P068A High Generic / SAE

P068A: Engine Control Module Power Relay De-Energized Performance — Too Early

Powertrain Computer Output Circuits and Control Module Emissions related

What to do

Fix this one before anything else it is stored alongside. The engine module keeps working for a few seconds after you switch off, saving what it has learned — and this fault means its power is being cut before it finishes. Anything else that gets repaired first can simply be corrupted again the next time you switch off.

Mention if the car has developed a rough idle, or if faults keep coming back after being cleared. Those are the everyday signs of settings being lost at shutdown, and they fit this exactly.

Mention any damp in the fuse box area, or a blocked scuttle drain below the windscreen. Water reaching the relay is a common cause.

The repair is often just a relay or a corroded socket, which is inexpensive relative to what it protects.

What this code means

The engine module's main power relay is dropping out before the module has finished shutting down.

This is one of the most consequential codes in the block, and its importance is entirely invisible from the driver's seat.

A modern engine module does not switch off when the ignition does. It holds its own power on through the main relay and carries out a shutdown routine: writing learned fuel trims, throttle and idle adaptations, and fault history into non-volatile memory, running any cooling fan run-on, and parking actuators in known positions. Only when that is finished does it release the relay.

This code says the power went away first.

The damage is cumulative and it lands somewhere else. Every interrupted shutdown risks corrupting a memory write in progress — which is why an EEPROM error is so often stored alongside, and why adaptations mysteriously reset, idle goes rough, and faults reappear after being cleared.

So if this code is present with a memory error, fix this one. Replacing or reprogramming a module while the relay still cuts power early simply corrupts the new one too.

The causes are ordinary and cheap by comparison: worn relay contacts, a corroded relay socket or fuse box terminal, a poor earth on the relay's coil circuit, or water in the fuse box — which is a frequent finding on vehicles with a blocked scuttle drain.

Likely causes

Start here

Less common

Poor sensor ground connection · moderate
Low system voltage · easy

Symptoms

Components involved

Information, not instruction

CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.

Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.

Community experience

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The car — make, model, year and engine. The same fault behaves differently on each.
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What actually fixed it — or that nothing did, which is worth knowing too.