P06B6

What it means

P06B6 is a generic code meaning the engine control module has found a performance fault in the internal processor that handles the signal from knock (combustion vibration) sensor bank 1. The module runs self-checks on this circuitry and the result did not match what it expected. Because the fault is inside the module itself, the knock signal can no longer be trusted for spark control.

Symptoms

• Engine warning light on
• Reduced power or flat feeling under load
• Poorer fuel economy
• Rough running or hesitation under acceleration
• Engine may run in a limp-home or reduced-timing mode
• Other knock sensor or internal control module codes stored alongside

Possible causes

• Internal fault in the engine control module's knock processing circuitrylikely
• Low or unstable supply voltage or poor battery condition upsetting the module's self-testspossible
• Poor or corroded earth or power supply connections to the engine control modulepossible
• Wiring or connector fault on the knock sensor circuit that the module reads as a processor performance problempossible
• Outdated or faulty control module software, where the manufacturer has issued a correction for this faultrare
• Water ingress or physical damage to the control modulerare

How to diagnose

1. Read all stored and pending codes and note the freeze frame data, including engine load, speed and battery voltage when the code set
2. Check the battery state of charge and charging voltage, and correct any weakness before going further
3. Inspect the knock sensor wiring and connectors for chafing, oil contamination, corrosion and a loose fit
4. Inspect the engine control module connectors, power supplies and earths for corrosion, looseness or damage, and check for water ingress
5. Look for other knock sensor, sensor supply or internal module codes, and deal with those first as they may point to the root cause
6. Clear the code and road test, then recheck whether it returns and under what conditions
7. Check for any manufacturer software updates or technical bulletins for the specific model and engine
8. If the fault persists with sound wiring and power, test or substitute the control module following the manufacturer's procedure

How to fix

• Repair or replace damaged knock sensor wiring or connectors
• Restore good power and earth connections to the control module
• Replace or recharge a weak battery and repair any charging system fault
• Update the control module software where an outdated calibration is a known cause for this model
• Repair or replace the engine control module, with correct coding or programming as the manufacturer requires

Can I keep driving?

Nearby codes

• P06B5GenericSensor Power Supply B Circuit High
• P06B7GenericInternal Control Module Knock/Combustion Vibration Sensor Processor 2 Performance