P0590: Cruise Control Multi-Function Input B Circuit Stuck
What to do
Driveable; cruise control will refuse to engage. Do not attempt to use it until repaired.
What this code means
The second cruise control input is reading as permanently pressed — the counterpart of P0578 on the redundant circuit. The module disables cruise control rather than acting on an input it knows is stuck, which is the correct response.
Likely causes
Start here
- Faulty cruise control switch · moderate
- Water ingress into connector · easy
Less common
- Signal wire shorted to ground · moderate
- Corroded switch contacts · easy
Symptoms
Components involved
Information, not instruction
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Community experience
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