C0710 on 2008-2012 GMC Savana: StabiliTrak and Steering Sensor Faults Explained

What's Unique About the 2008-2012 Gmc SAVANA

On this generation of GMC Savana and its platform mates (like the Chevrolet Express, Silverado, and Tahoe), code C0710 is notoriously caused by a poor electrical connection at the steering angle sensor. GM issued a specific Technical Service Bulletin (PI0639C) detailing that the issue stems from fretting corrosion on the connector terminals and excessive clearance in the connector housing, which allows movement. The official fix often does not require replacing the sensor itself, and the TSB explicitly states, "DO NOT replace the steering position sensor for this condition" until the connector has been serviced.

Diagnostic Flowchart

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

Symptoms You May Notice

• "Service StabiliTrak" message on the Driver Information Center (DIC)
• StabiliTrak/Traction Control indicator light is on
• Stability control system is disabled
• Warning light may appear randomly and intermittently

Most Likely Causes

1. Poor Connection at Steering Angle Sensor Connector 🔴 High Probability → Shop Steering Angle Sensor GM TSB #PI0639C directly identifies fretting corrosion and excessive clearance in the connector as the primary cause for this platform. The movement of the connector, sometimes from normal steering or column adjustment, leads to a high-resistance condition that interrupts the signal.
   How to confirm: Visually inspect the steering angle sensor connector for looseness, and look for small dark smudges (fretting corrosion) on the terminals. Use a scan tool with live data graphing to monitor the sensor's voltage or angle. Wiggle the connector or turn the steering wheel; if the signal drops out, spikes, or becomes noisy, the connection is the fault.
   Typical fix: Follow the TSB PI0639C procedure: disconnect the connector, clean the terminals on both sides with a dedicated nylon brush, apply a small amount of dielectric lubricant (GM P/N 12377900), and add an adhesive shim (Kent P40100) to the flat surface of the male connector body to eliminate movement.
   Est. part cost: $5-$20
2. Faulty Steering Angle Sensor (SAS) 🟡 Medium Probability → Shop Steering Angle Sensor
   How to confirm: If the connector service does not resolve the code, the sensor itself may have failed. Use a scan tool with live data to monitor the steering angle sensor's output while turning the steering wheel lock-to-lock. The degree readings should change smoothly from approximately -500 to +500 degrees without any dropouts, freezing, or erratic jumps. A lab scope can provide a more definitive diagnosis by showing noise in the signal.
   Typical fix: Replace the steering angle sensor. This often requires removing the lower dash panels and steering column covers. The new sensor must be calibrated using a compatible scan tool. 🎬 See this step-by-step steering wheel sensor replacement guide.
   Est. part cost: $60-$150
3. Incorrect Steering Angle Calibration ⚪ Low Probability
   How to confirm: This can occur after a wheel alignment, battery replacement, or replacement of steering/suspension components. If the steering wheel is not physically centered when the wheels are straight, the sensor's reading will be implausible, triggering the code. A scan tool can show the current calibration value, which should be near 0 degrees when driving straight.
   Typical fix: Perform a steering angle sensor calibration using a compatible professional scan tool.
   Est. part cost: $0

Rare But Worth Checking

• Damaged Wiring Harness: While less common than connector issues, the wiring between the sensor and the EBCM can be chafed or broken, especially within the steering column. If the TSB fix fails and a new sensor doesn't work, the harness pigtail may need to be replaced as a next step.

Diagnosis Steps

1. Scan the EBCM for fault codes. Confirm C0710 is present, and note any other codes like C0455.
2. Access live data on a scan tool and observe the 'Steering Wheel Position' data, preferably in a graph format.
3. Start the engine and turn the wheel lock-to-lock. The reading should be smooth and consistent, typically between -500 and +500 degrees.
4. Watch for sudden dropouts, spikes, or 'noisy' signal patterns on the graph as you turn the wheel. This strongly indicates a connection issue.
5. If the data is erratic, locate the steering angle sensor on the steering column under the dash.
6. Disconnect the sensor's electrical connector. Inspect both the harness and sensor sides for signs of fretting corrosion (small dark smudges on the terminals).
7. Following TSB PI0639C, apply a piece of adhesive shim stock (Kent P40100) to the flat surface of the male connector to eliminate excessive play.
8. Using a clean nylon brush, apply a small amount of dielectric lubricant (GM 12377900) to the connector terminals. Do not over-apply.
9. Reconnect the connector firmly, clear the codes, and test drive the vehicle to see if the code returns.
10. If the code returns, test the sensor's power, ground, and signal wires for continuity and proper voltage.
11. If the wiring and connector are confirmed to be good, the steering angle sensor itself is likely faulty and should be replaced.
12. After replacement, perform the steering angle sensor calibration procedure with a compatible scan tool.
🎬 Watch: How to perform a steering angle sensor calibration.

Parts You'll Likely Need

• Dielectric Grease (OEM #12377900 (In Canada, 10953529)) — Required to protect the connector terminals from moisture and corrosion, as recommended by TSB PI0639C.
  Trusted brands: ACDelco, Permatex
  OEM price range: $10-$20
  Aftermarket price range: $5-$10
• Adhesive Back Shim Stock (OEM #P40100) — Used to tighten the fit of the electrical connector to prevent movement and fretting corrosion, as per the official GM TSB fix.
  Trusted brands: Kent Automotive
  OEM price range: $5-$15
  Aftermarket price range: $5-$15
• Steering Angle Sensor (OEM #26109034 or 13590209 (Verify with VIN)) — If the connector repair does not fix the issue, the sensor itself has likely failed. Part number can vary; VIN verification is critical. Some owners of similar platforms have had success using newer part numbers like 19418403 to replace older 6-pin sensors.
  Trusted brands: ACDelco, Dorman, Standard Motor Products
  OEM price range: $100-$150
  Aftermarket price range: $60-$100

Related Codes That Often Appear With This One

• C0455 — This code for 'Steering Position Sensor Circuit Malfunction' is often set alongside C0710, as they both relate to the same sensor circuit and are caused by the same connector issue described in TSB PI0639C.
• U2143 — This code indicates a 'Lost Communication With Steering Angle Sensor Module' and points to a more severe communication failure, often due to the same connector or wiring problems.

Technical Service Bulletins (TSBs) & Recalls

• PI0639C: Addresses a "Service StabiliTrak" message with DTC C0710 and/or C0455. It identifies the cause as fretting corrosion and looseness in the steering angle sensor connector and provides a specific repair procedure involving a shim and dielectric grease. It explicitly states not to replace the sensor first.
• SB-10043887-2153 (PI0639): An earlier version of the TSB which also details the fretting corrosion issue and the shim/grease repair for 2008-2012 models.

Platform-Specific Known Issues

• A widespread issue of fretting corrosion and looseness in the steering angle sensor connector is well-documented by GM in Technical Service Bulletin #PI0639C. This TSB is the definitive guide for this specific problem on Savana and Express vans.

Mechanic-Grade Diagnostic Values

• Steering Angle Sensor 5V Reference Circuit Voltage — expected: 4.8-5.2 V (measured between the 5V reference circuit pin and ground). Failure: Voltage outside this range suggests a fault in the EBCM or a short/open in the wiring.
• Steering Angle Sensor Low Reference Circuit Resistance — expected: Less than 2 Ω (measured between the harness connector and the EBCM connector). Failure: Resistance of 2 Ω or more indicates an open or high resistance in the ground circuit.
• Steering Angle Sensor Analog Signal Voltage (Centered) — expected: Approximately 2.5 V with the steering wheel centered.. Failure: Voltage significantly different from 2.5 V when wheels are straight ahead indicates a sensor or calibration issue.
• Steering Angle Sensor Analog Signal Voltage (Operating Range) — expected: Smoothly varies between approximately 0.4 V and 4.6 V when turning the wheel lock-to-lock.. Failure: Voltage that is stuck, jumps erratically, or goes outside this range indicates a faulty sensor or connection.
• Steering Angle Sensor Signal Circuit to Ground Resistance — expected: Infinite resistance (OL).. Failure: Any reading less than infinite indicates a short to ground in the signal wire.

Hidden / Shadow Codes Worth Checking

• C0710 5A: Plausibility Failure. This indicates the steering wheel angle reported by the sensor disagrees with the vehicle's actual turning rate as measured by other sensors (like yaw rate and wheel speed). (see via Professional scan tool like a GM Tech II or GDS2, under the EBCM data.)
• C0710 0F / C0710 17: Steering Position Signal Erratic / Shape/Waveform Failure. These point to an inconsistent or malformed signal, often caused by the fretting corrosion at the connector or an internal sensor failure. (see via Professional scan tool with GM-specific software.)
• C0710 42: Steering Wheel Angle Signal Calibration Not Programmed. This specifically indicates that the sensor's center position has not been learned by the EBCM. (see via Professional scan tool with GM-specific software.)

Scan Tool Commands That Help

• GM Tech2 / GDS2 / Professional Scan Tool: Steering Wheel Angle Sensor Learn / Calibration — This function is mandatory after replacing the steering angle sensor, replacing the EBCM, performing a wheel alignment, or if DTC C0710-42 is present. It resets the sensor's zero-degree center point.
• GM Tech2 / GDS2 / Professional Scan Tool: EBCM Live Data -> Steering Wheel Position — This is the primary diagnostic step. It allows a technician to view the angle, voltage, and phase signals in real-time to check for dropouts, noise, or implausible values while turning the steering wheel.

Wiring & Ground Locations

• EBCM (Electronic Brake Control Module) — On the left side frame rail, generally below the driver's door area.. This module receives the steering angle sensor data, sets code C0710, and controls the StabiliTrak system. All circuit tests ultimately lead back to its connector. It is also susceptible to water intrusion and corrosion, which can cause a host of issues.
• Steering Angle Sensor Connector — At the base of the steering column, under the driver's side dash, above the pedals.. This is the single most common failure point for this code due to fretting corrosion and looseness, as identified in TSB PI0639C.
• G300 / G302 — G300 is located on the body mount below the driver's door.. These are potential ground points for various modules. While not directly for the SAS, a poor ground in this area can introduce electrical noise and communication issues on the chassis.
• Serial Data Communication Enable Circuit 5986 — A light blue wire that runs from the Body Control Module (BCM) to the EBCM (Pin 19 on some models).. This is a 'wake-up' signal. If this circuit is open or has high resistance, the EBCM may not power on correctly, leading to a loss of communication and multiple codes, including U-codes that may accompany C0710.

Real Owner Repair Stories

• GM-Trucks.com Forum User (2012 Chevrolet Malibu (similar GM platform/era)) — Service ESC / Service Traction message with codes C0710 and U2143 (Lost communication with SAS).
  ❌ Tried (didn't work) Replaced the Steering Angle Sensor., Replaced the EBCM and programmed it with GM SPS2., Calibrated the new sensor and torque sensor.
  ✅ What actually fixed it The user discovered that live data for the steering angle was correct when viewed in the Power Steering Control Module (PSCM) but was frozen at 2.5V when viewed in the EBCM. This indicated the signal was not reaching the EBCM from the PSCM. The issue was traced to incorrect wiring diagrams (ALLDATA, Mitchell) for his specific late-production 2012 model. The problem was a break in the serial data line between the PSCM and the EBCM, which was not shown on the incorrect diagrams.