Diagnostic Aids

WARNING: This page is about a different car, the 2003 GMC Yukon XL, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

A TFP manual valve position switch malfunction can set DTC P0894.
A mechanical failure of the shift solenoids or TCC PWM solenoid valve can set DTC P0894.
Internal transmission failures can result in a DTC P0894.
Sticking or contaminated shift valves may cause intermittent slipping in D4.
DTC P0894 defaults to an elevated line pressure condition which may result in partial TCC apply. This may produce an idle surge that could stall the engine.