What causes fault code P056B?

• Most likely: Faulty clockspring (spiral cable) in the steering wheel • Likely: Mechanically stuck or electrically defective control switch (Coast/Set-) • Possible: Damaged wiring or corrosion in connectors between steering wheel and ECM • Rare: Software glitch or internal fault in Steering Wheel Module (SWM) or ECM

Powertrain (Engine & Gearbox)Standard EOBD

P056B - Cruise Control Coast Signal - Implausible

Q: What are the symptoms of fault code P056B?

• Cruise control cannot be engaged • Cruise control disengages spontaneously during driving • Check engine light (MIL) or 'Cruise Control Service Required' message displayed • No direct driveability issues other than loss of cruise control function

Q: How do you fix fault code P056B?

STEP 1: Check if the button is mechanically stuck. Clean with electronics cleaner if necessary. Check fuses related to the steering wheel module (SWM). STEP 2: Use a diagnostic tool to read Live Data. Check if the button status changes from 'OFF' to 'ON' when pressed. If status is stuck at 'ON', proceed to testing. STEP 3: Measure resistance across the switch assembly. For analog systems: Verify 5V reference and ground. When pressed, resistance should change to a specific OEM value (e.g., 200-1000 Ohms depending on model). STEP 4: If values at the switch are correct but incorrect at the steering column, replace the clockspring. If signals reach the ECM correctly but the code persists, a software update or ECM diagnosis is required.

Last updated:1 February 2026

Related:Clockspring, Cruise Control Switch, Steering Wheel Module (SWM), Engine Control Module (ECM)

System

Powertrain (Engine & Gearbox)

Related Fault Codes

P0500

Vehicle Speed Sensor (VSS) 'A' Range/Performance

P0501

Vehicle Speed Sensor 'A' Range/Performance

P0502

Vehicle Speed Sensor 'A' Circuit Low Input

P0503

Vehicle Speed Sensor (VSS) Intermittent/Erratic/High

Technical Description

P056B is stored when the Engine Control Module (ECM) detects an implausible input signal from the Cruise Control 'Coast' or 'Set-' function. The system monitors the voltage or data frame from the steering wheel switches or the cruise control stalk. If the signal suggests the button is stuck for an abnormally long duration, or if the signal value does not correlate with the expected voltage level (in analog systems) or checksum (in CAN-based systems), this code is triggered. This is a safety measure to prevent unintended deceleration or acceleration via the cruise control system.

Possible Causes

Faulty clockspring (spiral cable) in the steering wheel

Mechanically stuck or electrically defective control switch (Coast/Set-)

Damaged wiring or corrosion in connectors between steering wheel and ECM

Software glitch or internal fault in Steering Wheel Module (SWM) or ECM

Symptoms

Cruise control cannot be engaged

Cruise control disengages spontaneously during driving

Check engine light (MIL) or 'Cruise Control Service Required' message displayed

No direct driveability issues other than loss of cruise control function

Do you also have
other fault codes?

See how P056B connects with your other fault codes. Our advanced analysis tool identifies causal relationships and root causes directly.

Analyze multiple codes

P056B - Cruise Control Coast Signal - Implausible

Related Fault Codes

Technical Description

Possible Causes

Symptoms

Recommended Solution

Workflow

Mechanic's Tip

Do you also have
other fault codes?

P056B - Cruise Control Coast Signal - Implausible

Related Fault Codes

Technical Description

Possible Causes

Symptoms

Recommended Solution

Workflow

Mechanic's Tip

Do you also have other fault codes?

Do you also have
other fault codes?