Technical Description of OBD-II Trouble Code
Issue with Cruise Control – Vehicle Speed Too High
What does that signify?
This is a standard diagnostic trouble code (DTC) that applies to OBD-II vehicles equipped with cruise control. This can include vehicles from various manufacturers such as Peugeot, Ford, Nissan, Chevrolet, Hyundai, VW, Audi, Citroen, etc. While it is a generic code, the specific repair steps may vary depending on the year, make, model, and powertrain configuration of the vehicle.
Within the cruise control system, there are multiple functions. In addition to setting a specific vehicle speed and maintaining it automatically using various sensors, switches, modules, and other components, you can also electronically modify the speed (e.g. “set -” and “resume +”), temporarily adjust the speed while storing the previous speed (e.g. when passing vehicles or unexpectedly slowing down), and perform other actions.
Since most of the functions mentioned in the description of code P0574 and related codes (P0565, P0566, P0567, P0568, P0569, etc.) are contained within a single switch/component, it should be relatively easy to locate the mechanical inputs (e.g. buttons, switches, talks) involved. Some common names for this component(s) include Multi-function switch, Steering wheel controls, Cruise control switch, Cruise control module, and Accessory switch.
In the case of this code, the Engine Control Module (ECM) has detected a malfunction within the signal circuit. In simple terms, something went wrong within the circuit of the mentioned function.
When the ECM detects a signal malfunction in one or more of the cruise control functions, it illuminates the Check Engine Light (CEL) with code P0574 and/or related codes. Most likely, the use of the affected function will be disabled or behave abnormally.
Code P0574 is triggered when the ECM detects that the vehicle speed is significantly higher than the desired speed set by the cruise control system.
Here is an example of cruise control buttons on a steering wheel:
What is the severity of this DTC?
The severity of this DTC is considered moderately low. Even if the entire functionality of the cruise control system is lost, it is still possible to safely drive the vehicle. However, neglecting any electrical issue for an extended period of time may result in further damage.
What are some of the symptoms of the code?
Symptoms of a P0574 trouble code may include:
What are some of the common causes of the code?
The causes of the P0574 code may include:
What are some P0574 troubleshooting steps?
Basic Step #1
The first step is to visually inspect the cruise control switch/module. Check for missing buttons, buttons stuck due to cola or other substances, loose buttons that do not make proper electrical connections, and any contamination that could potentially damage the buttons. Also, make sure to document all malfunctions or abnormalities in the cruise control functions.
Basic Step #2
Check if the cruise control light comes on in the instrument cluster when the cruise control is manually activated. If not, verify if there is a fuse for the circuit and replace any blown fuses with new ones approved by the manufacturer. Refer to the vehicle’s service manual for fuse information.
Basic Step #3
To access the harness to the cruise control switch/module, you may need to remove certain dash parts such as the steering column shroud and airbag module in the steering wheel. To pinpoint the specific wire involved in the fault, you will need a proper wiring harness for your vehicle. These harnesses can vary significantly, so always consult the appropriate service information before performing any invasive actions.
Basic Step #4
Ensure that the Anti-lock Braking System (ABS) is in good working order and that there are no ABS lights illuminated on the dashboard. The ABS system uses various sensors, including speed sensors, which, if malfunctioning, could cause the computers to incorrectly perceive the vehicle’s speed.
