DTC B2470, Daytime Running Lights Fault: Notes

WARNING: This page is about a different car, the 1997 Cadillac Seville, 1997 Cadillac Eldorado, and 1997 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

Daytime Running Lights (DRL) are commanded on and off by PZM through DRL relay. DRL are activated when ignition switch is in RUN or START position, twilight sentinel is not active, headlights and foglights are off, and transmission is not in Park. When DRL relay is energized, high beams are placed in a series circuit which provides lower illumination for DRL.

A short to ground will be tested when ignition switch is in ON position, DRL are inactive, and IPC verifies vehicle is equipped with DRL. A short to voltage will be tested when ignition switch is in OFF position, DRL are active, and IPC verifies vehicle is equipped with DRL.

DTC B2470 will set when commanded state of DRL does not match feedback state. When DTC B2470 is set, PZM will continue to command state requested until it is achieved or changes. DTC B2470 will clear when commanded state matches feedback state for 2 consecutive monitoring cycles.