P0933 on 2015-2017 Ford F-150: Hydraulic Pressure and Lead Frame Faults

What's Unique About the 2015-2017 Ford F-150

The 2015-2017 F-150, equipped with the 6R80 6-speed automatic transmission, has a widely documented and recalled issue with its internal molded lead frame. This single component houses multiple critical sensors, including the transmission range sensor and output speed sensor (OSS). While P0933 points to a pressure sensor issue, it's often a symptom of the entire lead frame failing due to heat and vibration, causing internal electrical connections to crack and leading to erratic signals that confuse the truck's computer. The most dangerous symptom of this failure is a sudden, violent downshift to a low gear at highway speeds, which can cause the rear wheels to lock up.

Symptoms You May Notice

• Sudden, harsh, and unexpected downshifts, sometimes to 1st or 2nd gear at highway speed.
• Check Engine Light and/or a wrench icon on the dashboard.
• Erratic or delayed gear shifting.
• Transmission stuck in one gear (limp mode).
• Loss of the gear position indicator (PRNDL) on the dash.
• Speedometer dropping to zero intermittently.
• Vehicle may not start if it cannot determine it is in Park or Neutral because the Transmission Range Sensor on the lead frame has failed.

Most Likely Causes

1. Failed Molded Lead Frame (Conductor Plate) 🔴 High Probability The original lead frame design is susceptible to failure from heat cycles and vibration, causing internal electrical connections for the sensors to crack. This is a well-documented issue leading to Ford Customer Satisfaction Program 19N01, which extended the warranty on this part to 10 years or 150,000 miles.
   How to confirm: A professional scan tool can check for other codes stored alongside P0933, such as P0720, P0722, or P0731, which strongly indicate lead frame failure. Monitoring the Output Shaft Speed (OSS) PID with a scan tool will often show the speed dropping to zero when the fault occurs.
   Typical fix: Replace the molded lead frame inside the transmission oil pan, which is attached to the valve body. The updated Ford part should be used. 🎬 Watch: Step-by-step lead frame replacement for P0720 and P0722 codes. This is a one-time repair under Ford's extended warranty program if the vehicle qualifies.
   Est. part cost: $150-$300
2. Low or Contaminated Transmission Fluid 🟡 Medium Probability The 6R80 transmission is known to contaminate its fluid relatively quickly. Old, contaminated fluid can affect hydraulic pressure and the function of sensitive components like solenoids and sensors.
   How to confirm: Check the transmission fluid level and condition via the service plug. The fluid should be at the correct level, red in color (Motorcraft MERCON LV), and not smell burnt. Dark, burnt, or fluid with excessive metallic particles indicates a problem.
   Typical fix: Perform a transmission fluid and filter change using the correct MERCON LV fluid. If the fluid is heavily contaminated, a full flush may be needed, but this can sometimes worsen issues in high-mileage transmissions.
   Est. part cost: $75-$150
3. Faulty Valve Body or Solenoids ⚪ Low Probability
   How to confirm: This requires advanced diagnostics with a scan tool that can command individual solenoids and monitor pressure response. It is typically diagnosed after the lead frame and fluid have been ruled out. TSB SSM 46451 notes an updated overhaul procedure for the main control valve body.
   Typical fix: Replace the specific faulty solenoid or the entire valve body assembly.
   Est. part cost: $300-$800

Rare But Worth Checking

• Wiring Harness Damage: Damage to the external transmission wiring harness can mimic internal faults. Always inspect the wiring leading to the main transmission connector for chafing, corrosion, or damage before condemning internal parts.
• Powertrain Control Module (PCM) Fault: In very rare cases, the vehicle's main computer can fail. This should only be considered after all other possibilities, including the lead frame and wiring, have been exhaustively checked. Recalls like 19S07 involved reprogramming the PCM to prevent downshifts even if the lead frame sensor failed.

Diagnosis Steps

1. Scan the vehicle for all stored trouble codes. Note any codes that accompany P0933, especially P0720, P0722, or P0731, as these are specifically mentioned in Ford's service programs for lead frame failure.
2. Check for any open recalls or customer satisfaction programs for your vehicle's VIN on the NHTSA or Ford owner website. Specifically look for recall 19S07 and Customer Satisfaction Program 19N01.
3. Check the transmission fluid level and condition. Low, burnt, or contaminated fluid can cause pressure issues. Ensure the correct Motorcraft MERCON LV fluid is used.
4. Inspect the main transmission wiring harness and connector for any visible damage, corrosion, or loose connections.
5. Using an advanced scan tool (like FORScan for Fords), monitor live data for Transmission Fluid Pressure, Output Shaft Speed (OSS), and Turbine Shaft Speed (TSS) while driving. Look for erratic readings or sudden dropouts of the OSS signal to zero, which is a classic sign of a failing lead frame.
6. If lead frame failure is confirmed by codes and live data, the next step is to drop the transmission pan for inspection and replacement of the lead frame assembly. Under program 19N01, this may be covered by Ford.

Parts You'll Likely Need

• Molded Lead Frame / Conductor Plate (OEM #AL3Z-7G276-D) — This is the root cause of the vast majority of P0933-related issues on this truck. It is a known failure point and has been subject to recalls and extended warranties. The part has been updated several times; AL3Z-7G276-D is a common replacement.
  Trusted brands: Motorcraft, Dorman
  OEM price range: $150-$250
  Aftermarket price range: $100-$200
• Transmission Pan Gasket (OEM #BL3Z-7A191-C) — Required when dropping the transmission pan to access the lead frame. It is non-reusable.
  Trusted brands: Motorcraft, Fel-Pro
  OEM price range: $30-$50
  Aftermarket price range: $20-$40
• Transmission Filter (OEM #BL3Z-7A098-A) — Should be replaced whenever the transmission pan is removed for service.
  Trusted brands: Motorcraft
  OEM price range: $25-$40
  Aftermarket price range: $15-$30
• Motorcraft MERCON LV Automatic Transmission Fluid (OEM #XT-10-QLVC) — The transmission will need to be refilled with the correct type of fluid after the repair. Approximately 8-9 quarts are needed for a pan-drop service.
  Trusted brands: Motorcraft
  OEM price range: $8-$12 per quart
• Transmission Bulkhead Connector Sleeve (OEM #AL3Z-7G391-A) — This seal where the wiring passes into the transmission is a common leak point and should be replaced whenever the lead frame is serviced.
  Trusted brands: Motorcraft
  OEM price range: $15-$25
  Aftermarket price range: $10-$20

Related Codes That Often Appear With This One

• P0720 — Output Speed Sensor (OSS) Circuit Malfunction. The OSS is located on the same lead frame and its failure is the primary cause of the sudden downshifts.
• P0722 — Output Speed Sensor (OSS) Circuit No Signal. This is another common code indicating the lead frame has failed and lost signal completely.
• P0731 — Gear 1 Incorrect Ratio. This code can be triggered when the transmission downshifts unexpectedly to 1st gear due to the OSS failure.
• P0707 — Transmission Range Sensor Circuit Low Input. The range sensor (TRS), which tells the computer if the truck is in Park, Reverse, Neutral, or Drive, is also part of the lead frame assembly.

Technical Service Bulletins (TSBs) & Recalls

• Customer Satisfaction Program 19N01: Extended warranty coverage for the molded lead frame to 10 years/150,000 miles for specific DTCs.

Platform-Specific Known Issues

• Ford issued Customer Satisfaction Program 19N01 which extended the warranty on the molded lead frame for certain F-150s to 10 years or 150,000 miles. This covered replacement if specific DTCs like P0720, P0722, or P0731 were present.
• NHTSA opened a preliminary evaluation (PE25-001) and then an engineering analysis into the 2015-2017 F-150s for this exact issue, following earlier recalls on 2011-2014 models. This investigation noted that the failure mechanism was degradation of electrical connections from thermal cycling and vibration.

Mechanic-Grade Diagnostic Values

• Shift Solenoid E (SSE) Resistance — expected: Approx. 18 Ohms. Failure: A reading significantly higher or lower than 18 Ohms indicates a faulty solenoid.
• Variable Force Solenoid (VFS) Resistance — expected: 10 - 18 Ohms. Failure: Readings outside this range suggest a failing VFS solenoid.
• Hydraulic Pressure Sensor Voltage (General Test) — expected: 5V reference, 0V ground, and a variable voltage on the signal line with key on.. Failure: Measuring 5V on the ground line indicates an open ground. Measuring over 4.5V on the signal line with the sensor connected suggests an internal sensor short.
• Torque Converter Clutch (TCC) Pressure (FORScan PID) — expected: Ranges from ~19 psi to ~37 psi during operation in one documented case.. Failure: While there is no official spec, one owner reported these values while diagnosing a shudder. Significantly lower pressure could indicate a problem.

Scan Tool Commands That Help

• FORScan: Live Data Monitoring (PIDs) — Use to monitor PIDs like 'OSS' (Output Shaft Speed), 'TSS' (Turbine Shaft Speed), 'TFT' (Transmission Fluid Temperature), and commanded vs. actual gear. A sudden drop of the OSS PID to zero during driving is a classic indicator of a failing lead frame.
• FORScan: Clear Transmission Adaptive Tables — After replacing the lead frame or valve body, clearing the adaptive learning tables is recommended. This forces the TCM to relearn shift points and clutch engagement pressures with the new components, which can resolve harsh or erratic shifting post-repair.
• Ford IDS (Dealer Tool): Solenoid Body Strategy Programming — If the entire valve body with solenoids is replaced, the new solenoid body's strategy and ID numbers (found on a tag on the valve body) must be programmed into the PCM/TCM. The lead frame itself does not require programming, but a valve body replacement does.

Wiring & Ground Locations

• Transmission Bulkhead Connector — On the passenger side of the transmission case, toward the rear. The external wiring harness plugs into it.. This is the single pass-through point for all electronic signals between the internal lead frame and the vehicle's wiring harness. A locking lever secures it. The internal sleeve and external connector o-rings are common leak points and should be replaced during a lead frame service.

Real Owner Repair Stories

• f150forum.com user (2016 F-150 4x4 XLT, 5.0L, 6R80 transmission) — Transmission going into 'limp mode', output shaft sensor error code stored.
  ❌ Tried (didn't work) The user went straight for diagnosis at a Ford dealer.
  ✅ What actually fixed it The Ford dealer diagnosed a failed lead frame and replaced it. The user reported the issue was resolved but was quoted a high price of $2200 for the repair.
• Reddit user r/f150 (2016 F-150 5.0L) — Slipping gears, but no codes stored initially.
  ❌ Tried (didn't work) Driving with the issue for 2-3 months while researching.
  ✅ What actually fixed it The owner performed a DIY replacement of the molded lead frame using OEM parts. The total cost for parts and fluid was approximately $300. The user reported the job was messy but straightforward and resolved the shifting problems.
• YouTube video by 'Nuts and Bolts with Tone' (Ford F-150 5.0L with 6R80 Transmission) — Codes for output speed sensor issues.
  ✅ What actually fixed it The video documents a complete replacement of the lead frame assembly. A key step shown is the fluid refill procedure, which involves an initial fill of 3.5 quarts, cycling through the gears, and then topping off the fluid with the engine running until it reaches the correct level on the dipstick.

OEM Part Supersession History

• AL3Z-7G276-A, AL3Z-7G276-B → AL3Z-7G276-D — The part has been revised to improve durability and prevent the cracking of internal electrical traces that caused the widespread failures.
  Heads up: The 'D' revision is the current recommended replacement for earlier versions and is backward compatible.

Model Year Variations Within This Range

• 2015-2017: While the 6R80 transmission was used in all three model years, some very late 2017 models could have been equipped with the newer 10-speed (10R80) transmission. It is crucial to verify which transmission the vehicle has. However, for the trucks equipped with the 6R80, there are no significant internal hardware differences related to this fault across the 2015-2017 range.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Frozen Door Latches 🔴 High — Very common in cold climates. Doors may not open from the outside or may not latch closed. (Ref: Customer Satisfaction Program 18N03 extends coverage for this repair through Oct 31, 2028.)
• Warped Dashboard 🟡 Low — Common on XL and XLT trim levels; the dash deforms and lifts near the defrost vents. (Ref: TSB 19-2041 (supersedes SSM 47270) outlines the replacement procedure for warrantable claims.)
• Adaptive Cruise Control Braking Erroneously 🟠 Medium — Can occur when passing large reflective vehicles, causing the truck to brake unexpectedly. (Ref: Recall 15S29 was issued to update the cruise control module software.)
• 2.7L EcoBoost Engine Oil Smoke on Startup 🟠 Medium — Some 2.7L engines may exhibit blue or white smoke after a cold soak due to oil entering the turbocharger. (Ref: TSB 19-2188 addresses this issue.)
• 5.0L V8 Bellhousing Rattle (2018-2019) 🟡 Low — Affects some 2018-2019 models with the 5.0L engine, causing a metallic rattle due to torque converter stud contact. (Ref: TSB 19-2358 provides the fix by replacing the engine-to-transmission spacer plate.)

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: For this specific repair, buying a used molded lead frame is NOT recommended. The part is a known high-failure item due to a design defect that is exacerbated by heat cycles. A used part from a junkyard has an unknown history and is likely to fail in the same manner as the original.

OEM-only on this vehicle (don't cheap out):

• Molded Lead Frame

Aftermarket brands forum-validated for this vehicle:

• Motorcraft (OEM)
• Circuit Board Medics (Remanufactured OEM with potential improvements)

Brands owners have reported issues with on this vehicle:

• Dorman: While some owners have used the Dorman replacement out of necessity when the OEM part was unavailable, with mixed short-term success, the general consensus in forums is to avoid it if the Motorcraft part is available due to concerns about longevity.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0720 — Output Speed Sensor (OSS) Circuit Malfunction. This code is a primary indicator of the common lead frame failure, as the OSS is integrated into the lead frame assembly. It is specifically mentioned in Ford's Customer Satisfaction Program 19N01.
• P0722 — Output Speed Sensor (OSS) Circuit No Signal. Like P0720, this code points directly to a failure of the OSS sensor on the molded lead frame, which causes the powertrain control module to lose the vehicle speed signal from the transmission.
• P0731 — Gear 1 Incorrect Ratio. This code can be set as a consequence of the lead frame failure. When the computer receives an incorrect speed signal from the failing OSS, it can misinterpret gear ratios and trigger this code. It is also listed in Ford's 19N01 program.
• P0715 — Turbine/Input Shaft Speed Sensor (TSS) Circuit Malfunction. The TSS is also located on the molded lead frame. A failure of the lead frame's internal circuitry can affect the TSS signal, often causing this code to appear alongside OSS codes.
• P0705 — Transmission Range Sensor (TRS) Circuit Malfunction. The TRS is another component integrated into the molded lead frame. Its failure can prevent the vehicle from starting and is caused by the same internal cracks in the lead frame that trigger other related codes.

Frequently Asked Questions