P0796 Code: Pressure Control Solenoid C Performance or Stuck Off

What Does P0796 Pressure Control Solenoid C Mean?

P0796 is the generic OBD-II description for Pressure Control Solenoid “C” Performance or Stuck Off. Automatic transmissions and CVTs use commanded hydraulic valves to control clutch, line, or pulley pressure. The TCM changes current or duty cycle and watches pressure, speed, ratio, slip, gear, or other feedback.

Performance or stuck off is a result code, not automatically an open circuit. A valid command may produce too little, delayed, or no response. Fluid, a sticking valve, worn valve body, leak, pump, clutch, CVT belt, or biased feedback can create the mismatch. Test the circuit when an electrical companion is present.

The letter C is only a standardized circuit label. It may be a separate solenoid or part of a solenoid, valve-body, or mechatronic assembly. Identify the transmission code, parts catalog, connector view, and current chart before ordering parts.

• Audi Q7 Quick Reference Specification Book — Lists P0796 as pressure control solenoid C performance or stuck off and separates it from P0798 electrical.
• GM bulletin PIP5771B — Uses pan debris and clutch-material inspection to separate valve-body work from internal transmission repair on listed 8-speed trucks.
• Mitsubishi service-manual revision 4758 — Adds a CVT belt-inspection branch before choosing a valve-body or transaxle repair for its specified application.

P0796 Symptoms and Severity

Symptoms depend on the controlled hydraulic element, code status, and fail-safe strategy. Even a normal drive needs timely diagnosis because intermittent slip creates heat.

Repeated clearing can hide evidence while slip adds heat. Continued driving may turn a circuit or valve-body repair into internal damage.

Commanded Pressure vs Actual Transmission Response

The scan tool may show solenoid current or duty cycle, target pressure, an actual pressure sensor, commanded gear, actual ratio, input and output speeds, calculated slip, or only some of those values. No single universal PID set exists. The useful comparison is the controller command against the feedback available on that exact vehicle.

If command changes and the measured or inferred response follows, the event may be intermittent or outside the captured window. If command changes but pressure, ratio, or clutch behavior does not, look toward a sticking valve, leak, pump, filter, clutch, CVT belt, pulley, or mechanical restriction. If no command is issued, verify enable conditions, code priority, power, wiring, communication, and TCM control.

Common P0796 Causes in Diagnostic Order

There is no honest universal percentage for each cause. Fluid procedure, transmission family, companion codes, temperature, prior service, command data, pan evidence, and actual shift behavior change the order.

Tools You Need and What UR800 Can Do

How to Diagnose P0796 in 6 Steps

• 1

  Save the Complete TCM Event

  Do not erase the evidence that separates an intermittent hydraulic event from an electrical or internal failure.

  • Confirm VIN, transmission code, fluid, mileage, software, and recent service.
  • Scan every supported module; save status, suffix, freeze frame, gear, temperature, speed, ratio, slip, pressure, and solenoid data.
  • Record the triggering shift, load, temperature, warning, noise, and fail-safe behavior before any reset.
• 2

  Triage Safety and Companion Codes

  P0796 can accompany slip or pressure loss that quickly increases internal heat and damage.

  • Stop and tow for no engagement, severe slip, banging, smoke, a major leak, burnt odor, or overheating.
  • Prioritize voltage, communication, pressure, pump, ratio, speed, and other solenoid codes in OEM order.
  • Distinguish P0796 performance/stuck off from P0797 stuck on and P0798 electrical before choosing the next test branch.
• 3

  Verify Fluid Level, Specification, and Evidence

  Hydraulic control cannot be judged until the fluid state is checked correctly.

  • Follow the exact temperature, selector, standpipe, dipstick, or overflow procedure; never use a universal level method.
  • Identify leaks, foaming, metal, clutch material, coolant, burnt odor, or incorrect fluid; color alone proves little.
  • Do not power-flush a slipping or debris-filled transmission unless the manufacturer procedure specifically directs it.
• 4

  Prove the Electrical Command Path

  A performance code is not permission to skip the circuit because solenoid current still creates hydraulic force.

  • Map solenoid C; verify feeds, grounds, TCM location, case connector, pin fit, chafing, and fluid intrusion.
  • Test resistance, voltage drop, current, and duty cycle only under OEM conditions; some faults require hot testing.
  • If P0798 or a circuit fault is active, finish that electrical decision tree before opening the valve body.
• 5

  Compare Command, Pressure, Ratio, and Slip

  The central question is whether the transmission produces the expected hydraulic and mechanical result.

  • Graph solenoid command with available pressure, speeds, gear or ratio, slip, load, and temperature.
  • Use active tests only when the vehicle supports the named function and service information lists safe prerequisites.
  • If command changes without response, follow the hydraulic branch; if absent, check enable conditions, wiring, power, and TCM control.
• 6

  Inspect, Repair, Relearn, and Verify

  Let pan evidence and the OEM decision tree decide whether the repair stops at the valve body or continues internally.

  • Inspect the pan, filter, valve body, solenoid body, and clutch or CVT belt evidence only at the authorized step.
  • Repair the proven fluid, circuit, solenoid, hydraulic, internal, software, or controller cause.
  • Complete required filling, initialization, adaptation, drive learn, clearing, and a safe post-repair rescan.

How to Fix P0796

Repair the branch that fails the transmission-specific test: correct fluid level or specification and repair the leak; repair a mapped feed, ground, harness, terminal, or case connector; replace a proven serviceable solenoid or solenoid body; service or replace the valve body when hydraulic evidence directs it; repair a pump, sensor, clutch, CVT belt/pulley, or other internal fault only after inspection; or update, initialize, or replace a controller only at the final OEM decision point.

How to Clear or Reset P0796 Safely

Save the original TCM report before clearing anything. Repair the proven cause, refill and level the transmission at the specified temperature, complete required solenoid-body setup, valve-body initialization, clutch or pressure adaptation, and drive learn, then clear P0796 with a compatible scanner. Clearing P0796 does not repair lost hydraulic control. Verify the original event without forcing a slipping transmission through an unsafe road test.

P0796 vs P0776, P0797, P0798, P0868, and P0730

These codes can share symptoms but identify different diagnostic directions. Always read the exact suffix and manufacturer description.

A ratio or low-pressure companion can strengthen the hydraulic or internal branch, while P0798 moves the circuit test forward. A TCM MIL-request code such as P1700 means the underlying transmission codes still have to be read.

P0796 Diagnostic and Repair Costs

Access and repair scope vary from a connector to a complete transmission. Use local written quotes built from test results.

Separate diagnosis, fluid, wiring, valve-body parts, programming, adaptations, teardown, and verification. Compare rebuild and replacement warranties when internal damage is confirmed. P0796 alone is not an estimate.

Where P0796 Diagnosis Differs by Vehicle

Model, transmission code, suffix, fluid, symptom, and prerequisites limit every published example. Match them before adopting a repair.

GM PIP5771B is limited to listed trucks and transmissions. Mitsubishi's CVT belt branch applies only to the referenced revision. The Audi example separates performance from electrical codes, but its thresholds are not universal.

DIY Checks vs Transmission-Shop Work

A careful owner can save the all-module report, document symptoms and service history, inspect accessible leaks and connectors, confirm the correct fluid procedure, and compare supported live data without forcing a fault. Only open a sealed or level-controlled transmission with the correct tools and fluid plan.

Use a qualified transmission technician for severe slip, fail-safe driving, pressure-gauge work, pan debris interpretation, valve-body disassembly, programming, internal clutch or CVT repair, and any road test that cannot be performed safely.

How to Reduce the Chance of P0796 Returning

Use the exact fluid specification, service interval, fill temperature, and level method. Repair leaks and cooling problems promptly, avoid towing beyond the vehicle rating, and do not mix universal additives into an unknown transmission. Complete required adaptations after qualifying repair.

Save a healthy post-repair scan with temperature, pressure or solenoid command, ratio, slip, and shift quality. A baseline makes an intermittent return easier to identify without immediately reopening the transmission.

Related iCARZONE Transmission Guides

Compare adjacent solenoid, ratio, range-sensor, and TCM-request codes before choosing a repair branch.

Frequently Asked Questions