Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
General Information
Frozen values are parameter values that are stored when a diagnostic trouble code (DTC) is stored.
Not all the parameters described need to be implemented in the control module. This varies from system to system. Parameters can also vary depending on which type of transmission the car has.
Certain parameters can be displayed without a value or with implausible values. This can occur if the control module has not stored a value, when a base value has been stored instead or if the parameter is received via the CAN network when there is an error on the CAN network. For example, the transmission speed value may be excessive if the fault occurs for the transmission speed sensor.
Definition of an operating cycle
The definition of an operating cycle varies depending on the software version.
Alternative definitions
- The ignition has been switched off, then switched on and finally switched off again
- The ignition has been switched off, the engine started and finally the ignition switched off again
- The ignition has been off, the engine started, the car driven at a speed above 30 km/h for more than 3 minutes and finally the ignition switched off again.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.