The relay isn't the issue. You have to BYPASS it to allow you to troubleshoot the circuit.
All cars have a means of turning the fuel pump off when the engine stops rotating. Chrysler calls theirs the automatic shutdown, (ASD) relay. The Engine Computer turns that relay on for one second when you turn on the ignition switch, then again during engine rotation, (cranking or running). The computer knows to do that by the signals it receives from the crankshaft position sensor and the camshaft position sensor. Those signals also synchronize the firing of the injectors and ignition coil(s).
The ASD relay sends current to the ignition coils, injectors, oxygen sensor heaters, alternator field, and the fuel pump or pump relay. This is where way too many people get hung up on the first thing they find missing. For some reason that is usually the fuel pump, possibly because more observant owners know they should hear the hum of the pump for that first one second, and they notice they aren't hearing it now. Actually, a loss of spark is responsible for about one percent of cranks / no-starts, and a dead fuel pump is responsible for perhaps another four percent. That leaves 95 percent of no-starts caused by a loss of both fuel and spark. That's why when you find one of them missing, it's important to check for the other one.
If you bypass the fuel pump relay with a piece of wire, or pop the cover off and hold it turned on with a rubber band, you should hear the fuel pump running. The ignition switch doesn't have to be on for that. This is a quick test to tell if that circuit is okay. If the pump runs, there's no need to troubleshoot that circuit.
Thursday, July 2nd, 2015 AT 5:27 PM