DTC P1658: Fuel Injection Control Module Driver Circuits: Description
WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The Fuel Injection Control Module (FICM) self monitors driver performance and sends this information to the Engine Control Module (ECM) through the CAN system. If a fault is detected in the driver circuits, the FICM will signal the ECM, and DTC P1658 will set. This is an internal circuit fault, and can not be caused by external failures.