Watchdog Check
WARNING: This page is about a different car, the 2004 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
The external watchdog circuit is coupled to the valve power relay. If the external signal is not active, the valve power relay cannot be operated. The watchdog circuit is checked by disabling the external watchdog signal. The relay command is issued with the watchdog signal turned off, and if the relay does turn on, then the watchdog circuit is not functioning properly, and a ignition-on DTC (fault) is issued.