine DTCs.
Did the DTC reset?
Yes >>Go To 3
No >>Go To 11
3. CHECK THE (T16) TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT
Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid Assembly harness connector.
NOTE: Check connectors - Clean/repair as necessary.
Ignition on, engine not running. With the scan tool, actuate the Transmission Control Relay.
Using a 12-volt test light connected to ground, check the (T16) Transmission Control Relay Output circuit in the Transmission Solenoid Assembly harness connector.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light cycle on and off and illuminate brightly?
Yes >>Go To 4
No >>Go To 8
4. CHECK THE (T75) TORQUE CONVERTER CLUTCH SOLENOID CIRCUIT
Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid Assembly harness connector.
Ignition on, engine not running.
With the scan tool, actuate the TCC Solenoid.
Using a 12-volt test light connected to 12-volts, check the (T75) TCC Solenoid Control circuit in the Transmission Solenoid Assembly harness connector.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light cycle on and off and illuminate brightly?
Yes >>Check all internal wiring pertaining to the (T75) TCC Solenoid for an open, short, and bent or broken terminals. If solenoid for an open 1, short and bent or broken terminals internal wiring problems are found, replace the Transmission Solenoid Assembly per the Service Information.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
No >>Go To 5
5. (T75) TCC SOLENOID CONTROL CIRCUIT SHORT TO GROUND
Turn the ignition off to the lock position.
Disconnect the ECM harness connectors.
Measure the resistance between ground and the (T75) TCC Solenoid Control circuit.
Is the resistance below 5.0 ohms?
Yes >>Repair the (T75) TCC Solenoid Control circuit for a short to ground.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
No >>Go To 6
6. (T75) TCC SOLENOID CONTROL CIRCUIT OPEN
Measure the resistance of the (T75) TCC Solenoid Control circuit between the ECM C2 harness connector and the Transmission Solenoid Assembly harness connector.
Is the resistance below 5.0 ohms?
Yes >>Repair the (T75) TCC Solenoid Control circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER 1 (DIESEL). Verification Tests
No >>Go To 7
7. (T75) TCC SOLENOID CONTROL CIRCUIT SHORT TO OTHER CIRCUITS
Measure the resistance between the (T75) TCC Solenoid Control circuit and all other circuits in the Transmission Solenoid Assembly harness connector.
Is the resistance below 5.0 ohms between the (T75) TCC Solenoid Control circuit and any other circuit in the Transmission Solenoid Assembly harness connector?
Yes >>Repair the (T75) TCC Solenoid Control circuit for a short to another circuit(s).
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
No >>Using the schematics as a guide, check the Engine Control Module (ECM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the ECM per the Service Information.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
8. (941) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT OPEN
Turn the ignition off to the lock position. Remove the Transmission Control Relay. Ignition on, engine not running.
Using a 12-volt test light connected to ground, check the (F941) Fused Ignition Switch Output (Run-Start) circuit in the Transmission Control Relay connector.
Does the test light illuminate brightly?
Yes >>Go To 9
No >>Repair the (F941) Fused Ignition Switch Output (Run-Start) circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
9. (T16) TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT OPEN
Connect a jumper wire between the Fused B(+) circuit and the Transmission Control Relay Output circuit in the Transmission Control Relay connector.
Using a 12-volt test light connected to ground, check the Fused Transmission Relay Control Output circuit in the Transmission Solenoid Assembly harness connector.
Does the test light illuminate brightly?
Yes >>Go To 10
No >>Repair the (T16) Transmission Control Relay Output circuit for an open. If the fuse is open make sure to check for a short to ground.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
10. (T16) TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT SHORT TO GROUND
Turn the ignition off to the lock position.
Measure the resistance between ground and the (T16) Transmission Control Relay Output circuit in the Transmission Control Relay connector.
Is the resistance above 100k ohms?
Yes >>Replace the Transmission Control Relay.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
No >>Repair the (T16) Transmission Control Relay Output circuit for a short to ground.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
11. INTERMITTENT WIRING AND CONNECTORS
The conditions necessary set this DTC are not present at this time.
Use the Freeze Frame Data to help duplicate the conditions that set the DTC. Pay particular attention to the DTC set conditions, such as, VSS, MAP, ECT, and Load.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
Refer to any technical service bulletins that may apply.
Were there any problems found?
Yes >>Repair as necessary.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). Verification Tests
No >>Test Complete.