Conditions for Setting the DTC
WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
The 4th clutch is commanded OFF and the hybrid powertrain control module detects the clutch 4 slip speed is less than 80 RPM for 3 seconds.