The P0593: Cruise Control Multi-Function Input ‘B’ Circuit High refers to a fault where the cruise control system detects high voltage in the multi-function input ‘B’ circuit. This can result from a faulty switch, high voltage in the circuit, or wiring issues, leading to improper cruise control operation.
P0593 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0593: Cruise Control Multi-Function Input ‘B’ Circuit High |
| Is it serious? | No, but it can affect the cruise control system’s performance. |
| Possible causes | – Faulty multi-function input ‘B’ switch – High voltage in circuit – Wiring issue |
| How to diagnose? | – Test multi-function input ‘B’ switch for voltage – Inspect wiring and connectors – Test cruise control module |
P0593 Meaning
The P0593 code indicates that the cruise control system has detected a higher-than-expected voltage in the multi-function input ‘B’ circuit. This may occur due to problems with the input switch, excessive voltage, or wiring issues. If left unaddressed, this can impair the cruise control system’s operation.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional related codes that may provide more information. | OBD-II Scanner |
| Test the Multi-Function Input ‘B’ Switch | Use a multimeter to measure the voltage in the multi-function input ‘B’ switch and ensure it is within the recommended range. | Multimeter |
| Inspect Wiring and Connectors | Inspect the wiring and connectors associated with the input switch for damage, corrosion, or loose connections. | Flashlight, Multimeter |
| Test the Cruise Control Module | Verify that the cruise control module is functioning correctly and not receiving excessive voltage. | Diagnostic Tool, Multimeter |
| Clear the Code and Test | After completing repairs, clear the code using an OBD-II scanner and test the vehicle to confirm the issue is resolved. | OBD-II Scanner, Vehicle Manual |
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