DTC B1970, Exterior Light Power Fault: Testing
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.
- Turn ignition switch to OFF position. Remove parking light relay and headlight relay. Disconnect PZM connectors. Using DVOM, check resistance between parking light relay connector terminal A6 (White wire) and ground. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, replace PZM.
- Repair short to ground in White wire between parking light relay and PZM. Reconnect all components. Turn ignition switch to ON position. Turn headlights on. If headlights do not come on, replace PZM. If headlights come on, system is functioning normally.