C0455 on 2007-2011 Chevrolet Silverado: Steering Angle Sensor Circuit Fault Guide

What's Unique About the 2007-2011 Chevrolet SILVERADO

The GMT900 platform, which includes the 2007-2011 Silverado, is known for a specific design issue that triggers code C0455. 🎬 Watch: Diagnosing C0455 and Service Stabilitrak warnings The electrical connector for the steering angle sensor is prone to fretting corrosion and can develop excessive play, leading to an intermittent or poor signal. Fretting corrosion appears as small dark smudges on the electrical terminals. General Motors issued a Technical Service Bulletin (PI0639C, later superseded by PI0639D) that explicitly advises against replacing the sensor initially, instead recommending a specific procedure to secure the connector and improve its conductivity.

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)
• "Service Traction Control" message on the DIC
• StabiliTrak/Traction Control indicator light illuminated
• Cruise control may not function.
• In rare cases, ABS may engage unexpectedly or cause a dragging or locking sensation, particularly during turns.

Most Likely Causes

1. Poor Connection at Steering Angle Sensor Connector 🔴 High Probability → Shop Steering Angle Sensor A known issue on the GMT900 platform where the connector develops excessive clearance and fretting corrosion, interrupting the signal. TSB PI0639D directly addresses this.
   How to confirm: Visually inspect the sensor's 8-pin electrical connector terminals (located at the base of the steering column) for dark smudges or corrosion. With a scan tool monitoring live data, wiggle the connector to see if the steering angle value drops out or becomes erratic.
   Typical fix: Perform the procedure in TSB #PI0639D: Disconnect the connector. Clean the male and female terminals with a dedicated nylon brush. Apply a small amount of dielectric grease (GM P/N 12377900). Add an adhesive shim (Kent Automotive P/N P40100, which is 5/8" x 1/8" adhesive-backed rubber) to the flat surface of the male connector body to eliminate play. Reconnect and clear codes.
   Est. part cost: $10-$25
2. Failed Steering Angle Sensor 🟡 Medium Probability → Shop Steering Angle Sensor The sensor can fail internally, but this is far less common than the connector issue. It should only be suspected after the TSB for the connector has been performed without success.
   How to confirm: After confirming the connector and wiring are good, use a scan tool to monitor the steering angle sensor's live data. If the data is erratic, does not change when the wheel is turned, or is stuck at a fixed value, the sensor has likely failed.
   Typical fix: Replace the steering angle sensor. This requires removing lower dash panels and potentially lowering the steering column for access. A steering angle sensor calibration must be performed with a scan tool after replacement. The new sensor comes with a locking pin to keep it centered; do not remove this pin until the sensor is fully installed.
   Est. part cost: $60-$180
3. Improper Steering Wheel Installation/Alignment ⚪ Low Probability If the steering wheel was removed for a prior repair (like a clock spring or intermediate shaft replacement) and not re-centered correctly, it can cause this code.
   How to confirm: Drive on a straight, level road. If the steering wheel is not centered, this is a likely cause. TSB #PIT4225F notes this can occur if the steering wheel is not properly installed on the shaft by aligning the marks.
   Typical fix: The vehicle needs a proper four-wheel alignment, and then the steering angle sensor must be reset/calibrated using a compatible scan tool.

Rare But Worth Checking

• Damaged Wiring Harness: The wiring between the Steering Angle Sensor and the EBCM can become chafed or damaged, though this is uncommon. If the TSB fix fails and a new sensor doesn't solve the issue, TSB PI0639C suggests replacing the harness-side connector pigtail. A visual inspection and continuity check are needed.
• Faulty Electronic Brake Control Module (EBCM): In very rare instances, the EBCM itself can be the source of the problem. This should only be considered after all other possibilities, including wiring and grounds, have been thoroughly exhausted.

Diagnosis Steps

1. Read all fault codes from the Electronic Brake Control Module (EBCM) with a scanner capable of reading 'C' (Chassis) codes. Note if C0710 is also present.
2. Access the steering angle sensor at the base of the steering column, under the driver's side dashboard. You will likely need to remove the lower dash panel and an air duct.
3. Disconnect the sensor's electrical connector. Inspect the male and female terminals for dark smudges (fretting corrosion) or damage. A magnifying glass may be helpful.
4. Check for excessive up-and-down play in the connector housing. If loose, this is the primary suspect.
5. Perform the fix outlined in TSB #PI0639D: Clean terminals with a nylon brush, apply dielectric grease (GM P/N 12377900), and add an adhesive shim (Kent Automotive P/N P40100) to the male connector to eliminate play.
6. If the connector appears clean and tight, use a scan tool to monitor the live data for the 'Steering Wheel Angle'.
7. Turn the steering wheel lock-to-lock. The angle reading should change smoothly and correspond to the wheel's position. If it's erratic, frozen, or doesn't change, the sensor is the primary suspect.
8. Verify the steering wheel is centered when driving straight. If it's off, an alignment and sensor calibration are needed.
9. If the sensor and alignment are good, inspect the wiring harness between the sensor and the EBCM for any signs of damage, chafing, or corrosion. If the DTC resets after the TSB fix, the next step recommended by GM is to replace the harness-side connector pigtail.
10. If all other steps fail, the final step would be to suspect a faulty EBCM, though this is highly unlikely.

Parts You'll Likely Need

• Steering Angle Sensor (OEM #19418403, 25833069) — This is the part to replace if the connector fix fails and the sensor is confirmed to be faulty via scan tool data.
  Trusted brands: ACDelco, Dorman
  OEM price range: $90-$180
  Aftermarket price range: $60-$120
• Dielectric Lubricant (OEM #12377900 (GM), 10953529 (in Canada)) — Required for the TSB procedure to prevent future corrosion on the connector terminals.
  Trusted brands: Permatex, ACDelco
  OEM price range: $10-$20
  Aftermarket price range: $5-$10
• Adhesive Back Shim Stock (OEM #P40100 (Kent Automotive)) — A small piece of 5/8" x 1/8" adhesive-backed rubber shim is used in the TSB procedure to tighten the sensor connector and prevent movement.
  Trusted brands: Kent Automotive
  OEM price range: $5-$10
  Aftermarket price range: $5-$10

Related Codes That Often Appear With This One

• C0710 — This code is also for the steering angle sensor circuit. TSBs #PIT4225F and #PI0639D mention that C0455 and C0710 are often set together for the same underlying causes, specifically the fretting corrosion at the connector.

Technical Service Bulletins (TSBs) & Recalls

• PI0639D: 'Service Stabilitrak message displayed in DIC and DTC C0455 or C0710' - This TSB details the primary cause of a loose/corroded connector and the procedure to fix it with a shim and dielectric grease. It covers a wide range of GMT900 trucks and SUVs.
• PIT4225F: 'Service Brakes, Electric' - This TSB notes that C0455 can be set if the steering wheel is not properly installed on the steering shaft after a repair, requiring re-centering and calibration.

Platform-Specific Known Issues

• A GM Technical Service Bulletin (PI0639D, which supersedes PI0639C) specifically addresses C0455 and C0710 on this platform, pointing to fretting corrosion and looseness in the steering angle sensor connector as the primary cause.
• The TSB explicitly states 'DO NOT replace the steering position sensor for this condition' as the initial step, highlighting how common the connector issue is.

Mechanic-Grade Diagnostic Values

• 5V Reference Circuit Voltage — expected: 4.8-5.2V between the 5V reference circuit terminal (Pin 1) and a known good ground.. Failure: Voltage below 4.8V or above 5.2V points to a short or open in the wiring, or a faulty EBCM.
• Low Reference Circuit Resistance — expected: Less than 20 ohms between the low reference circuit terminal (Pin 2) and a known good ground.. Failure: Resistance greater than 20 ohms indicates a poor ground connection for the sensor.
• Analog Signal Voltage (Scan Tool) — expected: Approximately 2.5V with the steering wheel centered. Ranges from ~0.25V (full left turn) to ~4.75V (full right turn).. Failure: Voltage is stuck, erratic, or does not correspond to steering wheel movement.

Scan Tool Commands That Help

• Tech2 / GDS2 / Professional Scan Tool: Steering Angle Sensor Calibration / Learn — This procedure is mandatory after replacing the steering angle sensor or after any service that involves disconnecting the steering column or altering the vehicle's alignment. It zeros the sensor's position relative to the straight-ahead position of the wheels.
• Professional Scan Tool (e.g., Autel): Steering Angle Sensor Reset — This function clears the old calibration values stored in the EBCM before performing the 'Learn' procedure. Failing to reset first can sometimes cause the new calibration to fail.

Wiring & Ground Locations

• B99 Steering Angle Sensor Connector — At the base of the steering column, under the driver's side dashboard.. This is the primary point of failure due to fretting corrosion and looseness, as identified in TSB PI0639D. All circuit tests for the sensor begin at this connector.
• EBCM Ground — On the frame rail under the driver's door area.. A poor ground connection for the Electronic Brake Control Module (EBCM) can cause a variety of communication and sensor-related fault codes, including C0455. Cleaning this ground is a key diagnostic step if circuit tests are inconclusive.
• K17 Electronic Brake Control Module (EBCM) — Mounted on the driver's side frame rail, below the driver's door.. This module powers the sensor, receives its signals, and sets the C0455 fault code. The wiring harness between the B99 connector and the K17 module can be tested for continuity if the sensor and its connector are known to be good.

Real Owner Repair Stories

• GMTNation Forum (GMT900 Platform Truck (year not specified)) — "Service Stabilitrac" light and C0455 code.
  ❌ Tried (didn't work) Replacing the steering angle sensor with a Dorman part., Replacing the steering angle sensor again with an OEM part.
  ✅ What actually fixed it The user concluded the issue was not the sensor itself, but likely an error in the installation process, such as failing to properly center the steering wheel before installing the new sensor, which prevented successful calibration. The code returned immediately after both replacements, highlighting the importance of correct installation procedure.
• Tahoe Yukon Forum (GMT900 Yukon (year not specified)) — "Service Stability" message and C0455 code appeared immediately after replacing the intermediate steering shaft.
  ❌ Tried (didn't work) A dealer quoted $542 to replace the sensor, claiming it could not be reset.
  ✅ What actually fixed it The community determined the steering wheel was likely reinstalled 360 degrees out of alignment during the shaft repair. The correct fix was to have an alignment shop properly center the steering wheel and then perform a sensor recalibration with a scan tool.

OEM Part Supersession History

• 15112675 → 25833069 — Standard part evolution/update.
• 25833069 → 15886733 — Standard part evolution/update.
  Heads up: Part number 15886733 is now widely discontinued. The recommended replacement is to use the earlier 25833069, which is functionally interchangeable. Both are 8-pin connectors.

Model Year Variations Within This Range

• 2007-2008 (early models): Some very early 2007-2008 models were equipped with a 6-pin steering angle sensor that was discontinued. The replacement part is an 8-pin sensor (like PN 25833069), and some owners report that a new harness connector pigtail is required for the conversion, while others state the original 6-pin connector plugs in and leaves two pins unused. This can be a point of confusion during diagnosis and repair.