P06E4: Control Module Wake-up Circuit Performance

What does P06E4 mean?

Control modules are woken by a dedicated wake-up line or a network wake-up – at ignition on, when a charging cable is plugged in, or on a timer for engine-off diagnostics and battery management. P06E4 means this wake-up signal is implausible: the module wakes too late or not at all, stays awake, or the line state does not match the network status. In practice the code appears mainly on hybrids: FCA fixes it on the Pacifica plug-in hybrid and the Wrangler 4xe with module software, where it remained as a permanent code that blocked emission inspections; GM's hybrid integration module lists it as a fault bundle. No manufacturer publishes thresholds or timing.

The code tells you which monitor failed, not which part is broken. Test before replacing parts.

Symptoms

• Check engine light
• Permanent code blocks emission inspection
• Possibly battery drain (module stays awake)

Common causes

• High Module software (false setting, permanent code does not clear)
• Medium Wake-up line or connector open or shorted
• Medium Weak 12 V battery, voltage dips at wake-up
• Low Engine or hybrid control module faulty

Likelihood is a general estimate across vehicles; your make and model may differ.