P0716 on 2014-2021 Ram 1500: Input Shaft Speed Sensor Performance Fixes

What's Unique About the 2014-2021 Ram 1500

The 2014-2021 Ram 1500 primarily uses the ZF 8-speed automatic transmission (e.g., 8HP70, 8HP75). For this platform, P0716 is a well-documented issue. 🎬 Watch: Understanding the turbine shaft speed sensor performance code. A common point of failure is the internal transmission wiring harness, often called the conductor plate or lead frame, which integrates the input and output speed sensors. This entire assembly is located inside the transmission, mounted to the valve body, and is susceptible to heat and fluid contamination, requiring significant labor to replace. 🎬 See this walkthrough on removing the 8HP70 TCM assembly. Manufacturer Technical Service Bulletins (TSBs) often group this code with others, suggesting that software updates can sometimes resolve what appears to be a sensor issue, but hardware failure is more common.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Generation note: This range covers the end of the 4th generation (2014-2018) and the start of the 5th generation (2019-2021). Both generations use variants of the ZF 8-speed automatic transmission (like the 8HP70, 8HP75), and this code is common to both due to the shared transmission architecture. TSB S2621000003 REV. A specifically lists both the DS (4th gen) and DT (5th gen) Ram 1500s as affected.

Symptoms You May Notice

• Check Engine Light or Transmission Warning Light is on.
• Harsh, erratic, or delayed shifting.
• Transmission gets stuck in one gear (limp mode).
• Engine RPMs fluctuate at a steady speed.
• Vehicle may hesitate or have reduced acceleration.
• Speedometer may malfunction or behave erratically.

Most Likely Causes

1. Faulty Input Shaft Speed (ISS) Sensor / Internal Harness 🔴 High Probability → Shop Drive Shaft Sensor The sensor is integrated into the internal wiring harness (conductor plate) inside the transmission, exposed to constant heat cycles and fluid. This environment can cause the plastic and wiring to become brittle and fail, or the sensor's electronics to degrade.
   How to confirm: Use a professional scan tool to monitor the Input Speed Sensor data in real-time. If the reading is zero, erratic, or jumps unexpectedly while engine RPM is steady, the sensor or its circuit is faulty. The sensor itself cannot be replaced individually; the entire harness assembly must be changed.
   Typical fix: Replace the internal transmission wiring harness/conductor plate assembly. This involves draining the transmission fluid, removing the pan, and dropping the valve body to access the part.
   Est. part cost: $200-$400
2. Low or Contaminated Transmission Fluid 🟡 Medium Probability → Shop Transmission Assembly The ZF 8-speed is highly sensitive to fluid level and condition. The correct fluid is Mopar ZF 8&9 Speed ATF or an equivalent like Lifeguard 8. Low fluid can cause pressure issues and aeration, while old, contaminated fluid can interfere with sensor operation or cause internal wear.
   How to confirm: Check the transmission fluid level and condition according to the manufacturer's procedure, which must be done at a specific operating temperature. Fluid with a burnt odor is normal for this transmission, but fluid containing excessive metal particles indicates a larger problem.
   Typical fix: Perform a transmission fluid and filter change using the correct OEM-spec fluid. If significant metal debris is found, a transmission rebuild may be necessary.
   Est. part cost: $100-$250
3. Damaged Internal Wiring Harness or Connectors 🟡 Medium Probability → Shop Transmission Wiring Harness This is the same as the primary cause. The wiring harness inside the transmission, often called the lead frame or conductor plate, can become brittle from constant heat cycles. The connector pins for the speed sensor can also fail, leading to an intermittent signal.
   How to confirm: A definitive diagnosis requires visual inspection of the harness and connectors when the transmission pan and valve body are removed. Check for broken wires, corroded pins, or a loose fit.
   Typical fix: Replace the internal transmission wiring harness/lead frame assembly. This part is not typically repaired, only replaced.
   Est. part cost: $200-$400
4. Outdated Transmission Control Module (TCM) Software ⚪ Low Probability → Shop Transmission Assembly Manufacturers release software updates to fix bugs and improve transmission logic. TSB 21-011-20 for the 2019 Ram 1500 specifically lists P0716 as a code that can be addressed by a TCM software update, along with various shift quality complaints.
   How to confirm: A dealership or qualified shop can check for available TCM software updates using the vehicle's VIN.
   Typical fix: Update or re-flash the TCM with the latest software. This is often attempted before more invasive mechanical repairs.
   Est. part cost: $100-$250

Rare But Worth Checking

• Failing Transmission Control Module (TCM) or Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is uncommon, but if the sensor, wiring, and fluid are all confirmed to be good, the module itself could be misinterpreting the signal. This should be the last item to check after all other possibilities are exhausted.
• Internal Mechanical Transmission Failure: → Shop Transmission Assembly Excessive metal debris on the magnetic tip of the speed sensor can indicate a more serious internal problem, like clutch or bearing failure. The debris disrupts the sensor's magnetic field, causing an erratic signal. TSB S2621000003 notes that fine metallic dust is normal wear, but larger debris indicates a problem.
• Weak or Failing Battery: Some owners on forums for platform mates like the Jeep Grand Cherokee have reported that a weak battery can cause various random electronic issues, including transmission fault codes. Before extensive transmission work, it's wise to test the battery and charging system.

Diagnosis Steps

1. Check and document any other stored trouble codes with a quality OBD-II scanner.
2. Check the transmission fluid level and condition. Ensure it is clean, at the correct level per the manufacturer's temperature-specific procedure, and does not contain excessive metal debris.
3. Use a scan tool to monitor live data from the Input Shaft Speed Sensor (PID 0x1E72). Watch for erratic readings, dropouts to zero, or a value that doesn't correlate with engine RPM while driving.
4. Check for any available Technical Service Bulletins (TSBs) related to P0716 or transmission symptoms for your specific VIN. TSBs like 21-011-20 may recommend a software update as the first step.
5. Inspect the external transmission wiring harness and connectors for any visible damage, corrosion, or loose connections.
6. If external checks pass, the next step is internal inspection. This requires draining the fluid, removing the transmission pan, and inspecting the internal wiring harness (conductor plate) and the sensor itself.
7. Remove the input speed sensor (as part of the harness) and check its magnetic tip for metal shavings, which would indicate a larger mechanical issue.
8. If the harness is being replaced, it is common practice to also service or replace the valve body solenoids, or the entire valve body assembly, depending on mileage and symptoms.
9. If a new harness/sensor does not fix the issue, and software is up to date, the problem may lie with the TCM itself.

Parts You'll Likely Need

• Transmission Conductor Plate / Internal Harness Assembly — This is the most frequent point of failure for a P0716 code. The sensor itself fails or the integrated wiring becomes faulty, requiring replacement of the entire assembly, which is also known as a lead frame.
  Trusted brands: Mopar, ZF
  OEM price range: $250-$400
  Aftermarket price range: $150-$300
• Transmission Fluid and Filter/Pan Gasket Kit (OEM #68225344AA (Service Kit example))

Related Codes That Often Appear With This One

• P0717 — This code for 'Input/Turbine Speed Sensor 'A' Circuit No Signal' often appears with P0716, indicating a complete loss of signal versus an erratic one.
• P0721 — This code relates to the Output Shaft Speed Sensor performance. It can be set along with P0716 if the TCM sees a mismatch between input and output speeds. TSB 21-011-20 lists both codes together.
• P0733 — This code for 'Gear 3 Incorrect Ratio' is a direct consequence of the TCM not having reliable speed sensor data to confirm proper gear engagement. TSB 21-011-20 and S2621000003 both list this code alongside P0716.

Technical Service Bulletins (TSBs) & Recalls

• 21-011-20: Flash: Transmission Control Module (TCM) Updates for 2019 Ram 1500.
• S2621000003 REV. A: Diagnostic guidance for multiple 8-speed transmission codes including P0716 across many Stellantis vehicles.
• 21-009-20: Another TCM flash bulletin for 2019 models that includes P0716. [NHTSA Data]

Platform-Specific Known Issues

• TSB S2621000003 REV. A: This broad TSB covers numerous Chrysler/Dodge/Jeep/Ram vehicles with 8-speed transmissions (8HP70, 8HP75, etc.) and lists P0716 as a known fault code. It advises against replacing the transmission for just this code and notes that a burnt fluid smell is normal. It suggests following other specific TSBs for certain gear ratio codes first before considering a valve body replacement.
• TSB 21-011-20: Specifically for 2019 Ram 1500s with the 5.7L eTorque and 8HP75 transmission, this TSB involves reprogramming the TCM to fix a list of potential DTCs, including P0716. It also addresses various shift quality issues like hunting for gears or harsh downshifts.
• Owner Forum Experience: A user on Reddit with a 2015 Ram 1500 reported a P0716 code that appeared after a transmission fluid and filter service. Clearing the code provided a temporary fix, indicating the intermittent nature of the fault. This highlights that the issue can appear suddenly even on a maintained vehicle.

Mechanic-Grade Diagnostic Values

• Input Speed Sensor Signal Voltage (Live Data) — expected: ~0.5 V at idle, rising proportionally with engine speed to 4.0-4.5 V at wide-open throttle.. Failure: Readings that are static, zero, erratic, or outside the 0.5-4.5V range.
• Speed Sensor Ground Circuit Voltage — expected: Below 0.5 volts.. Failure: Voltage above 0.5 volts indicates a short to voltage in the ground circuit.
• Wiring Harness Continuity — expected: 0.5 Ω or lower resistance.. Failure: Higher resistance indicates a problem in the wiring.

Scan Tool Commands That Help

• wiTECH or equivalent: Monitor Input Speed Sensor RPM — During diagnosis, compare the Input Speed Sensor RPM to Engine RPM and Output Speed Sensor RPM. With the vehicle in gear and stopped, Input Speed RPM should be very close to Engine RPM. Erratic readings or dropouts indicate a fault.
• wiTECH or equivalent: Transmission Quick Learn / Re-learn — After replacing the valve body, conductor plate, or solenoids, a re-learn procedure is necessary to reset adaptive values and ensure proper shift timing.
• Miller tool #8333 (Transmission Simulator): Simulate Sensor RPM — In advanced diagnostics, this special tool can be used to send a known RPM signal (e.g., 3000 RPM) to the TCM to verify if the module and wiring are processing the signal correctly, isolating the fault to the sensor itself.

Wiring & Ground Locations

• Main Transmission Connector (8HP) — On the passenger side of the transmission housing.. This is the main external connection point for all internal electronics, including the input speed sensor. The pins for CAN bus and power pass through here. A pinout diagram is needed to test continuity and voltage for the sensor circuit.
• Transmission Ground Strap — Typically a braided copper cable running from the transmission bell housing to the firewall or frame on the passenger side of the engine bay.. A poor or missing ground can cause a host of electrical issues, including erratic sensor readings and incorrect TCM behavior. Forum users have reported strange shifting behavior that was resolved by fixing a faulty ground strap.
• PCM C4 Harness Connector — At the Powertrain Control Module (PCM).. This is the connector where the signal from the input speed sensor ultimately arrives. Service manuals specify testing voltage and resistance at this connector (using a breakout tool like Miller #8815) to diagnose circuit integrity without damaging the PCM terminals.

Real Owner Repair Stories

• RamForum.com user (2013 Ram 4.7L) — Extremely hard shifting, engine hitting a 'brick wall' at 4-4.5K RPMs, CVI values climbing past 75. Shifting would improve temporarily when the A/C was turned on.
  ❌ Tried (didn't work) Dealer performed a 'quicklearn' which only helped for about 50 miles.
  ✅ What actually fixed it The user found a ground strap on the floor of their truck around the time the issues started. The symptoms strongly pointed to a grounding issue, which was causing erratic electronic behavior affecting transmission performance.

OEM Part Supersession History

• Not specified → 68225344AA — This part number is a service kit that includes the transmission oil pan, integrated filter, gasket, and bolts for various 8-speed transmissions like the 8HP45, 845RE, and 850RE.
  Heads up: This is a pan and filter kit, not the conductor plate itself. However, it is required for any repair that involves dropping the valve body, such as replacing the conductor plate/harness where the P0716 sensor is located.