Understanding DTC Codes P0600-P0699 Control Module and Output Control Malfunctions

Understanding DTC Codes P0600-P0699 Control Module and Output Control Malfunctions

​When it comes to diagnosing and repairing automotive issues, understanding Diagnostic Trouble Codes (DTCs) is crucial. In this article, we will explore the DTC codes P0600-P0699, which specifically deal with control module and output control malfunctions. Whether you are a professional mechanic or a car enthusiast, Electronic Repair Company's auto-tuning blog provides comprehensive insights to help you address these problems effectively.

P0600 – Serial Communication Link Malfunction:
The P0600 code indicates a malfunction in the serial communication link between the control module and other components. This issue often arises due to loose connections, damaged wiring, or faulty control modules. Our blog will guide you on how to identify and resolve this communication error swiftly.

P0601 – Control Module Read Only Memory (ROM):
A P0601 code points to an issue with the control module's read-only memory. This error can occur due to corrupted data or a faulty control module. By visiting our auto-tuning blog, you will discover detailed instructions on troubleshooting and repairing this specific problem.

P0602 – Control Module Not Programmed:
When the control module in your vehicle is not programmed correctly or is missing vital programming information, the P0602 code is triggered. Our blog will provide you with step-by-step instructions on how to program or reprogram the control module, ensuring seamless operation of your vehicle.

P0603 – Control Module Long Term Memory Reset:
The P0603 code signifies that the control module's long-term memory has been reset. This issue can result in drivability problems and loss of certain vehicle settings. Electronic Repair Company's blog will assist you in understanding the causes behind this code and guide you in resolving it effectively.

P0604 – Control Module Random Access Memory (RAM):
A malfunction in the control module's random access memory can trigger the P0604 code. This issue can lead to performance issues and erratic behavior of various vehicle systems. By following our blog, you will gain insights into diagnosing and rectifying this RAM-related problem.

P0605 – Control Module Programming Read Only Memory (ROM):
The P0605 code indicates an issue with the control module's programming read-only memory. This can occur due to corrupted or missing data within the ROM. Our auto-tuning blog will provide you with expert advice on resolving this specific problem swiftly and efficiently.

P0606 – Control Module Internal Performance:
When the control module's internal performance is compromised, the P0606 code is triggered. This issue can be caused by various factors, including software glitches, electrical faults, or mechanical failures within the control module. By following our blog, you will gain valuable insights on diagnosing and rectifying this performance-related issue.

P0607 – ECU Malfunction:
The P0607 code indicates a malfunction in the Engine Control Unit (ECU). This issue can lead to drivability problems, poor fuel efficiency, or even engine stalling. Our blog will guide you through the necessary steps to identify the cause of this malfunction and provide effective solutions.

P0608 – Control Module VSS Output “A” Malfunction:
A malfunction in the control module's Vehicle Speed Sensor (VSS) output circuit can trigger the P0608 code. This can result in incorrect speedometer readings, erratic shifting, or cruise control issues. Our comprehensive blog post will provide

P0609 – Control Module VSS Output “B” Malfunction:
Similar to the previous code, the P0609 code points to a malfunction in the control module's VSS output circuit, but specifically related to output "B." Our auto-tuning blog will delve into the intricacies of this issue, helping you diagnose and rectify it promptly.

P0610 – Control Module Vehicle Options Incorrect:
When the control module detects incorrect vehicle options or configurations, it triggers the P0610 code. This issue can affect various aspects of your vehicle's functionality, such as lighting, security systems, or comfort features. Our blog post will guide you through the process of correcting the vehicle options to resolve this code effectively.

P0615 – Starter Relay Control Circuit:
The P0615 code signifies a problem with the starter relay control circuit. This issue can result in difficulties starting your vehicle or intermittent starting problems. Our comprehensive guide will assist you in diagnosing and repairing the starter relay control circuit to restore proper functionality.

P0616 – Starter Relay Control Circuit Low Voltage:
If the voltage in the starter relay control circuit falls below the expected range, the P0616 code is triggered. This issue can lead to weak or no cranking of the engine. By following our blog's instructions, you will learn how to identify the low voltage source and rectify it effectively.

P0617 – Starter Relay Control Circuit High Voltage:
In contrast to the previous code, the P0617 code indicates a high voltage condition in the starter relay control circuit. This issue can cause excessive current flow, potentially damaging the starter motor or other electrical components. Our blog will guide you on diagnosing and resolving this high voltage issue for optimal performance.

P0620 – Generator Control Circuit Malfunction:
The P0620 code suggests a malfunction in the generator control circuit, also known as the alternator. This issue can result in a discharged battery, electrical system malfunctions, or even engine stalling. Our auto-tuning blog will provide you with in-depth insights and troubleshooting steps to address this generator control circuit malfunction effectively.

P0621 – Generator L-Terminal Circuit:
When the L-terminal circuit of the generator malfunctions, the P0621 code is triggered. This issue can lead to charging system problems and a drained battery. By following our blog, you will gain a comprehensive understanding of the generator L-terminal circuit and learn how to diagnose and repair it efficiently.

P0622 – Generator F-Terminal Circuit:
Similar to the previous code, the P0622 code relates to the generator circuit, but specifically focuses on the F-terminal. A malfunction in this circuit can cause charging system issues and battery drain. Our blog post will equip you with the necessary knowledge to diagnose and rectify the generator F-terminal circuit problem accurately.

P0625 – Generator F-Terminal Circuit Low Voltage:
The P0625 code indicates low voltage in the generator's F-terminal circuit. This issue can result in inadequate charging of the battery, leading to power-related problems. Our auto-tuning blog will guide you through the necessary steps to identify and resolve the low voltage condition in the F-terminal circuit efficiently.

P0626 – Generator F-Terminal Circuit High Voltage:
In contrast to the previous code, the P0626 code signifies a high voltage condition in the generator's F-terminal circuit. This issue can cause excessive charging, potentially damaging the battery or other electrical components. Our blog will provide you with detailed instructions on diagnosing and rectifying this high voltage issue for optimal performance.

P0628 – Fuel Pump Relay Control Circuit Low Voltage:
When the voltage in the fuel pump relay control circuit drops below the expected range, the P0628 code is triggered. This issue can result in fuel delivery problems, leading to engine performance issues or stalling. Our comprehensive blog post will guide you through the process of identifying the low voltage source and resolving the fuel pump relay control circuit problem effectively.

P0629 – Fuel Pump Relay Control Circuit High Voltage:
Contrary to the previous code, the P0629 code indicates a high voltage condition in the fuel pump relay control circuit. This issue can cause excessive current flow, potentially damaging the fuel pump or other electrical components. Our blog will provide you with expert guidance on diagnosing and resolving this high voltage issue, ensuring proper fuel delivery and system functionality.

P0638 – Throttle Actuator Control (TAC) Command Performance:
The P0638 code relates to a performance issue in the throttle actuator control system. This issue can lead to reduced engine power, erratic throttle response, or even engine stalling. By following our blog's detailed instructions, you will gain insights into diagnosing the TAC command performance problem and effectively resolving it.

P0641 – PCM Voltage Out of Tolerance Condition on the 5-volt Reference Circuit:
The P0641 code indicates that the voltage on the Powertrain Control Module's (PCM) 5-volt reference circuit is outside the acceptable range. This issue can cause various sensor-related problems and improper engine operation. Our auto-tuning blog will provide you with step-by-step instructions to diagnose and rectify this voltage out-of-tolerance condition for optimal PCM performance.

P0645 – Air Conditioning (A/C) Clutch Relay Control Circuit:
When there is a malfunction in the control circuit of the A/C clutch relay, the P0645 code is triggered. This issue can result in improper A/C compressor engagement, leading to inadequate cooling or no cooling at all. Our blog post will guide you through the process of diagnosing and repairing the A/C clutch relay control circuit to restore proper A/C functionality.

P0646 – Air Conditioning (A/C) Clutch Relay Control Circuit Low Voltage:
The P0646 code indicates low voltage in the control circuit of the A/C clutch relay. This issue can result in insufficient power supply to the A/C clutch, leading to inadequate cooling performance. By following our blog's instructions, you will learn how to identify the low voltage source and rectify it effectively for optimal A/C operation.

P0647 – Air Conditioning (A/C) Clutch Relay Control Circuit High Voltage:
In contrast to the previous code, the P0647 code suggests a high voltage condition in the control circuit of the A/C clutch relay. This issue can cause excessive current flow, potentially damaging the A/C clutch or other electrical components. Our blog will guide you on diagnosing and resolving this high voltage issue, ensuring proper A/C functionality and preventing further damage.

P0650 – Malfunction Indicator Lamp (MIL) Control Circuit:
The P0650 code relates to a malfunction in the control circuit of the Malfunction Indicator Lamp (MIL), also known as the "Check Engine" light. This issue can prevent the MIL from illuminating when there is a fault in the vehicle's systems. Our comprehensive blog post will provide you with detailed instructions on diagnosing and repairing the MIL control circuit for accurate warning indications.

P0651 – PCM Voltage Out of Tolerance Condition on the 5-volt Reference Circuit:
Similar to the previous code, the P0651 code indicates a voltage out-of-tolerance condition on the PCM's 5-volt reference circuit. This issue can lead to sensor-related problems and inaccurate engine operation. Our auto-tuning blog will guide you through the process of identifying and resolving this voltage issue for optimal PCM performance.

P0654 – Engine RPM Output Circuit Malfunction:
When there is a malfunction in the engine RPM output circuit, the P0654 code is triggered. This issue can lead to inaccurate RPM readings or irregular engine operation. Our blog post will provide you with a detailed explanation of the engine RPM output circuit and guide you through the necessary steps to diagnose and rectify the malfunction for proper engine performance.

P0655 – Engine Hot Lamp Output Control Circuit Malfunction:
The P0655 code indicates a malfunction in the engine hot lamp output control circuit. This issue can prevent the engine hot lamp from illuminating when the engine temperature is too high, potentially leading to engine damage. By following our blog's instructions, you will learn how to diagnose and repair the engine hot lamp output control circuit, ensuring timely warnings and preventing overheating.

P0656 – Fuel Level Output Circuit Malfunction:
When there is a malfunction in the fuel level output circuit, the P0656 code is triggered. This issue can lead to inaccurate fuel level readings on the dashboard, causing inconvenience or running out of fuel unexpectedly. Our comprehensive blog post will guide you through the process of diagnosing and resolving the fuel level output circuit malfunction for accurate fuel level indications.

P0660 – Intake Manifold Tuning (IMT) Valve Solenoid Control Circuit:
The P0660 code relates to a malfunction in the control circuit of the Intake Manifold Tuning (IMT) valve solenoid. This issue can impact the engine's air intake and performance, resulting in reduced power or rough idling. By visiting our auto-tuning blog, you will gain a comprehensive understanding of the IMT valve solenoid control circuit and learn how to diagnose and rectify the malfunction for optimal engine operation.

P0661 – Intake Manifold Tuning (IMT) Valve Solenoid Control Circuit Low Voltage:
If the voltage in the control circuit of the IMT valve solenoid falls below the expected range, the P0661 code is triggered. This issue can disrupt the operation of the IMT system, leading to compromised engine performance. Our blog will provide you with detailed instructions on diagnosing and resolving the low voltage condition in the IMT valve solenoid control circuit for optimal engine efficiency.

P0662 – Intake Manifold Tuning (IMT) Valve Solenoid Control Circuit High Voltage:
In contrast to the previous code, the P0662 code suggests a high voltage condition in the control circuit of the IMT valve solenoid. This issue can cause excessive current flow, potentially damaging the IMT valve or other electrical components. Our blog will guide you on diagnosing and resolving this high voltage issue to ensure proper IMT system operation and prevent further damage.

P0685 – Engine Controls Ignition Relay Control Circuit (PCM):
The P0685 code indicates a malfunction in the ignition relay control circuit of the Engine Control Module (ECM). This issue can lead to starting problems or intermittent engine operation. By following our blog's instructions, you will learn how to diagnose and repair the engine controls ignition relay control circuit for reliable engine ignition.

P0691 – Cooling Fan Relay Control Circuit Low Voltage:
When the voltage in the cooling fan relay control circuit drops below the expected range, the P0691 code is triggered. This issue can result in inadequate cooling of the engine, leading to overheating. Our comprehensive blog post will guide you through the process of identifying the low voltage source and resolving the cooling fan relay control circuit problem effectively.

P0692 – Cooling Fan Relay Control Circuit High Voltage:
Contrary to the previous code, the P0692 code indicates a high voltage condition in the cooling fan relay control circuit. This issue can cause excessive current flow, potentially damaging the cooling fan or other electrical components. Our blog will provide you with expert guidance on diagnosing and resolving this high voltage issue to ensure proper cooling system functionality and

P0693 – Cooling Fan Relay Control Circuit High Voltage:
Similar to the previous code, the P0693 code signifies a high voltage condition in the cooling fan relay control circuit. This issue can lead to excessive current flow, potentially damaging the cooling fan or other electrical components. Our blog post will provide you with detailed instructions on diagnosing and resolving this high voltage issue to ensure optimal cooling system performance.

P0694 – Cooling Fan Relay Control Circuit High Voltage:
The P0694 code indicates a high voltage condition in the cooling fan relay control circuit. This issue can cause excessive current flow, potentially damaging the cooling fan or other electrical components. By visiting our auto-tuning blog, you will gain valuable insights into diagnosing and rectifying this high voltage issue, ensuring proper cooling system operation.

By following the tips and guidelines provided in our comprehensive blog post, you will be equipped with the knowledge and understanding necessary to diagnose and resolve various DTC codes related to control modules and output controls. Our step-by-step instructions will help you address these issues effectively, ensuring optimal performance and functionality of your vehicle.

For more detailed information and solutions to DTC codes related to control modules and output controls, we invite you to visit and follow our Electronic Repair Company blog at https://www.electronicrepairegypt.com/auto-tuning-blog. Our blog is dedicated to providing valuable insights and expert advice on automotive repairs and troubleshooting, helping you keep your vehicle in top shape.

Remember, proper diagnosis and repair of DTC codes require technical expertise and, in some cases, specialized tools. If you are uncertain or unable to address the issues on your own, it is recommended to consult a qualified automotive technician or repair professional.

Stay tuned to our blog for regular updates, informative articles, and expert advice on automotive repairs and maintenance. We are here to assist you in keeping your vehicle running smoothly and efficiently.

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