C0594 – Right Rear Solenoid Circuit Open

System: Chassis | Standard: ISO/SAE Controlled | Fault type: Circuit/Open

Official meaning: Right Rear Solenoid Circuit Open

Definition source: SAE J2012 naming/structure guidance

What Does C0594 Mean?

C0594 – Right Rear Solenoid Circuit Open is an ISO/SAE controlled chassis diagnostic trouble code that indicates the control module has detected an open circuit condition in the right rear solenoid electrical circuit. “Circuit open” means the module cannot see the expected electrical continuity or load in that circuit when it performs monitoring or when the solenoid is commanded.

This code describes an electrical problem in the circuit (wiring, connectors, terminals, power/ground, or the solenoid coil) rather than confirming a specific component has failed. The authoritative meaning remains: Right Rear Solenoid Circuit Open.

Quick Reference

• Code: C0594
• Official Title: C0594 – Right Rear Solenoid Circuit Open
• Official Meaning: Right Rear Solenoid Circuit Open
• System: Chassis
• Standard classification: ISO/SAE Controlled
• Fault type: Circuit/Open
• What it indicates: The module cannot detect proper electrical continuity/load in the right rear solenoid circuit
• What to prioritize: Connector/terminal condition, harness continuity, and verified power/ground under load

Symptoms

Symptoms depend on what chassis function uses the right rear solenoid, but an open circuit can cause the module to limit or disable related operation and request warning indicators.

• Warning indicators illuminated: A chassis-related warning lamp and/or stability/traction/ABS-related indicators may turn on, depending on the vehicle’s integration.
• Reduced or disabled function: The system that relies on the right rear solenoid may be limited or placed into a fail-safe strategy.
• Handling or control changes: Changes may be noticed during braking, cornering, or when vehicle dynamics systems would normally intervene.
• Ride or response changes: If the solenoid is part of a chassis actuator strategy, ride response may feel different.
• Intermittent behavior: A loose terminal or damaged conductor can open/close with vibration or suspension movement, causing the issue to appear and disappear.
• Additional DTCs: Other chassis codes may store if the module detects related electrical or functional issues.

Common Causes

C0594 is set when the right rear solenoid circuit is electrically open. Typical root causes are circuit integrity problems rather than a calibration or performance issue.

• Open in the harness: Broken wire, stretched conductor, or internal break that interrupts continuity to the right rear solenoid.
• Connector or terminal fault: Corrosion, moisture intrusion, backed-out terminals, poor pin fit, damaged locks, or overheated terminals preventing current flow.
• Solenoid coil open: Internal winding open (no continuity) or an intermittent open within the solenoid assembly.
• Power supply open: Loss of the circuit’s power feed due to an open in the supply path (for example, an open at a fuse/relay feed point or upstream connector).
• Ground/control side open: Open ground path, open control wire, or high resistance that effectively behaves as an open under load.
• Module connector/circuit issue: Poor terminal contact at the control module connector or an internal driver issue (consider only after external circuit checks prove good).

Diagnosis Steps

Use a scan tool that can access chassis DTCs, a digital multimeter, and the correct wiring diagram for the exact vehicle configuration. For circuit/open faults, verifying continuity and voltage drop under load is more reliable than checking voltage with no load.

1. Confirm the code and capture data: Read all stored/active DTCs. Record freeze-frame/failure records if available and note whether C0594 is current or history.
2. Check for related electrical codes: If multiple solenoid or supply-related codes are present, diagnose shared power/ground paths first before focusing on a single corner circuit.
3. Identify the right rear solenoid circuit: Using service information, confirm the location, connector identification, pinout, and which module pins control and/or supply the right rear solenoid.
4. Perform a visual inspection: Inspect the right rear harness routing and connector area for rubbing, pinching, exposed wiring, prior repair damage, or signs of moisture intrusion.
5. Inspect connectors and terminals closely: With the key off, disconnect the solenoid connector. Look for corrosion, bent pins, pushed-back terminals, poor pin tension, or melted plastic. Correct terminal fit issues before deeper testing.
6. Check solenoid coil continuity: Measure resistance across the solenoid terminals per service specifications. An open/infinite reading supports an internal open. If readings change while gently moving the connector or solenoid, suspect an intermittent open at the terminal or inside the coil.
7. Verify power and ground/control integrity under load: With the circuit connected (back-probed where appropriate), verify the presence of the correct supply and a solid ground/control path. Use a test light or voltage-drop method to identify high resistance that may mimic an open.
8. Continuity test the harness end-to-end: With connectors unplugged as required and the circuit powered down, test continuity from the solenoid connector back to the module (and through any intermediate connectors). Check each conductor for opens and verify there is no unintended continuity to power or ground.
9. Use bidirectional control if supported: Command the right rear solenoid on/off and measure voltage at the solenoid connector. Compare the commanded state to the electrical response to determine whether the issue is in the solenoid, wiring/connector, or module side.
10. Inspect the module connector if needed: If the solenoid and wiring test correctly, inspect the control module connector terminals for corrosion, poor pin tension, or water tracks that could open the circuit electrically.
11. Clear codes and verify the repair: After repairs, clear DTCs and perform a functional test/road test that exercises the chassis system. Re-scan to confirm C0594 does not return as pending or confirmed.

Possible Fixes

Repairs must match the confirmed cause of the open circuit. Do not replace parts until testing shows the failure point.

• Repair or replace damaged wiring: Fix open conductors, chafed sections, or damaged splices in the right rear solenoid circuit and secure routing to prevent repeat damage.
• Restore connector/terminal integrity: Clean corrosion, dry moisture intrusion, replace damaged terminals, correct pin tension, and ensure connectors are fully seated and locked.
• Replace the right rear solenoid: If resistance/continuity tests confirm the solenoid coil is open (or repeatably intermittent open), replace the solenoid as appropriate for the system design.
• Restore circuit power supply: Repair the open in the supply path and correct any upstream connection issues identified during testing.
• Restore ground/control path: Repair open grounds/control wires and correct excessive voltage drop on the return path.
• Address module-side issues only after proving the circuit: If all external circuit checks pass and the fault persists, repair terminal issues at the module connector or follow service procedures for module diagnostics and any required configuration steps.

Can I Still Drive With C0594?

In many cases the vehicle may remain drivable, but C0594 is a chassis electrical fault and can cause the associated chassis function to be limited or disabled because the module cannot control the right rear solenoid reliably. If warning indicators are on or the vehicle’s handling/braking behavior feels different, driving risk increases—especially during hard braking, abrupt maneuvers, or low-traction conditions.

If you must drive, do so cautiously and prioritize diagnosis and repair. Do not ignore the code if it returns after clearing, or if multiple chassis-related warnings are present.

Repair Costs

Repair cost depends on whether the confirmed root cause is wiring, connector condition, a switch or module issue, or the labor needed to diagnose the fault correctly.

Last updated: March 27, 2026