P0585
Cruise Control Multi-Function Input "A"/"B" Correlation
- Severity
- Medium
- Driving
- Drivable — book it in
The two cruise control multi-function inputs disagree. Two circuits are used so that a single failure can be caught, and this code is that check working - one of the pair is wrong and the module cannot tell which, so it disables cruise control rather than act on an input it cannot trust.
Possible causes
- CommonFailed cruise control switch or stalk
- CommonWiring fault in the steering column or console
- CommonDamaged clock spring, on steering-wheel-mounted controls
- CommonCorroded or disturbed connector
- PossibleBrake or clutch switch fault preventing cruise from engaging
- RareFailed control module input
What you might notice
- Cruise control will not engage
- Cruise control cancelling on its own
- Set, resume or cancel not responding
- Cruise warning message
- Check engine light on
What to check, in order
- Watch both inputs together while operating each control. The one that does not follow the other is the fault.
- Watch the cruise control switch states on the live data screen while operating each control.
- Check the brake and clutch switches. Cruise control will not engage while the module thinks the brake is pressed, so a brake switch fault presents as a cruise control fault.
- On steering-wheel controls, suspect the clock spring - horn or airbag faults alongside confirm it.
- Inspect the connector if the column or console has been worked on.
- Confirm ordinary driving is unaffected, in which case this can wait.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Vehicle speed control, idle control and auxiliary inputs
P0500P0501P0502P0503P0504P0505P0506P0507P0508P0509P0510P0511P0512P0513P0514P0515P0516P0517P0518P0519P0520P0521P0522P0523P0524P0525P0526P0527P0528P0529P0530P0531P0532P0533P0534P0535P0536P0537P0538P0539P0540P0541P0542P0543P0544P0545P0546P0547P0548P0549P0550P0551P0552P0553P0554P0555P0556P0557P0558P0559P0560P0561P0562P0563P0564P0565P0566P0567P0568P0569P0570P0571P0572P0573P0574P0575P0576P0577P0578P0579P0580P0581P0582P0583P0584P0585P0586P0587P0588P0589P0590P0591P0592P0593P0594P0595P0596P0597P0598P0599