1What Does P2765 Mean?
P2765 indicates the Transmission Control Module (TCM) has detected a high voltage condition in the Torque Converter Clutch (TCC) solenoid control circuit. The TCM monitors solenoid current to engage/disengage the TCC lockup clutch during highway cruising. When the circuit voltage exceeds the expected operating range — typically above 12.5 V on a commanded-low signal — the TCM sets P2765 and may disable TCC operation entirely.
A stuck-off TCC causes the torque converter to slip continuously, raising transmission fluid temperature, increasing RPM at cruise speed, and reducing fuel economy by 2–5 mpg on highway driving.
2Most Affected Vehicles
6.0L / 6.2L V8 with 6-speed auto
Heavy towing configurations VERY HIGH INCIDENCE
5.0L Coyote V8 / 3.5L EcoBoost
6-speed SelectShift variants HIGH INCIDENCE
6.7L Cummins Diesel
Heavy-duty towing duty cycle MODERATE–HIGH
3Root Causes
-
Open or Shorted TCC Solenoid WindingSolenoid resistance out of spec causes circuit voltage to read high. Measure resistance across solenoid terminals — out-of-range reading confirms failure.
-
Damaged Wiring Harness or ConnectorFrayed insulation or a corroded connector pin forces circuit voltage above threshold. Common on trucks with underbody salt/corrosion exposure.
-
Failed TCM Output DriverInternal TCM driver failure prevents proper current regulation. All external components test good but fault persists after harness repair.
-
Contaminated Transmission FluidDebris in fluid blocks solenoid hydraulic passages, causing solenoid electrical feedback anomalies. Co-presents with shift quality complaints.
4Technical Specifications
Before condemning the TCM, perform a solenoid resistance test at the TCM connector (not the transmission connector). A higher reading at the TCM end vs. the transmission end isolates the fault to the harness between the two connectors — a $30 harness repair vs. a $600+ TCM replacement. This step is skipped by over 40% of technicians who misdiagnose P2765 as a TCM failure.
5Diagnostic Steps
-
1Scan All Modules with iCarsoft CR Ultra PPull all TCM and ECM codes. Note if P0741, P0740, or transmission temperature faults co-exist. Capture freeze-frame duty cycle data for the TCC solenoid.
-
2Check Transmission FluidVerify level and condition. Dark, burnt-smelling fluid indicates thermal damage. Service fluid if overdue before electrical diagnosis.
-
3Measure Solenoid ResistanceDisconnect the transmission harness connector. Measure TCC solenoid resistance. Values outside 11–13 Ω confirm solenoid failure — replace solenoid or valve body assembly.
-
4Inspect Harness & ConnectorCheck for damaged insulation, pushed-back pins, and corrosion at both the transmission and TCM connectors. Perform voltage drop test on the solenoid control wire.
-
5Live Data Monitor with iCarsoft CR Ultra PMonitor TCC solenoid duty cycle live. At 55+ mph steady cruise, duty cycle should reach 95–100%. A stuck-at-0% reading with no circuit fault confirms TCM driver failure.
-
6Clear & VerifyAfter repair, clear codes with iCarsoft CR Ultra P. Perform a 15-minute highway verification drive. Confirm TCC locks at cruise and P2765 does not recur.
- TCM live data: solenoid duty cycle, TCC slip speed, fluid temp
- Bi-directional solenoid activation test
- Full system scan: ECM, TCM, ABS, SRS
- Covers GM, Ford, Dodge, Toyota & 10,000+ models
- Free lifetime software updates
6Related Fault Codes
7Authoritative References
- P2787 — Clutch Fluid Temp Too High
- P014C — O2 Sensor Slow Response
- P0503 — VSS Intermittent
- P025A — Fuel Pump Control Module
- P040D — EGR Temp Sensor B Circuit
- P2706 — Shift Solenoid F Stuck Off
- P0051 — O2 Heater Circuit Low B1S2
- P0672 — Glow Plug Circuit Cyl 2
- P0840 — Trans Fluid Pressure Sensor A
- P0508 — Idle Air Control Circuit Low
- P0778 — Pressure Control Solenoid B
For professional technician reference only. Always verify against OEM service data for your specific vehicle VIN.
Diagnose P2765 accurately with iCarsoft CR Ultra P.
