P2770

Converter Clutch Circuit High

P2770 is a generic OBD-II powertrain diagnostic trouble code: Converter Clutch Circuit High. It is logged by the engine control unit when the powertrain monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code
P2770
Group
Powertrain
System
Powertrain
Severity
Warning (MIL on, possible limp mode)
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What P2770 means

P2770 is the complement to P2769 and is set when the TCM detects an abnormally high voltage on the torque converter clutch solenoid control circuit. A high-circuit condition typically indicates an open circuit in the solenoid winding, a broken wire between the TCM and the solenoid, or a short to voltage on the control line.

With the control circuit open or shorted high, the TCM cannot deliver the commanded current to engage the TCC. The module recognises that the measured signal does not correspond to its output command and stores P2770. Like the low-circuit variant, the TCM usually disables TCC operation as a protective measure, which affects fuel economy and thermal management of the torque converter.

Diagnostic procedure follows the same general sequence as other circuit-high faults: scan all codes, inspect the harness, verify solenoid resistance, then check for open or short-to-voltage conditions before evaluating the TCM. Intermittent faults are often caused by broken wires inside intact insulation and may require a wiggle test of the harness under live conditions.

Common causes

Most-frequently reported root causes when P2770 is logged.

  • 1
    Open circuit in the TCC solenoid winding.
  • 2
    Broken or corroded wire in the harness between the TCM and the solenoid.
  • 3
    Short to battery voltage on the TCC solenoid control wire.
  • 4
    Damaged or spread connector pin causing loss of continuity.
  • 5
    Faulty TCM with a failed pull-down driver.
  • 6
    Internal solenoid mechanical seizure leading to winding burnout.
  • 7
    Improper repair or splice in the transmission harness.

Symptoms drivers notice

MIL illuminated.
Torque converter clutch fails to engage at cruise speeds.
Fuel economy noticeably reduced on highway driving.
Transmission running hotter than normal.
Possible harsh or delayed gear shifts if the TCM enters a fallback strategy.

How to diagnose P2770

A typical diagnostic flow when this code is present.

  1. 1
    Connect a scan tool and document all active and pending DTCs with freeze frame data.
  2. 2
    Inspect the transmission external connector and harness for open circuits, broken wires, or corrosion.
  3. 3
    Measure TCC solenoid coil resistance at the transmission connector and verify against specification.
  4. 4
    With the TCM disconnected, check for short to battery voltage on the TCC control circuit.
  5. 5
    Perform a wiggle test on the harness while monitoring resistance to identify intermittent open circuits.
  6. 6
    Verify TCM power supply and ground quality before attributing the fault to the TCM.
  7. 7
    Repair any wiring faults found; replace the solenoid if resistance is outside specification.

Related powertrain codes

Frequently asked questions

What is the difference between P2769 and P2770?

P2769 signals a low-circuit condition (short to ground or shorted coil), while P2770 signals a high-circuit condition (open circuit or short to voltage).

Can both P2769 and P2770 be set at the same time?

Unlikely under normal fault conditions; if both are present simultaneously, suspect a faulty TCM or a measurement circuit issue.

Will the torque converter be damaged by this fault?

The converter itself is not immediately damaged, but prolonged high-slip operation increases heat and wear on the converter clutch surfaces.

Does P2770 require transmission removal for repair?

Not necessarily. Most TCC solenoids are accessible via the oil pan and valve body without removing the entire transmission.

Disabling P2770 in software

RaceTune can permanently disable P2770 — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.

Permanent
The monitor is disabled in the ECU itself — not just cleared. It cannot return.
Tailored to your file
Each patch is matched to your specific software version — never a one-size-fits-all file.
Reversible
The original file is always preserved. Reflash the stock to return the ECU to factory state.

ECUs with a P2770 disable in our catalogue

Confirmed coverage from our recipe database — we support many more families. Upload your file and our identifier will match it automatically.

  • Bosch MD1CS001 verified 1 software version

Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.

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