P1649 Code: EVAP Purge Solenoid Circuit Fault – What It Means & How to Fix It (iCarsoft CR MAX Guide)

If you drive a FCA Group vehicle (Chrysler, Jeep, Dodge, Ram) and your check engine light illuminates, a scan revealing code P1649 points to a critical issue in the evaporative emission (EVAP) system—specifically the purge solenoid control circuit. Unlike generic EVAP codes (e.g., P0440), P1649 is manufacturer-specific, defined as either “EVAP Purge Solenoid Control Circuit Open” or “Purge Solenoid Performance Fault” (varies by FCA model). Left unaddressed, it can cause failed emissions tests, reduced fuel efficiency, and rough idling—all while keeping your check engine light on.

Basic scanners may read P1649 but lack FCA-specific data to pinpoint the root cause (faulty solenoid, broken wiring, or ECM glitch). The iCarsoft CR MAX solves this: preloaded with FCA’s EVAP system specs, bi-directional solenoid testing, and advanced circuit diagnostics, it turns guesswork into precise repairs. This guide walks you through diagnosing and clearing P1649 step-by-step.

First: Understand P1649 – What It Is & Why It Matters

P1649 is not a universal code—clarity on its function and FCA-specific definitions is critical to effective repairs:

FCA-Specific P1649 Definitions

Key Symptoms of P1649

Common Causes of P1649

Why iCarsoft CR MAX Is Essential for P1649

P1649’s FCA-specific nature makes generic scanners ineffective. The CR MAX excels with features tailored to Chrysler, Jeep, Dodge, and Ram vehicles:

Step-by-Step: Diagnose P1649 with iCarsoft CR MAX

1. Connect CR MAX & Confirm P1649
   • Plug the CR MAX into your vehicle’s OBD-II port (under the dashboard) and power it on.
   • Select Vehicle Make > FCA Group (Chrysler/Jeep/Dodge/Ram), then your specific model/year. Use AutoVIN Recognition for accuracy (ensures FCA-specific code definitions).
   • Navigate to Engine > Fault Codes > Read Codes to confirm P1649. Note related EVAP codes (e.g., P0442 for small leaks, P0455 for large leaks)—these indicate additional issues.
   • Tap Code Details to view the exact FCA definition (e.g., “2020 Jeep Wrangler: Purge Solenoid Control Circuit Open”) and recommended first steps.
2. Check the EVAP Purge Fuse (Quick Fix First)
   • Go to Special Functions > Fuse Location > EVAP System on the CR MAX. The tool displays a fuse box diagram, highlighting the “EVAP Purge” fuse (e.g., 10A fuse in slot 23 for 2021 Ram 1500).
   • Locate and inspect the fuse: If blown (broken metal strip inside), replace it with a fuse of the same amperage.
   • Re-scan with the CR MAX: If P1649 clears, the fuse was the issue. If not, proceed to Step 3.
3. Analyze Real-Time EVAP Data
   • Navigate to Engine > Live Data > EVAP System and select these parameters:
     • “Purge Solenoid Duty Cycle” (ECM’s command to the solenoid)
     • “Purge Solenoid Circuit Voltage” (power sent to the solenoid)
     • “EVAP System Pressure” (stability indicates proper solenoid function)
   • Start the engine and warm it up (5–10 minutes, until operating temperature).
   • Observe data while the ECM cycles the solenoid (during idle/light acceleration):
     • Duty Cycle changes, but voltage stays 0V: No power to the solenoid (wiring/ECM issue).
     • Voltage present (~12V), but solenoid doesn’t activate: Faulty solenoid.
     • Voltage fluctuates randomly: Loose/corroded connector.
4. Test the Purge Solenoid with Bi-Directional Control
   • Navigate to Special Functions > EVAP Tests > Purge Solenoid Activation. Follow on-screen prompts (turn ignition to “On,” engine off, for safety).
   • Select Activate Solenoid (50% Duty Cycle):
     • Listen for a faint “click” (solenoid opening) and feel for vibration (if accessible).
     • Check live data: “Purge Solenoid Circuit Current” should read 0.5–1.5A (FCA normal range).
   • Interpret results:
     • No click/current: Solenoid is faulty (replace) or no power (check wiring).
     • Click/current present: Solenoid works—issue is in wiring/ECM.
5. Inspect Solenoid Wiring & Connectors
   • Step 1: Locate the purge solenoid via Component Location (typically mounted on the intake manifold or near the charcoal canister).
   • Step 2: Disconnect the solenoid’s 2-pin electrical connector.
   • Step 3: Test with CR MAX’s multimeter:
     • Voltage Test: Set to “DC Voltage.” Connect one probe to the connector’s “power” pin, the other to ground. Turn ignition “On”—should read ~12V. No voltage = broken wiring/fuse.
     • Resistance Test: Set to “Ohms.” Connect probes to the solenoid’s two pins. Normal range: 10–30 ohms. Infinite resistance = broken coil; <5 ohms = shorted coil (replace solenoid).
   • Step 4: Clean connectors with electrical contact cleaner—oxidation causes circuit resistance.

Repair & Verify: Clear P1649 for Good

Once you’ve identified the root cause, follow these steps to repair and confirm the fix:

1. Repair or Replace Components
   • Faulty Solenoid: Replace with an OEM FCA part (use CR MAX’s Part Lookup for the correct number, e.g., Mopar 68210576AA for Jeep Wrangler).
   • Broken Wiring: Repair small breaks with heat-shrink tubing; replace damaged harness sections for severe issues.
   • ECM Malfunction: Run ECM Health Check (via CR MAX) to confirm. Consult a FCA specialist for reprogramming/replacement.
2. Clear P1649 & Reset the EVAP System
   • Reconnect all components (solenoid, connectors, fuses).
   • Clear the code: Go to Fault Codes > Clear Codes and select P1649. Confirm deletion.
   • Run EVAP System Relearn (Special Functions > EVAP Tests > System Relearn)—resets the ECM’s EVAP adaptation data.
3. Verify Repairs
   • Idle the engine for 10 minutes—check for smooth operation (no rough idle).
   • Take a 30-mile test drive (mix of highway/city). Use CR MAX’s Data Logging to record EVAP parameters.
   • Re-scan after the drive: No P1649 + stable purge solenoid data = successful fix.

Prevent P1649 from Recurring

Use the CR MAX to keep your FCA’s EVAP system in top shape and avoid future P1649 codes:

Summary Table: P1649 Diagnosis Workflow (CR MAX-Powered)

Can I Drive with P1649?

Final Thoughts

P1649’s FCA-specific focus makes it a challenge for generic tools, but the iCarsoft CR MAX simplifies diagnosis and repair. By combining bi-directional solenoid testing, real-time EVAP data, and FCA-aligned circuit diagnostics, it helps you fix the root cause—whether a blown fuse, faulty solenoid, or broken wire—without wasting money on unnecessary parts.

For FCA vehicle owners and technicians, the CR MAX is the key to resolving P1649 quickly, passing emissions tests, and restoring fuel efficiency. Don’t let a stubborn check engine light slow you down—use the CR MAX to get your EVAP system back in top shape.