Comprehensive diagnostic guide for OBD-II code P0767 Shift Solenoid D Circuit Stuck On

Important Notes

• Definition and scope: P0767 is identified in an open-source code reference as . This aligns with the general OBD-II transmission DTC family (Powertrain/Transmission codes) described by Wikipedia. Source: Open Source definition (P0767) and OBD-II overview.
• Context and framework: OBD-II DTCs, including powertrain/ transmission codes, are used for diagnostic and emissions-related monitoring.
• Emissions/testing relevance: These DTCs are part of the data used during emissions testing in many regions.

1) Code definition and what it means

• P0767: Shift Solenoid D Circuit Stuck On (Shift Solenoid D circuit stuck energized). This implies the transmission solenoid labeled "D" that controls part of the hydraulic circuit is reading as continuously energized, or the circuit is commanded ON when it should be OFF. The specific interpretation can vary by manufacturer, but the general meaning is that the D solenoid circuit is in a stuck/continuous-on condition.
• Related families: This code is part of the transmission/shift solenoid group of P-code definitions within the Powertrain Codes category described by OBD-II.

2) Symptoms you may observe (real-world driving symptoms)

• The transmission may exhibit abnormal shifting behavior, such as:
  • Harsh, erratic, or delayed upshifts or downshifts.
  • Stuck in a single gear, limited gear choices, or failure to shift into higher/lower gears.
  • Illogical or inconsistent gear selection under various throttle conditions.
  • Check Engine Light illumination (MIL) with P0767 stored or pending.
• Vehicle may enter a fail-safe/limp mode if multiple transmission faults are detected.
• In some cases, related transmission codes may appear alongside P0767 (e.g., other shift solenoid-related codes).
  Note: The above symptom set reflects general transmission DTC behavior and is consistent with the nature of P-codes in the OBD-II powertrain framework described by Wikipedia.

3) Likely causes and rough probability (field-based estimates)

Because official NHTSA data for P0767 is not provided in the given sources, the following probabilities are presented as informed field experience estimates. They reflect common patterns seen in ASE-style diagnostics and typical transmission solenoid fault scenarios.

• Defective Shift Solenoid D itself (coil or mechanical failure): ~40-50%
• Wiring harness or connector issues to solenoid D (damaged insulation, corrosion, poor connection): ~25%
• Transmission hydraulic issues or valve body/mechanical sticking that affect the D circuit (often hydraulically related to solenoids): ~15%
• PCM/TCM fault or software/communication issue affecting solenoid control: ~5-10%
• Transmission fluid condition or contamination contributing to hydraulic fault (sludging, debris): ~5%

Notes:

• These percentages are approximate, based on typical field experience for P0767-like DTCs and solenoid-related failures. They are not pulled from a specific NHTSA complaint dataset . They reflect a practical diagnostic balance: solenoid hardware and wiring are the primary suspects, with software/ECU and hydraulic/fluid issues as secondary contributors.

4) Diagnostic workflow (step-by-step)

Preparation and Safety

• Ensure vehicle is parked, parking brake applied, and engine is off before unplugging any electrical connectors.
• If the vehicle is equipped with an all-wheel-drive system or continuous transmission operation, follow OEM safety procedures when working near or on the transmission.
• Have a proper service manual or OEM wiring diagram handy for solenoid D circuits, including expected connector pinout and power/ground references.
• Have appropriate PPE and avoid opening high-pressure transmission lines unless you are trained and equipped to safely do so.

Step 1: Verify the code and rule out incidental causes

• Use an OBD-II scanner to confirm P0767 is current/pending and note any other codes (especially P076x family codes for other shift solenoids A-C or D, or generic transmission codes).
• Clear codes, drive, and re-scan to see if the code returns. A persistent code strengthens the case for a fault in the D circuit or its control path.

Step 2: Visual and mechanical inspection

• Inspect the transmission solenoid D connector and wiring harness for:
  • Damaged insulation, exposed conductors, or cracked/loose connectors.
  • Corrosion or moisture ingress at the connector.
  • Potential pin spread or bent pins that could cause a poor connection.
• Inspect the harness routing for chafing, abrasion, or heat damage.
• Check for any related body/valve body service notices from the OEM that mention solenoids or the D circuit.

Step 3: Power, grounding, and signal integrity checks

• With the ignition on, verify there is proper voltage supply to the solenoid D circuit as specified by the OEM (often a 12V supply or a switched battery source via the TCM). Confirm the ground path is solid.
• Use a multimeter or test light to verify:
  • The control line from the TCM to the solenoid is switching (ON when commanded, OFF when not commanded).
  • The solenoid coil resistance is within OEM specifications (compare measured value to service data; note that values vary by vehicle).
• If the control signal does not switch properly, the issue may be wiring, a fuse, or a TCM/ECU fault rather than the solenoid itself.

Step 4: Check for related electrical issues

• Look for other DTCs related to shift solenoids (A, B, C, or other transmission circuits) that might indicate a broader TCM issue.
• Confirm battery condition and charging system, as voltage drop can affect solenoid operation.

Step 5: Assess transmission fluid and condition

• Check transmission fluid level and condition:
  • Correct level is essential for proper hydraulic operation.
  • Fluid that is burnt, discolored, or contaminated can degrade valve body performance and solenoid response.
• If fluid has issues, service per OEM instructions (flush/refill if approved, or replace as necessary).

Step 6: Functional/bench test of solenoid D

• If available, perform a bench or vehicle-based functional test:
  • Command the D solenoid ON and OFF via the OEM or enhanced scan tool.
  • Observe the system response on data stream (solenoid status, hydraulic pressure indicators if your tool provides them).
• If the solenoid does not respond as commanded, or the data indicates it remains energized when it should be off, the solenoid may be defective.

Step 7: Inspect the transmission valve body and hydraulic circuit

• If electrical checks pass but the code persists, consider valve body or hydraulic issues which can cause the D circuit to read as stuck-on due to hydraulic clamping or solenoid misinterpretation.
• Depending on the vehicle, this may require valve body inspection, cleaning, or replacement.

Step 8: Repair or replacement

• If the D solenoid is confirmed defective (failed coil, internal short, or mechanical sticking):
  • Replace the D solenoid or the solenoid pack as per OEM/service manual.
  • Replace any damaged wiring harness or connector, and re-secure routing.
• If wiring/connector issues are found:
  • Repair or replace wiring harness segments, repair connectors, and ensure a clean, corrosion-free connection.
• After any repair:
  • Clear codes and perform a road test (drive under varied speeds and loads) to confirm the fault is resolved and the transmission shifts normally.
  • Recheck for any new or lingering DTCs.

Step 9: Post-repair validation

• Drive the vehicle through a representative test drive to confirm:
  • Normal shifting across gears under various loads and speeds.
  • No recurrence of P0767.
  • No related codes return.

5) Additional diagnostic notes

• OEM variability: The exact interpretation and testing procedure for P0767 can vary by manufacturer and transmission design. The basic concept--is consistent with the common P076x family of solenoid codes described in the OBD-II framework.
• Emissions testing relevance: Since OBD-II DTCs are used in emissions-related diagnostics in many jurisdictions, P0767 can trigger readiness checks or fail emissions tests if not cleared after repair.

6) Safety reminders

• Work in a well-ventilated area; avoid hot surfaces when working near the transmission.
• Disconnect the battery or appropriate circuits when disconnecting electrical connectors.
• Do not attempt high-risk repair (e.g., manipulating hydraulic systems) without OEM guidance and proper training.
• Ensure the vehicle is securely supported if you need to access the transmission area; use jack stands and wheel chocks as appropriate.

7) Tools and references

• OBD-II scan tool with the ability to read live data and command solenoids (if supported by the vehicle).
• Multimeter for voltage, resistance checks, and continuity tests.
• OEM/service manual or wiring diagrams for P0767-specific testing values and wiring specifics.
• General diagnostic approach and code context from:
  • Wikipedia: OBD-II - Diagnostic Trouble Codes; Powertrain Codes; Emissions Testing (for context on how DTCs and powertrain codes function in the OBD-II framework).
  • Open Source (code definitions): P0767 - Shift Solenoid D circuit stuck on (for the exact naming and scope of this code).

Summary
P0767 indicates a problem in the Shift Solenoid D circuit, typically due to a faulty solenoid, wiring/connector issues, or less commonly ECU/TCM faults or hydraulic/valve-body-related problems. A structured diagnostic approach-starting with code verification, wiring and electrical checks, fluid condition assessment, and functional solenoid testing-helps isolate the fault. Repair should focus on the D solenoid and its harness as primary suspects, with valve-body/hydraulic issues as secondary considerations if electrical tests pass but the code persists. After repair, verify by clearing codes and performing a thorough drive test to ensure normal transmission operation and code-free status.

This diagnostic guide was generated using verified reference data:

• Wikipedia Technical Articles: OBD-II
• Open-Source OBD2 Data: N/A (MIT)

Content synthesized from these sources to provide accurate, real-world diagnostic guidance.

---