What Is the P1633 Code?
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The diagnostic error code, P1633, indicates an issue in the power supply to the KAM (Keep Alive Memory) system. This is a manufacturer-specific code and as such, the precise meaning can change from model to model. This particular interpretation applies to a range of Ford vehicles.
If your vehicle flags this code and you are uncertain whether this meaning applies, consider the Kelley Blue Book (KBB) OBD-II database for further information. This free resource includes information on all currently used diagnostic error codes, their potential meanings, and the vehicles they apply to.
The P1633 diagnostic code as displayed in Ford vehicles indicates that there is a problem with the power supply to the KAM system in your vehicle. In particular, this code means there is low voltage reaching the keep-alive memory system which is responsible for storing key data about the car’s condition and usage. Low voltage to the KAM system can also impact the powertrain control module (PCM) and engine control module (ECM).
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What Are the Symptoms of a P1633 Code?
Because this issue relates to the internal memory of your car, there are likely to be few visible or audible symptoms of a P1633 code. This can make it hard to identify and deal with the problem quickly. Nonetheless, there are some symptoms that you can be aware of. These include but are not limited to:
- Activation of the check engine light
- Incorrect indication of fuel reserves
- Lack of fuel usage indicator
- Lack of mileage indicator
- Incorrect mileage indicator
What Are Some Causes of a P1633 Code?
Several factors can lead to low voltage levels in the KAM system in a car and the activation of the P1633 diagnostic code. Most of these are electrical, caused by low battery. If the battery is old or some parasitic draw drains the battery below 9.7 volts, the modules will not behave as designed.
Additionally, certain kinds of physical damage can also cause this issue. These include:
- Open keep-alive power (KAPWR) circuit
- Damaged or faulty connectors
- Damaged or faulty wiring
- Damaged or faulty circuits
- Faulty powertrain control module (PCM)
How Serious Is the P1633 Code?
The P1633 code should be considered moderately severe because, while it may not impact drivability, it impacts the PCM and ECM and will make it hard for your car to collect and store accurate data about its condition and usage. This can impact many aspects of day-to-day usage, including the estimations of fuel usage and mileage.
Can I Still Drive with a P1633 Code?
It is possible to drive a car that has activated a P1633 code, but you may have issues with damage and fuel indicators. This can lead to avoidable issues and lower drivability but is not likely to have a huge impact on the ability to safely operate your vehicle. Nonetheless, it is best to seek a solution quickly as such power issues often indicate damage or degradation of the wiring and circuitry in a car. If these issues spread, you may find that your ignition or TAC system power supply begins to suffer. This will pose more significant safety risks.
How Easy Is It to Diagnose a P1633 Code?
It can be difficult to diagnose the precise cause of a P1633 code because of the placement of the components and the low visibility of many of the symptoms. However, a professional should be able to identify all contributing factors by using a process of elimination and specialist diagnostic tools.
How Difficult Is It to Inspect a P1633 Code?
The placement of the components of the KAM system can make physical examinations and repairs delicate. A professional will generally check the following components and repair or replace damaged items:
- Battery terminals
- Battery cables and connectors
- Engine control (EC) system and wiring
- Keep-alive power (PAPWR) module
- Electronic EC harness
They are likely to use tools, such as a digital multimeter, to inspect the condition of some of these components. A mixed solution involving repairs or replacements of multiple components may be necessary.
Need Additional Help with Your P1633 Code?
Issues with the KAM system within a car can be very serious as the keep-alive memory system is responsible for monitoring and storing information about your car’s usage. Without this system, you will not receive key notifications about fuel tables (or fuel adaptations) and battery condition, amongst others. Issues with the KAM can result in the loss of your vehicle’s fuel delivery strategy.
If you feel there are issues at work that are impacting your car’s safety and drivability, however, it is generally best to seek professional help. KBB also has a free service center locator that will help you to identify reputable auto repair centers in your local area. Acting quickly is your best chance of finding a simple and affordable solution.
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