P0722 on 2005-2010 Chevrolet Cobalt: Output Speed Sensor Failure Causes and Fixes

What's Unique About the 2005-2010 Chevrolet Cobalt

A unique and critical issue on the 2005-2010 Cobalt is that a P0722 code will often cause the electric power steering to fail, displaying a "Power Steering" message on the dashboard. The power steering control module requires a valid vehicle speed signal from the OSS to function correctly. When the signal is lost, the system defaults to a much heavier manual steering mode, which can be alarming and dangerous at low speeds. This specific symptom is also common on its platform mates, the Pontiac G5 and Chevrolet HHR.

Symptoms You May Notice

• Check Engine Light is on
• Harsh, erratic, or delayed gear shifting.
• Speedometer reads 0 MPH or behaves erratically.
• Cruise control does not work.
• "Power Steering" message appears on the driver information center, with a sudden increase in steering effort.
• Transmission may be stuck in a single gear (limp mode).
• Possible engine stalling when coming to a stop.
• Traction Control (TC) light may illuminate.

Most Likely Causes

1. Failed Output Speed Sensor (OSS) 🔴 High Probability The sensor is an electronic component mounted on the transmission case, exposed to constant heat and vibration, which leads to eventual failure.
   How to confirm: Use a scan tool to monitor live data for Output Shaft Speed. If it reads 0 RPM while the vehicle is moving, the sensor or its circuit is faulty. The sensor is located on the back side of the transmission, near the firewall, above the passenger-side drive axle. You can also test the sensor's internal resistance with a multimeter; an open or shorted circuit indicates failure.
   Typical fix: Replace the Output Speed Sensor and its O-ring. 🎬 Watch: Step-by-step output speed sensor replacement guide The area should be cleaned thoroughly before removing the old sensor to prevent debris from entering the transmission.
   Est. part cost: $15-$50
2. Damaged Wiring or Corroded Connector 🟡 Medium Probability The wiring harness to the sensor is located underneath the vehicle and is susceptible to damage from road debris, heat from the exhaust, and moisture causing corrosion in the connector pins. Rodents have also been known to chew on these wires.
   How to confirm: Visually inspect the wiring harness leading to the OSS for any signs of fraying, melting, or breaks. Unplug the connector and check for corrosion, moisture, or bent/broken pins. The two wires for the sensor are typically violet and yellow.
   Typical fix: Repair the damaged section of wire or replace the connector pigtail.
   Est. part cost: $10-$30
3. Low or Contaminated Transmission Fluid ⚪ Low Probability → Shop Transmission Assembly Dirty fluid can contain metallic particles that accumulate on the magnetic tip of the speed sensor, disrupting its ability to generate a signal. While possible, this is less common than outright sensor or wiring failure on the Cobalt.
   How to confirm: Check the transmission fluid level and condition. If the fluid is dark, burnt-smelling, or contains visible debris, it needs to be changed.
   Typical fix: Perform a transmission fluid and filter change.
   Est. part cost: $50-$120

Rare But Worth Checking

• Faulty Transmission Control Module (TCM) or Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is rare and should only be considered after the sensor and wiring have been thoroughly tested and ruled out. Sometimes other transmission codes will be present if the TCM is failing. Some owners have reported that adding an extra ground wire to the TCM can resolve intermittent issues, though this is not an official fix.
• Internal Transmission Failure: → Shop Transmission Assembly In rare cases, an internal mechanical issue like a faulty valve body or shift solenoid could cause this code, but it is almost always accompanied by other transmission-specific trouble codes. NHTSA ODI #11686435 describes a situation where P0722 and P0700 persisted even after a valve body replacement, leading to a suspected torque converter issue.

Diagnosis Steps

1. Check the transmission fluid level and condition. Top off or change if necessary.
2. Connect an OBD-II scanner and check for any other transmission-related codes. Note the freeze-frame data if available.
3. Use the scanner's live data function to monitor the Output Speed Sensor (OSS) signal while driving slowly. The reading should increase smoothly with vehicle speed. If it remains at 0, proceed with testing.
4. Locate the OSS on the transmission case. It is typically on the back side, above the passenger-side drive axle. Visually inspect the sensor's connector and wiring (typically violet and yellow wires) for any obvious damage, corrosion, or loose connections.
5. Disconnect the sensor and use a multimeter to test for proper voltage and ground at the connector with the key on.
6. If power and ground are present, test the sensor itself. You can check its internal resistance with a multimeter. Compare the reading to the manufacturer's specification. An infinite or zero reading indicates a failed sensor.
7. If the sensor and wiring test good, the problem may be with the TCM or an internal transmission issue, which typically requires professional diagnosis.

Parts You'll Likely Need

• Transmission Output Speed Sensor (OEM #ACDelco 24207507) — This sensor is the most common failure point for a P0722 code.
  Trusted brands: ACDelco, Delphi, Dorman, NGK
  OEM price range: $30-$50
  Aftermarket price range: $15-$40

Related Codes That Often Appear With This One

• P0700 — P0700 is a generic code that means the Transmission Control Module (TCM) has requested the check engine light to be turned on. It is often set alongside more specific transmission codes like P0722.

Platform-Specific Known Issues

• A known issue for this platform is the loss of electric power steering assist when the P0722 code is active, as the power steering module loses its vehicle speed input.
• The 2005-2010 Cobalt was subject to a major safety recall for a faulty electric power steering motor (GM Recall No. 10V073000). While a separate issue, a P0722 code can produce identical symptoms of power steering loss, leading to potential misdiagnosis. It's crucial to diagnose the P0722 code first before assuming the power steering motor itself has failed.
🎬 See how to fix the Cobalt power steering warning

Technical Service Bulletins (TSBs) & Recalls

• Bulletin #PIP5473: This manufacturer bulletin notes that technicians may find P0722 along with other speed sensor codes like P0721 or P0717, and advises following published Service Information diagnostics first.
• GM Recall No. 10V073000: As noted above, this recall addresses the electric power steering motor, which can fail independently but mimics the steering loss caused by a P0722 speed sensor fault.

Mechanic-Grade Diagnostic Values

• Conditions for Setting DTC P0722 — expected: The TCM must see an output speed of less than 200 RPM for 4.5 seconds while the input speed is between 1,500-5,000 RPM and the transmission is in a drive gear.. Failure: Meeting these conditions will trigger the P0722 code.

Scan Tool Commands That Help

• Tech2/GDS2: TCM Relearn/Reset — After replacing the TCM, a relearn procedure may be necessary. However, for a simple OSS replacement, a battery disconnect for 10-15 minutes is usually sufficient to clear adaptive memory.

Wiring & Ground Locations

• G105 — On top of the transmission case, often underneath the main wiring harness and near the radiator hose connection to the engine block.. This is a primary ground point for multiple systems, including the TCM on some schematics. Corrosion or breakage at this point can cause a host of intermittent electrical problems, including loss of sensor signals and communication errors that can mimic a failed sensor or module. 🎬 Watch: Diagnosing Cobalt ground issues and U101 codes
• OSS Connector — On the back side of the transmission, near the firewall, above the passenger-side drive axle.. This is the direct connection point for the sensor. The two wires are typically violet and yellow. Damage or corrosion here will cause a direct loss of signal and set P0722.

Real Owner Repair Stories

• YouTube channel 'THIS IS YOUR TRANSMISSION' (Chevrolet Cobalt (year not specified, but within 2005-2010 range)) — No start, speedometer not working, communication code U101 with TCM.
  ❌ Tried (didn't work) Initial inspection of wiring harness for chafing near the engine.
  ✅ What actually fixed it The ground wires inside the G105 ground terminal on top of the transmission had corroded and broken off inside the lug. Repairing the ground terminal by cleaning the connection point and installing a new terminal lug restored vehicle function and communication with the TCM.
• CobaltSS.net user 'Spawne32' (2005 Cobalt 2.2L) — After a long drive, cruise control failed, speedometer dropped to 0 MPH, and shifts became rough. Codes P0722, P0700, and P0171 were present.
  ❌ Tried (didn't work) Replacing the Output Speed Sensor with an aftermarket part from AutoZone., Wiggling the wiring harness., Resetting the computer by disconnecting the battery.
  ✅ What actually fixed it The user was advised to check for voltage at the sensor connector with a multimeter and to check all related fuses, particularly for the cruise control system, before further diagnosis. The final resolution was not posted in the thread, but the diagnostic path highlights that simply replacing the sensor is not always the fix.
• NHTSA ODI #10926749 — An owner reported that even after replacing the speed sensor, the vehicle continued to throw codes P0722 and P0700, along with P0597 and idle-related codes, requiring a dealership diagnostic.
• NHTSA ODI #11366176 — One report describes a vehicle that shakes and makes a clacking noise with the Electronic Stability Control (ESC) and Traction Control turning off, accompanied by code P0722 and several solenoid-related codes.
• NHTSA ODI #11496008 — An owner noted receiving a "no signal" reading for the speed sensor (P0722) alongside a pressure solenoid performance code (P0796).

OEM Part Supersession History

• 24235862 → 24207507 — Standard part consolidation and potential minor design/material improvements over the production run.

Model Year Variations Within This Range

• 2009-2010: The 2.2L L61 engine was replaced by the 2.2L LAP engine, which featured variable valve timing for improved power and fuel economy. While this doesn't directly change the P0722 diagnosis, the engine management system is more advanced.
• 2010: Stability control became a standard feature. This system heavily relies on accurate wheel speed and vehicle speed data to function, making the OSS signal even more critical.

Diagnostic Flowchart

Other Known Issues on This Vehicle

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

• Faulty Ignition Switch 🔴 High — Extremely common across all model years. Subject of a massive and well-publicized safety recall (e.g., GM Recall 14V047000). (Ref: Multiple Recalls (e.g., 14V047000))
• Electric Power Steering (EPS) Motor Failure 🔴 High — Very common, leading to a sudden loss of power assist. Separate from the P0722 issue but can present with identical symptoms. Subject to a major recall. (Ref: Recall 10V073000)
• Premature Front Lower Control Arm Bushing Failure 🟠 Medium — Commonly fails well under 100,000 miles, causing a distinct clunking noise from the front suspension over bumps.
• Fuel Pump Module Leaks 🔴 High — The plastic supply or return port on the fuel pump module can crack, causing a fuel leak and fire hazard. Primarily affects vehicles in warmer climates. (Ref: Recall 09V419000)
• Faulty Ignition Control Module (ICM) 🟠 Medium — A known weak point on the 2.2L Ecotec, especially 2005-2006 models. Failure often occurs when the engine is hot, causing misfires (e.g., P0363).
• Faulty Shifter Cable / Bushing 🟡 Low — The cable or its retaining bushing can fail, preventing the car from going into the selected gear or causing the ignition key to become stuck.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: For this repair, a used part is generally not recommended. The primary failure component, the Output Speed Sensor, is an inexpensive electronic part that is subject to wear from heat and vibration. The cost savings of a used sensor are minimal and not worth the risk of premature failure.

Donor-vehicle mileage cap: roughly under 80000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• If considering a used wiring harness, inspect thoroughly for any signs of brittleness, melting, or previous repairs.
• For a used TCM, ensure the part number matches exactly and be prepared for potential reprogramming costs.

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

• Transmission Control Module (TCM) - While a used one can work, it often requires professional programming (VIN matching) to function correctly with the vehicle's other modules. An OEM or professionally remanufactured unit is the safest bet.

Aftermarket brands forum-validated for this vehicle:

• ACDelco (OEM)
• Delphi
• NGK/NTK
• Dorman

Brands owners have reported issues with on this vehicle:

• No-name, unbranded sensors sold at extremely low prices on marketplace websites can have high failure rates and should be avoided.

Real Owner Stories

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

Related OBD-II Codes

• P0700 — Transmission Control System Malfunction — often appears as an informative code alongside P0722 indicating the TCM has requested MIL illumination.
• P0171 — System Too Lean — observed in owner reports alongside P0722 during multi-system failures on the 2.2L platform.
• P0363 — Misfire Detected - Fueling Disabled — related to Faulty Ignition Control Module (ICM) failures common on the 2.2L Ecotec engine.
• UXXXX — Network communication codes may occur when the power steering module or TCM loses the vehicle speed signal provided by the OSS.

Frequently Asked Questions