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

P0575 Cruise Control Input Circuit

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. At GM and Saab P0575 is not an analogue circuit fault but the plausibility of the CAN message carrying the button state from the body module: wrong checksum or rolling count in 9 of 17 messages (2014: 3 of 10 frames). Other makers use it literally as a general input circuit fault with P0576/P0577.

Likely causes

Body module faulty or software (invalid message)
CAN disturbance (connectors, wires, termination)
Steering wheel switch fault (B3794 in the body module)
Engine module

Symptoms

  • Cruise control inoperative, possibly further U codes
  • Cruise control locked out
  • No check engine light, engine runs normally

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–900
Time1–3 h

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

Parts involved

body control modulecan buscruise control switchengine control module

Related codes

P0576P0577P0564P0578P0579

References: gsi.ext.gm.com, gsi.ext.gm.com, saabwisonline.com.