The purpose of this article is to provide an overview of a warning that is commonly encountered in Ford vehicles, the “Park Brake Limited Function Service Required.” You’re going to learn what it means, why it happens, and how to fix it?
This warning message is caused by a number of factors. Before we delve deeper into them, A parking brake is important on your Ford, and you should know what it is.
Older models commonly refer to parking brakes as hand brakes. This device stops your vehicle from rolling when you park it by locking the rear wheels. Electric parking brakes are now available on newer Ford models.
An Explanation of the Ford electric parking brake
As opposed to the old mechanical parking brake or handbrake, the Ford electric parking brake is now used. When you want to keep a vehicle stationary, it attaches electrically to the rear brakes.
In the center console, usually near the gear shifter, is a switch that operates the electric parking brake.
By pulling up on the parking brake switch, the parking brake will be applied. Once the brake system has been set, the brake system warning light will flash.
As you press down the brake pedal, your foot should automatically release the parking brake.
The release mechanism will also operate automatically if you press the accelerator and the driver’s door is closed.
There are a few advantages to using an electric parking brake rather than the old manual one.
The mechanical brake handle can be removed to create more space between the seats. Also, it is possible to automatically release the clutch upon starting, which makes it easier to start the vehicle on steep hills.
“Park Brake Limited Function Service Required”: What Does It Mean?
You have now gained an understanding of what a parking brake on your Ford does. What does the message “park brake limited function service required” mean?
Your Ford’s electric parking brake system has a problem, so this message shows. Electric parking brakes operate with the assistance of electricity as well as the brake system.
The system automatically enters a limited functionality mode in the event of a fault with the parking brake motors, ABS, or Battery voltage (see leading causes below).
There may be a problem with the parking brake if this message appears.
Causes of Park Brake Limited Function
Due to the fact that your vehicle uses an electric park brake, this alert can occur for a number of reasons.
I have narrowed it down to the following, though, based on my experience as a mechanic:
1. Bad wiring harness for parking brakes:
Bad wiring harnesses are the main cause of the message “Park brake limited function”. This alert can appear due to problems with the wiring in your Ford’s parking brake system.
Age, moisture, or other factors may damage or corrode wires. Park brake signals cannot be processed in this scenario since the brakes are not connected to the computers of the vehicle.
Wiring harnesses are relatively inexpensive, so this is a good thing. It will cost you between $120-150 to get both sides.
2. An actuator switch that has been damaged:
A bad parking brake actuator switch is another common cause of the message. In order to activate or deactivate the parking brake, you must press the actuator switch manually.
Wear, contaminants, or electrical problems can cause this switch to fail internally. A dirty or burned switch contacts can prevent the circuit from being properly closed when pressed, for instance. Activation signals cannot be properly sent to the parking brake control module if the parking brake switch is damaged.
3. A defective parking brake motor is to blame:
An electric motor powers the parking brake pads on Ford cars with electric parking brakes. Normal wear and internal damage can lead to motor failure over time.
The motors will not function properly if the windings get burned, the gears get stripped, the rotors get stuck, or excessive friction occurs. The parking brake system becomes limited when one or both motors fail. There may be a problem releasing or engaging the parking brake fully.
4. An insufficient battery voltage:
In addition to a weak battery, a park brake limited function warning can also be caused by a faulty park brake mechanism. Deficiencies in battery voltage are necessary for the parking brake motors to work properly (about 12.6 volts).
When the system voltage is low, weak battery connections, faulty alternators, defective batteries, or parasitic electrical drains may contribute to the problem. The parking brakes may not operate properly if the supply voltage drops too low.
5. A failed ABS module:
Electric parking brakes are controlled by built-in logic within the anti-lock brake system (ABS). In the event of a malfunctioning ABS module, the parking brake motors will be unable to communicate with each other.
The ABS module should be scanned for diagnostic trouble codes to identify any problems with its internal circuitry. It is sometimes possible to repair or reprogram a faulty ABS module. If not, it must be replaced.
6. Failure of the brake calipers:
Lastly, damaged brake calipers are one of the leading causes of “Park brake limited function service required”. It is possible for the electric parking brake to not engage fully when there is a problem inside the rear brake calipers. Damaged seals, dirty friction pads, and stuck pistons are all factors that can affect your parking brake
Park Brake Limited Function Warning: How to fix and reset it
I’ll show you the steps you can take to fix and reset the alert now that we’ve talked about the causes.
Battery testing and charging
I recommend checking your battery as a first step. Check the voltage and cold cranking amps of the battery with a simple battery test.
Battery failure can be repaired by recharging or replacing it. Parking brake issues related to low voltage can likely be resolved with this inexpensive first step.
Wire harnesses need to be checked
In most cases, this warning occurs as a result of a damaged park brake wiring harness. The wiring harness is the next thing to check.
Examine the wiring harness and connectors of the parking brake to determine whether they have been damaged, corroded, or have loose connections. In the event that wiring has been damaged, it should be repaired or replaced.
Analyze ABS module problems
Check the ABS module for trouble codes at the dealer or repair shop. You can get the root of the problem by looking at diagnostic trouble codes. ABS modules may need to be reprogrammed or replaced.
The switch on the actuator needs to be replaced
The parking brake actuator switch should be replaced if it has been determined to be faulty. If necessary, the switch will need to be recalibrated.
Parking brake motors must be repaired
It is necessary to repair or replace a defective parking brake motor if the motors are malfunctioning. Following the installation of the new motor, you may need to adjust the brake calipers.
