Ram B1500, B2500, B3500, 1999-2003

Circuit Protection


On vehicles equipped with air bags, disconnect the battery negative cable(s) and wait for two minutes before doing any work on the PDC and junction block. This will eliminate possibility of an accidental deployment.

The vehicle's electrical components are protected with a large number of fuses connected at critical junctions of the wiring system.

"Maxi fuses", located in the Power Distribution Center (PDC), have high amperage ratings and replace the "fusible links" of previous years.

"Mini fuses", with lower amperage ratings, are located in the PDC and on the junction block (or fuse panel) located on the left side of the dash panel.

Both the PDC and the junction block provide location for relays as well.

The junction block at the left end of the instrument panel can accommodate up to two circuit breakers. These are used to protect power windows and power seats, if fitted.

Circuit breakers will interrupt the circuit in the event of a short circuit or an overload condition caused by an obstruction to free movement of the window or seat, which would tend to overheat the motor.

The circuit breakers are automatically reset when the failure corrects itself, however, that does not mean that the problem is repaired. If a circuit has a motor that is going bad, the resistance will be high and eventually the circuit breaker trips and power is shut off to the circuit. When the circuit cools down, and the circuit breaker works again, so will the windows or seats, however the breaker will trip again when the resistance builds.

Circuits that might be needed in case of an emergency or to operate the vehicle (like the power door locks) have circuit breakers instead of fuses.