Conditions for Running the DTC

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0667

No other ECM or TCM DTCs are set.
Engine speed is 400 RPM or greater for 5 seconds.
Ignition voltage is 8.6 volts or greater.
Brake torque is not active.
Engine torque signal is valid.
Throttle position signal is valid.

DTC P0668

Engine speed is 400 RPM or greater for 5 seconds.
Ignition voltage is 8.6 volts or greater.

DTC P0669

Engine speed is 400 RPM or greater for 5 seconds.
Ignition voltage is 8.6 volts or greater.