INFINITI Q45 Cruise Control Isn't Working

Troubleshooting Common Issues with INFINITI Q45 Cruise Control and How to Restore Functionality

Find Repair Location
Reviewed by
Andrew Hajjar
Written by RepairPal Car Genius
Updated January 14, 2025
0%
30% chance it's the
Sensor
0%
25% chance it's the
Control Module
0%
25% chance it's the
Throttle
0%
20% chance it's
Something else
The most common reasons a INFINITI Q45 cruise control isn't working are failed control module, sensor or switch issues, or throttle actuation problems.
  • Sensor: A faulty or malfunctioning sensor can lead to incorrect readings, causing issues with engine performance or other systems relying on accurate data.
  • Control Module: A faulty control module can lead to erratic vehicle behavior or failure of various electronic systems due to improper signal processing.
  • Throttle: A faulty throttle body or a defective accelerator pedal position sensor may be causing inconsistent throttle response.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a INFINITI Q45 cruise control isn't working?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

When the throttle position sensor fails, the engine's computer tends to overcompensate with fuel, leading black exhaust coming from the tailpipe. There is a strong possibility of engine misfires, and the check engine light will come on.

Throttle position sensors can also develop "dead spots," or certain places along the throttle curve where it doesn't get a reading. When this happens, the above symptoms can occur but then stop when you further press or let off the gas pedal.

When the vehicle speed sensor fails or the wiring harness prevents signal transmission, the speedometer is the first thing that will stop functioning properly. This can be an intermittent issue where the speedometer only works occasionally, the speedometer may cease all function, or the speedometer may read erratically or incorrectly. Also, the traction control and anti lock brake warning lights specific to each vehicle may be illuminated, depending on the design of those systems. You may notice the vehicle hesitate to accelerate, cruise control will not function properly, and the vehicle may not shift properly through all of the gears.

In the event that a wheel speed sensor fails, the ABS, traction control system (TCS) and manufacturer specific stability control system lights will illuminate, informing the driver that the systems are disabled. The vehicle will be more prone to tire slip, and normal driving patterns may need to be adjusted to correct for the loss of computer control. On older vehicle's, the speedometer can be affected, causing illumination of the check engine light as well.

If the cruise control refuses to turn on at all, the actuator could be at fault. Likewise, if the cruise control stays on but does not maintain a consistent speed, the problem could be a bad actuator. In extreme cases, a malfunctioning actuator could cause the throttle to stick and prevent the vehicle from slowing down. These symptoms may point to a bad actuator. They may also point to other problems with the cruise control and related systems.

The cruise control switch can cause complete failure of the cruise control feature, but in a lucky scenario only partial functionality will be lost. This means that the cruise control may come on, but that it will not increase in speed automatically, or the cancel button does not work leading the driver to cancel cruise control with the foot brake. In some vehicles, the cruise control light may illuminate, or a warning message may be displayed due to lack of functionality.

Troubleshooting Cruise Control Issues in an INFINITI Q45

When troubleshooting cruise control issues in your INFINITI Q45, begin with a systematic diagnostic approach that prioritizes simpler fixes. Start by checking the cruise control components, including the Control Module, Sensor, and Throttle, as these are often the culprits behind malfunctioning systems. Next, utilize an OBD-II scanner to retrieve Diagnostic Test Codes (DTC), which can provide valuable insights into the specific issues affecting your vehicle. Pay attention to common problems, such as the cruise control failing under certain conditions, which may indicate environmental factors at play. Additionally, inspect the fuse and brake pedal switch, as a blown fuse or a faulty switch can easily disrupt the cruise control functionality. If these initial checks do not resolve the issue, consider seeking professional assistance for a more thorough diagnosis, particularly if you suspect deeper electronic or sensor-related problems. By following this structured approach, you can effectively identify and address the root causes of cruise control issues in your INFINITI Q45, making your DIY troubleshooting efforts more efficient and successful.

Troubleshooting Cruise Control Issues in an INFINITI Q45

When troubleshooting cruise control issues in your INFINITI Q45, it's essential to understand the common problems that may arise within the system. One frequent culprit is the control module, which can malfunction and disrupt the cruise control's operation. Additionally, sensors and the throttle can also contribute to these issues, so checking their functionality is crucial. Another common problem lies with the brake pedal switches; if these switches are faulty, they can inadvertently disable the cruise control, preventing it from engaging properly. It's also wise to look for any Diagnostic Test Codes (DTC) that may indicate specific issues within the system, as these codes can guide your troubleshooting efforts. Furthermore, be aware that a blown fuse, a malfunctioning brake light, or even a check engine light can signal underlying problems that affect cruise control functionality. For a more comprehensive diagnosis, utilizing a factory scan tool can provide deeper insights into the ABS/VDC and ICC systems, helping you pinpoint the exact cause of the malfunction. By systematically addressing these common issues, you can effectively troubleshoot and potentially resolve cruise control problems in your INFINITI Q45.

Why is the Cruise Control Not Working in an INFINITI Q45?

When the cruise control in your INFINITI Q45 is not functioning, it’s crucial to address the problem promptly, as neglecting it can lead to safety risks and further vehicle damage. Common culprits include a malfunctioning control module, faulty sensors, or issues with the brake pedal switches, which can prevent the cruise control from engaging or disengaging properly. Additionally, a blown fuse or problems within the throttle control system may also be at fault. If the brake release switch fails to operate correctly, it can cause the cruise control to remain engaged, posing a significant safety hazard. Diagnosing these issues early not only ensures your vehicle operates safely but also helps avoid costly repairs down the line. Therefore, if you notice any symptoms of cruise control failure, it’s advisable to investigate the underlying causes as soon as possible.

You’ve got options with RepairPal

Whether you need a more accurate auto repair estimate or help finding a reputable shop in your area, we’ve got you covered.