C1109 code — how to fix error fast

If you get a code C1109 after a diagnostic scan of your car, chances are that you are pretty worried about driving it while the code is on. While it’s true that it’s not safe to do so, it’s more important to get to the C1109 code meaning and fix the issue that triggered the code if you wish to keep driving regularly.

That’s why our team wanted to help you since it’s sometimes difficult to obtain information from professionals unless you know exactly the mechanic to turn to. Our guide will give you an overview of why the code happens, and help you figure out the diagnostic and fixing methods you can apply to identify and solve the problem.

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What does the C1109 code mean?

The C1109 code is a diagnostic trouble code that indicates a problem with the ABS pump motor circuit. When this code appears, it means that there is a malfunction in the ABS pump motor circuit, which could lead to problems with the braking system.

Understanding this code is essential because it can help you diagnose and fix problems with the braking system before they become more severe. In this article, we will cover the causes of the C1109 code, how to diagnose it, and how to fix it.

What causes the C1109 code?

While the code is usually triggered by a faulty ABS system component, it’s not necessarily the case. To properly tackle the issue, you’ll need some more information on the usual causes of the code, so our team will deliver those right away:

Malfunctioning ABS pump motor

The ABS pump motor is responsible for maintaining the pressure in the ABS system. If the pump motor fails, it can cause a loss of pressure in the system, which can trigger the C1109 code.

Symptoms that may be present with a malfunctioning ABS pump motor include a soft or spongy brake pedal, a pulsating brake pedal, and a loss of brake pressure.

Damaged or corroded wiring in the ABS pump motor circuit

The wiring in the ABS pump motor circuit can become damaged or corroded over time. This can cause a loss of signal to the ABS control module, triggering the C1109 code.

Symptoms that may be present with damaged or corroded wiring in the ABS pump motor circuit include intermittent ABS operation and a loss of ABS functionality.

Defective ABS control module

The ABS control module is responsible for controlling the ABS pump motor. If the control module fails, it can trigger the C1109 code.

Symptoms that may be present with a defective ABS control module include an ABS warning light that stays on, a loss of ABS functionality, and intermittent ABS operation.

Low brake fluid level

Low brake fluid level can cause a loss of pressure in the ABS system, triggering the C1109 code.

Symptoms that may be present with low brake fluid level include a soft or spongy brake pedal, a pulsating brake pedal, and a loss of brake pressure.

Failed wheel speed sensor

The wheel speed sensors are responsible for providing the ABS control module with information about the speed of each wheel. If a wheel speed sensor fails, it can trigger the C1109 code.

Symptoms that may be present with a failed wheel speed sensor include an ABS warning light that stays on, a loss of ABS functionality, and intermittent ABS operation.

Which car models does the C1109 code affect the most?

While it’s difficult to say which specific car models are most likely to be affected by this code, it could potentially impact any car that uses a hydraulic brake booster and has an ABS system. Some car manufacturers have had more issues with ABS systems than others, so it may be worth checking if your car brand has had any recalls related to the ABS system, so here’s our list:

• Nissan Murano: Nissan is one manufacturer that has had several recalls related to ABS issues, including the hydraulic brake booster pressure sensor which caused many drivers of the Nissan Murano to retrieve the C1109 code.
• Nissan Rogue: This one is yet another vehicle that is reported to have issues with the code C1109 and it usually happens due to problems with the ABS circuit.
• Nissan Pathfinder: Just like the Murano, the Pathfinder is another model that struggled with the code C1109 because of the faulty brake booster.

How to diagnose the C1109 code

There are many ways of diagnosing the C1109 code since every possible cause we listed may require a specific approach to figure it out. So, here’s our list of the most commonly used diagnostic methods to read the code and pinpoint the exact culprit triggering it:

Using an OBD2 scanner

You can use a scan tool to read the diagnostic trouble codes (DTCs) stored in your car’s onboard computer. Code C1109 will appear in the list of codes if there is an issue with the hydraulic brake booster pressure sensor circuit.

Hyrdaulic system test

A hydraulic system test can be performed to check the pressure and flow of brake fluid through the system. This can help identify any issues with the hydraulic brake booster pressure sensor circuit.

Electrical testing

An electrical test can be performed on the hydraulic brake booster pressure sensor circuit to check for any issues with wiring or connections.

How to fix the C1109 code

Fixing code C1109 will typically involve repairing or replacing the hydraulic brake booster pressure sensor circuit. Here are some of the main ways that this can be done:

Replace the hydraulic brake booster pressure sensor

If the issue is with the pressure sensor itself, the mechanic may recommend replacing it with a new one. This will involve removing the old sensor and installing a new one in its place.

Repair damaged wiring or connections

If there is an issue with the wiring or connections in the hydraulic brake booster pressure sensor circuit, the mechanic may need to repair or replace these components. This may involve splicing in new wires, replacing damaged connectors, or other similar repairs.

Replacing other ABS-related components

In some cases, issues with the hydraulic brake booster pressure sensor circuit may be related to other components of the ABS system. For example, if there is a leak in the system or a problem with the hydraulic pump, this could impact the performance of the pressure sensor.

How to prevent the C1109 code

Preventing the C1109 code requires routine maintenance of the braking system. Here are a few tips to help prevent the code:

• Check the brake fluid level regularly and refill it as needed.
• Inspect the wheel speed sensors for damage or corrosion and replace them as needed.
• Have the ABS system inspected regularly for signs of wear or damage.
• Follow the manufacturer’s recommended maintenance schedule.

By following these preventative measures, you can help ensure that the braking system remains in good working order and avoid problems with the ABS pump motor circuit.

Our take

Ultimately, the C1109 code can be pretty dangerous to leave, and just keep on driving since it may affect your driving safety. If the ABS system fails to engage on slippery roads, it could be more difficult to keep your vehicle in the lane.

So, we recommend you repair the issue by using the methods listed in this guide so you can properly address the code and prevent it from happening again.