C1717 on 2003-2009 Hummer H2: Right Front Damper Actuator and Air Suspension Faults

What's Unique About the 2003-2009 Hummer H2

The Hummer H2 was built on a unique hybrid GM truck platform (GMT825 front, GMT820 rear) and featured an optional, complex rear air suspension system designed to provide self-leveling and adjustable ride height. This system, while advanced for its time, is a well-documented source of issues as the vehicles age. Unlike many vehicles where a suspension code might point to a simple sensor, on the H2, it often involves the entire network of air lines, compressors, solenoids, and control modules, which are prone to leaks, corrosion, and electrical failures. The front shocks, while not air-powered, contain electronic actuators for damping control that are tied into this same complex system.

Symptoms You May Notice

• "SERVICE AIR SUSPENSION" or "SERVICE SUSPENSION SYSTEM" message on the Driver Information Center (DIC)
• Rear of the vehicle may sag or sit unevenly, especially after being parked
• Air compressor may run continuously or not at all
• Noticeably harsher or bouncier ride quality, particularly from the front right
• Inability to raise or lower the rear of the vehicle using the ride height controls

Most Likely Causes

1. Damaged or Corroded Wiring Harness to RF Shock 🔴 High Probability The wiring for the shock actuators is routed along the frame and up into the shock tower, exposed to moisture, road salt, and debris. The 90-degree connector on top of the shock is a known failure point, where corrosion can build up or the pins can become loose, creating an open circuit.
   How to confirm: Visually inspect the wiring harness leading to the top of the right front shock tower. Disconnect the 90-degree electrical connector and inspect the pins for green or white corrosion. Check for continuity between the ESC module connector (pins for RF shock) and the shock actuator connector using a multimeter. A video by HummerFixes on YouTube shows a detailed diagnosis of a corroded pin at the main module connector causing a similar issue. 🎬 Watch: How to diagnose and fix corroded suspension module pins.
   Typical fix: Repair the broken or corroded section of the wire. Often, the connector pigtail itself needs to be replaced. In cases of corrosion, cleaning the pins with a contact cleaner may provide a temporary fix, but replacement is the long-term solution.
   Est. part cost: $15-$75 for a new pigtail connector and wiring supplies
2. Failed Right Front Shock Absorber Actuator/Solenoid 🟡 Medium Probability The electronic actuator is integrated into the shock absorber. Over time, the internal solenoid coil can fail due to heat, vibration, and age, creating an open circuit.
   How to confirm: After confirming the wiring is intact, test the resistance of the actuator itself at the shock's two electrical pins. A good actuator should have a resistance of approximately 2-3 ohms. An infinite resistance reading (OL on a multimeter) indicates an open circuit and a failed actuator.
   Typical fix: Replace the entire right front shock absorber assembly, as the actuator is not sold separately. It is highly recommended to replace shocks in pairs (left and right) for balanced performance. The ACDelco part is a common OEM replacement.
   Est. part cost: $350-$600 for a single genuine GM or ACDelco electronic shock
3. Faulty Air Suspension Control Module (ESC) ⚪ Low Probability → Shop Air Suspension Control Module The module is located under the vehicle, typically above the spare tire, and can suffer from water intrusion or corrosion at its main connector, leading to internal faults.
   How to confirm: This is typically a process of elimination. If the wiring and the shock actuator are confirmed to be good (correct resistance, no open/short in harness), the module is the likely culprit. A high-end scan tool (like a Tech 2) can communicate directly with the module to check its status and command outputs.
   Typical fix: Replace the air suspension control module. A used or remanufactured unit is often sourced as new parts can be difficult to find. The GM part number is often 89060585, which supersedes earlier numbers like 89038593.
   Est. part cost: $150-$400 for a used or remanufactured module

Diagnosis Steps

1. Verify the 'SERVICE AIR SUSPENSION' message is displayed on the DIC.
2. Scan the Electronic Suspension Control (ESC) module for codes using a compatible OBD-II scanner. Confirm C1717 is present.
3. Locate the right front shock absorber. Remove the plastic beauty cover from the shock tower 🎬 See this walkthrough for removing and replacing front shocks. if present.
4. Visually inspect the 90-degree electrical connector and the wiring harness leading to it for any obvious signs of damage, corrosion, or breaks.
5. Disconnect the harness from the shock. Check for green or white corrosion on the connector pins and inside the actuator port.
6. Using a multimeter set to Ohms, measure the resistance across the two pins on the shock absorber itself. A good actuator should read between 2-3 Ohms. An infinite reading (OL) indicates an open circuit and a failed shock actuator.
7. If the shock's resistance is within spec, inspect the wiring harness. Check for continuity from the shock connector back to the main Air Suspension Module connector. The module is located under the vehicle near the rear axle, often above the spare tire.
8. Inspect the large 16-pin connector (C451) at the Air Suspension Module for corrosion or backed-out pins, which is a known issue. Clean any corrosion found with contact cleaner.
9. If both the shock and wiring are confirmed to be good, the Air Suspension Module is the most likely cause of the fault. Confirm with a bi-directional scan tool if possible before replacing.

Parts You'll Likely Need

• Front Shock Absorber with Electronic Damping (OEM #ACDelco 580-1106 (replaces GM 84176631, 19300063)) — The internal solenoid/actuator fails, causing the open circuit. The entire shock must be replaced.
  Trusted brands: ACDelco, Arnott Industries
  OEM price range: $450-$600
  Aftermarket price range: $300-$500
• Air Suspension to Coil Spring Conversion Kit — Many owners choose to eliminate the problematic air suspension entirely. These kits replace the air springs and electronic shocks with passive coil springs and shocks, providing a more reliable long-term solution. 🎬 Watch: Upgrading to a more reliable passive shock system. This is a permanent fix for the system's chronic failures.
  Trusted brands: Strutmasters, Arnott Industries, Suncore
  OEM price range: N/A
  Aftermarket price range: $500-$1500 for a full kit
• Air Suspension Control Module (OEM #GM 89060585 (supersedes 89038593)) — Failure of the module's internal driver circuit for the RF shock can cause the C1717 code when the shock and wiring are known to be good.
  Trusted brands: GM Genuine, ACDelco, Dorman (remanufactured)
  OEM price range: $300-$500
  Aftermarket price range: $150-$400 (used/reman)

Related Codes That Often Appear With This One

• C0561 — This is a generic GM code for 'System Disabled Information Stored,' which often appears alongside more specific chassis fault codes like C1717.
• C1716 — This is the corresponding code for the Left Front Damper Actuator Open Circuit. If wiring is damaged in a common area, both codes could appear.

Technical Service Bulletins (TSBs) & Recalls

• A preliminary information bulletin, PI01103, addresses the service suspension message and notes that the 90-degree electrical connector at the top of the shock absorber may not be fully seated or may have internal contact issues. It advises inspecting the connector's green insulator and center post.

Platform-Specific Known Issues

• The air suspension system on the H2 is notoriously complex and prone to multiple failure points, including leaking rear air springs, failing compressors, and faulty height sensors. Many owners consider the system a 'money pit' and proactively convert to a standard coil spring suspension to avoid future issues.
• After converting to coil springs, the 'SERVICE AIR SUSPENSION' message will remain on. Owners on HummerForums.com report that this can be resolved by removing the air suspension relay located in the front driver's side fender well, which de-powers the control module.

Mechanic-Grade Diagnostic Values

• Front Shock Absorber Top Tennon Nut Torque — expected: 20 N.m (15 lb ft). Failure: N/A - This is an installation specification.
• Front Shock Absorber to Lower Control Arm Nut Torque — expected: 80 N.m (59 lb ft). Failure: N/A - This is an installation specification.
• Air Suspension Relay Coil Resistance — expected: Approximately 75 ohms. Failure: Significantly higher or infinite resistance (OL) indicates a failed relay coil.

Scan Tool Commands That Help

• GM Tech 2: Compressor Relay ON/OFF Command — Used to functionally test the air suspension compressor and its relay circuit, helping to isolate electrical issues from mechanical ones. This is typically used for diagnosing the air generation part of the system, not the C1717 damper code directly.
• GM Tech 2: Trim Height Learn / Calibration — After replacing suspension height sensors or the control module, this procedure is used to relearn the vehicle's proper ride height. It will not fix an open circuit code like C1717 but is often required after related system repairs.

Wiring & Ground Locations

• C451 — The main 16-pin connector for the Electronic Suspension Control (ESC) module, located under the vehicle near the rear axle/compressor assembly.. This is the primary connector for the suspension control module. It is highly susceptible to corrosion from water and road debris, which can cause open circuits for various components, including the front shock actuators.
• G402 — The main ground connection for the air suspension module, attached to the front of the air suspension mounting bracket under the rear of the vehicle.. A poor or corroded ground at this point can cause the entire suspension control module to malfunction or behave erratically, potentially leading to false codes or an inability to correctly read sensor data.
• G102 / G103 / G104 — Primary engine harness ground points. G102 is at the left front side of the engine block. G103 is at the top right rear of the engine. G104 is at the top left rear of the engine.. While not directly for the suspension module, poor engine-to-chassis grounds can introduce electrical noise and voltage offsets throughout the vehicle's electrical system. This can cause communication errors between modules (like the PCM and ESC) and lead to a wide range of difficult-to-diagnose electronic faults.

Real Owner Repair Stories

• CaddyInfo Cadillac Forum (1997 Cadillac Seville STS (Uses similar GM Class 2 electronics)) — Car would not start. Multiple codes were present, including RSS C1717 (RF Damper Actuator Open CKT) and U-series communication codes (U1255, U1016).
  ❌ Tried (didn't work) Trying a different set of keys., Applying WD-40 to the ignition cylinder., Extensive disassembly of the vehicle looking for the fault.
  ✅ What actually fixed it The PCM fuse was faulty. It passed a visual inspection but failed an electronic test (measured 0 amps instead of 30). Replacing the fuse resolved the no-start and cleared the communication and C1717 codes.
• HummerFixes on YouTube (2005 Hummer H2) — 'Service Air Suspension' message, multiple diagnostic trouble codes.
  ❌ Tried (didn't work) Initial assumption was a failed module.
  ✅ What actually fixed it A single wire had broken off its pin inside the main 16-way harness connector (C451) at the air suspension module due to corrosion. The fix involved extracting the pin, cleaning the wire, and soldering it back to a new or cleaned terminal pin.

OEM Part Supersession History

• 89038593 → 89060585 — Updated design or replacement for discontinued part.
  Heads up: These modules are for the 2003-2007 models. The 2008-2009 models use a different system and part numbers due to the switch to the GMLAN communication bus.

Model Year Variations Within This Range

• 2003-2007: These models use the GM Class 2 Serial Data bus for communication. Diagnostic tools like the Tech 2 do NOT require the CANDI (Controller Area Network Diagnostic Interface) module for diagnostics.
• 2008-2009: These models use the newer GMLAN (CAN bus) communication protocol. A Tech 2 scanner MUST be used with the CANDI module to communicate with the suspension system and other modules. The air compressor assembly and electronic shocks may also have different part numbers from earlier years.

Diagnostic Flowchart

Other Known Issues on This Vehicle

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

• HVAC Mode/Blend Door Actuator Failure 🟠 Medium — Very common across all model years, typically occurs after 80,000 miles. Results in incorrect air temperature or airflow direction.
• Cracked Cylinder Heads (2003-2005 6.0L) 🔴 High — A known issue with early Castech-brand cylinder heads, which can crack and cause coolant loss and engine overheating. Typically occurs between 90,000-150,000 miles.
• Failing Instrument Cluster Gauges 🟡 Low — Common on many GM trucks of this era. Stepper motors for gauges (speedometer, tachometer, etc.) fail, causing erratic or non-functional readings.
• Steering Wheel Position Sensor Failure 🟠 Medium — The sensor in the steering column can fail, causing the 'Service StabiliTrak' message and disabling the traction control system.
• Peeling/Flaking Interior Plastic Trim 🟡 Low — The gray painted plastic on interior components like the center console, door panels, and dash trim is notorious for peeling and flaking off over time.
• Heated Seat Element Failure 🟡 Low — The heating element in the driver's seat cushion frequently breaks, causing an open circuit and disabling the heated seat function for both front seats.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: For the Electronic Suspension Control (ESC) module, a used part from a reputable salvage yard is a very common and sensible repair. These modules are often reliable, and a used unit is significantly cheaper than a new-old-stock part, if one can even be found. Ensure the donor vehicle is from the correct model year range (2003-2007 or 2008-2009) to ensure compatibility.

Donor-vehicle mileage cap: roughly under 150000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• Inspect the main connector port (where C451 plugs in) on the used module for any signs of green or white corrosion, or bent pins.
• If possible, get a module from a vehicle in a dry, salt-free climate to minimize the chance of water intrusion damage.
• Check the part number on the used module to ensure it matches your original or the superseded number (89060585 for 2003-2007 models).

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

• While aftermarket shocks exist, many owners who wish to retain the electronic damping system prefer to stick with ACDelco (GM's OEM parts brand) for proper function and integration with the ESC module.

Aftermarket brands forum-validated for this vehicle:

• Arnott Industries: Widely respected for both OEM-style replacement electronic shocks and high-quality coil spring conversion kits.
• Strutmasters, Suncore: Well-known and commonly used brands specifically for coil spring conversion kits, which eliminate the problematic air and electronic systems entirely.

Brands owners have reported issues with on this vehicle:

• Unnamed, no-brand electronic shocks from online marketplaces. These often lack the correct internal valving or electronics, leading to persistent codes or poor ride quality.

Real Owner Stories

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

Related OBD-II Codes

• C0575 — Left Front Solenoid Circuit Malfunction; the companion code to C1717 for the opposite front shock actuator.
• C0580 — Right Rear Solenoid Circuit Malfunction; relates to the electronic actuator circuits within the rear shocks of the Autoride/ESC system.
• C0660 — Exhaust Solenoid Circuit; often occurs alongside shock codes when the Air Suspension Control Module (ESC) or its wiring harness (C451) suffers from corrosion.
• C0710 — Steering Position Sensor; another chassis code that can be triggered by communication issues or power faults within the electronic suspension and stability systems.

Frequently Asked Questions