AutoCodes – GMC – B3655 GMC

B3655 GMC Code - Electrical Power Take Off Control Switch Circuit Low

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: B3655 GMC indicates Electrical Power Take Off Control Switch Circuit Low.
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 472

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 Mar 09, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3655 GMC 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 B3655 GMC - Electrical Power Take Off Control Switch Circuit Low - AutoCodes.com — B3655 GMC Code - Electrical Power Take Off Control Switch Circuit Low

What does this mean?

What are the Possible Causes of the DTC B3655 GMC?

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 B3655 GMC?

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 B3655 GMC 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 B3655 GMC Code

1. What are common symptoms of OBDII code B3655 GMC?

- Common symptoms include the power take off (PTO) not engaging or disengaging properly, illuminated warning lights on the dashboard, and possible loss of power to auxiliary equipment.

2. What can cause the OBDII code B3655 GMC to trigger?

- The code may be triggered by a malfunction in the electrical power take off (PTO) control switch circuit, such as a short circuit, open circuit, or wiring issues.

3. How can I diagnose the cause of OBDII code B3655 GMC?

- To diagnose the issue, you can perform a visual inspection of the PTO control switch and related wiring, check for loose connections, and use a multimeter to test for continuity and voltage.

4. What are some possible repair tips for fixing OBDII code B3655 GMC?

- Repair tips may include repairing or replacing damaged wiring, ensuring proper connections, resetting the fault codes, and testing the PTO control switch for proper functionality.

5. Can I still drive my vehicle with OBDII code B3655 GMC present?

- It is not recommended to drive the vehicle with the code present, as it may affect the operation of the power take off system and lead to further issues.

6. How serious is OBDII code B3655 GMC?

- While the code itself may not indicate a critical issue with the vehicle, it is important to address it promptly to avoid potential problems with the power take off system.

7. Is it possible to reset OBDII code B3655 GMC without repairs?

- Resetting the code without addressing the underlying issue may only provide a temporary solution, as the code is likely to reappear if the root cause is not fixed.

8. Can a DIY enthusiast repair OBDII code B3655 GMC?

- Depending on their skill level and access to tools, a DIY enthusiast may be able to diagnose and repair the issue related to the PTO control switch circuit, but professional help is recommended for complex electrical problems.

9. How much does it typically cost to repair OBDII code B3655 GMC?

- The cost of repairing the code can vary depending on the specific cause of the issue and whether professional assistance is required, but it may involve expenses for parts and labor.

10. Are there any preventive measures to avoid OBDII code B3655 GMC in the future?

- To prevent the code from reoccurring, you can perform regular inspections of the power take off system, ensure proper maintenance of electrical components, and address any issues promptly.