Powertrain, generic · Vehicle speed, idle control and auxiliary inputs

P056C Cruise Control Cancel Signal

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

Cruise control buttons are almost always a resistor ladder on one or two signal lines, each button giving its own voltage; the module reading it (GM and Saab from about 2010: the body module; FCA: steering column module or PCM) sends the button state to the engine module over CAN. CARB names cruise control as the example of an emission-neutral diagnosis – it is simply switched off – so GM lists all these codes as type C and Ford as non-MIL: no warning lamp, the engine runs normally. P056C concerns the cancel button, which interrupts control but keeps the set speed – unlike the off signal P0566. GM (from about 2015) sets it when the button is reported pressed for over 20 s. Older code lists still show it as reserved.

Likely causes

Cancel button stuck or faulty
Moisture or wear in the steering wheel switch
Contact resistance in clockspring or steering wheel connector
Body module or cruise module

Symptoms

  • Cruise control cannot be engaged or cancels immediately
  • Cruise control locked out
  • No check engine light, engine runs normally

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–400
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

cruise control switchclockspringswitch wiringbody control module

Related codes

P0566P0565P0567P0568P0571

References: gsi.ext.gm.com, saabwisonline.com, law.cornell.edu.