AutoCodes – Generic – P1645

P1645 Code - Evaporative Emission Purge Solenoid Output Circuit

Quick Answer

The Powertrain Control Module (PCM) contains Output Driver Modules (ODM) that provides 7 switchable ground outputs for operating solenoids, relays, indicator lights, and other devices. Common causes include Faulty Evaporative Emission Vent Solenoid, Evaporative Emission Vent Solenoid harness is open or shorted, Evaporative Emission Vent Solenoid circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1645 indicates Evaporative Emission Purge Solenoid Output Circuit.
Common causes: Common causes include Faulty Evaporative Emission Vent Solenoid, Evaporative Emission Vent Solenoid harness is open or shorted, Evaporative Emission Vent Solenoid circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 21,236

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Feb 24, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P1645 Description

The Powertrain Control Module (PCM) contains Output Driver Modules (ODM) that provides 7 switchable ground outputs for operating solenoids, relays, indicator lights, and other devices. Each of these ground outputs has fault lines that feedback to the PCM microprocessor. When the output is off, the output driver should receive the 12 volts fed to the solenoid, relay, etc. When the output is on, it should receive zero volts, since it is grounding the output. If PCM sees zero volts when the output is off or 12 volts when the output is on, it sets a fault line low. The Diagnostic Trouble Code (DTC) is used to monitor the fault line of the EVAP control solenoid. With the engine runtime over 10 seconds, the PCM detects that the EVAP Solenoid Circuit line was low, conditions met for 2 seconds, and the DTC sets.

OBDII Code P1645 - Evaporative Emission Purge Solenoid Output Circuit - AutoCodes.com — P1645 Code - Evaporative Emission Purge Solenoid Output Circuit

What does this mean?

What are the Possible Causes of the DTC P1645?

Faulty Evaporative Emission Vent Solenoid
Evaporative Emission Vent Solenoid harness is open or shorted
Evaporative Emission Vent Solenoid circuit poor electrical connection

How to Fix the DTC P1645?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1645 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1645 code?

Need more information on how to fix the P1645 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1645 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1645 Audi — CAN Data Bus 4WD No Signal
P1645 Buick — Evaporative Emission Purge Solenoid Output Circuit
P1645 Cadillac — Evaporative Emission Purge Solenoid Output Circuit
P1645 Chevrolet — Evaporative Emission Purge Solenoid Output Circuit
P1645 GMC — Evaporative Emission Purge Solenoid Output Circuit
P1645 Honda — MOTFSB Signal Malfunction
P1645 Hyundai — Booster Voltage Operate Injector
P1645 Lexus — Body Control Module Malfunction
P1645 Oldsmobile — Evaporative Emission Purge Solenoid Output Circuit
P1645 Toyota — Body Control Module Malfunction
P1645 Volkswagen — CAN Data Bus 4WD No Signal

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P1645 Code

1. What are the common symptoms of OBDII code P1645 (Evaporative Emission Purge Solenoid Output Circuit)?

The common symptoms include rough idling, decreased fuel efficiency, and the illumination of the Check Engine Light.

2. What are the possible causes of OBDII code P1645?

Possible causes include a faulty evaporative emission purge solenoid, damaged wiring or connectors in the purge solenoid circuit, or a malfunctioning engine control module (ECM).

3. How can I diagnose the cause of OBDII code P1645?

Diagnosis typically involves using an OBDII scanner to retrieve the trouble codes, inspecting the wiring and connectors for any damage, and testing the evaporative emission purge solenoid for proper functionality.

4. Can I drive my vehicle with OBDII code P1645?

It is not recommended to drive your vehicle with this code as it can lead to further engine and emission system issues. It's best to address the problem promptly.

5. How do I repair OBDII code P1645?

Repairing this code may involve replacing the faulty evaporative emission purge solenoid, repairing any damaged wiring or connectors, or reprogramming the engine control module if necessary.

6. Are there any DIY tips for fixing OBDII code P1645?

While basic inspections and connector checks can be done by DIY enthusiasts, it's recommended to have a professional mechanic diagnose and repair the issue to ensure proper resolution.

7. What is the function of the evaporative emission purge solenoid in the vehicle's emission system?

The evaporative emission purge solenoid is responsible for controlling the flow of fuel vapors from the charcoal canister to the engine for combustion, reducing emissions.

8. How important is it to address OBDII code P1645 promptly?

It is crucial to address this code promptly as it can affect the vehicle's performance, fuel efficiency, and emissions, potentially leading to more severe issues if left unresolved.

9. Can a faulty gas cap trigger OBDII code P1645?

While a faulty gas cap can trigger evaporative emission system codes, OBDII code P1645 specifically relates to the purge solenoid output circuit and may not be directly caused by a faulty gas cap.

10. Is it necessary to reset the Check Engine Light after repairing OBDII code P1645?

After repairing the issue causing OBDII code P1645, it's advisable to clear the trouble codes and reset the Check Engine Light using an OBDII scanner to ensure the system recognizes the problem has been resolved.