AutoCodes – Chevrolet – B3656 Chevrolet

B3656 Chevrolet Code - Electrical Power Take Off Control Switch Circuit High

Quick Answer

The Auxiliary Power Outlet (APO) Switch controls the operation of the Hybrid Control Module (HCM) APO state manager. Common causes include Faulty Auxiliary Power Outlet (APO) Switch, Auxiliary Power Outlet (APO) Switch harness is open or shorted, Auxiliary Power Outlet (APO) Switch 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: B3656 Chevrolet indicates Electrical Power Take Off Control Switch Circuit High.
Common causes: Common causes include Faulty Auxiliary Power Outlet (APO) Switch, Auxiliary Power Outlet (APO) Switch harness is open or shorted, Auxiliary Power Outlet (APO) Switch 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.

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Code Popularity 440

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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Table of contents Created and updated by William Orellana on Mar 09, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3656 Chevrolet Description

The Auxiliary Power Outlet (APO) Switch controls the operation of the Hybrid Control Module (HCM) APO state manager. The APO state manager commands one of three states from the Starter Generator Control Module (SGCM) (APO Off, APO Normal, APO Continuous). The APO switch is a momentary button, its output signal an input to an HCM analogue channel. Five volts are supplied to the switch and the returned voltage is measured relative to HCM signal ground to determine the switch state. A resistor network in the switch circuitry ensures that shorted high and low states can be diagnosed successfully. There are 2 valid voltage ranges of the return signal, one representing switch open, the other representing switch closed. If the voltage is lower than a threshold, a short low is indicated. Similarly, if the voltage is greater than the short high threshold, a short 'high' is indicated. The Diagnostic Trouble Code (DTC) sets if voltage is lower than a calibrated value, a short low is indicated or if the voltage is greater than a calibrated value the short high is indicated.

OBDII Code B3656 Chevrolet - Electrical Power Take Off Control Switch Circuit High - AutoCodes.com — B3656 Chevrolet Code - Electrical Power Take Off Control Switch Circuit High

What does this mean?

What are the Possible Causes of the DTC B3656 Chevrolet?

Faulty Auxiliary Power Outlet (APO) Switch
Auxiliary Power Outlet (APO) Switch harness is open or shorted
Auxiliary Power Outlet (APO) Switch circuit poor electrical connection
Faulty Hybrid Control Module (HCM)

How to Fix the DTC B3656 Chevrolet?

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 B3656 Chevrolet 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.

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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 B3656 Chevrolet Code

What does the OBDII code B3656 mean for a Chevrolet vehicle?

B3656 indicates a problem with the Electrical Power Take Off (PTO) Control Switch Circuit, specifically indicating a high voltage condition.

What are the common symptoms of the B3656 code?

Symptoms may include warning lights on the dashboard, malfunctioning PTO operation, and potential issues with vehicle performance.

What could cause the B3656 code to trigger?

Possible causes include a faulty PTO control switch, damaged wiring or connectors, or a malfunctioning control module.

How can I diagnose the B3656 code?

Use an OBDII scanner to confirm the code, then inspect the PTO control switch, wiring, and connectors for damage or corrosion.

What should I check first when troubleshooting the B3656 code?

Start by visually inspecting the PTO control switch and its wiring for any signs of wear, damage, or loose connections.

Can I clear the B3656 code after repairs?

Yes, you can clear the code using an OBDII scanner. Ensure that the underlying issue is resolved before doing so to prevent the code from returning.

Is it safe to drive with the B3656 code present?

While it may be safe for short distances, itâ€™s advisable to address the issue promptly to avoid further complications or damage to the vehicle.

What are the potential repair options for a B3656 code?

Repair options may include replacing the PTO control switch, repairing damaged wiring, or reprogramming the control module if necessary.

How much might it cost to fix the B3656 code?

Repair costs can vary widely depending on the specific issue, but it could range from $100 to $500 or more, depending on parts and labor.

Can a faulty battery cause the B3656 code?

Yes, low voltage or battery issues can affect the electrical system and potentially trigger the B3656 code, so itâ€™s worth checking the battery condition.