Originally Posted by Staterules9

'05 Limited Convertible, when I went to start my car this morning the engine turned over for 5 seconds or so but would not fire and crank. I normally wait for the fuel pump noise to stop before I start cranking, on my first try I thought I just didn't hear it start up. But after the failure to crank I tried again and it was definitely missing.

I pulled the RCM and looked at the solder joints thinking this was a mystery no start. However, they look pretty good, have a negligible resistance from the backside to the front side. (Low resistance? What did your meter say? A resistance of even 1 ohm is too much. Appearance is not a measurement of resistance.) I then plugged the RCM back in and had someone turn the key to the on position. The relays snapped closed to complete the circuit, but there was no noise for the fuel pump (there was a fan noise that started up). (If the engine cooling fan is spinning up to high speed, you have a case of the ECM not powering up at the same time the Fan Module IS powering up - this indicates that the output of the engine control relay is not making it to the ECM. Most commonly, this is fractured solder on the RCM somewhere, or bad contacts on the Engine Control relay itself.) I had them then try to crank and once again it just turned over for a few seconds before shutting down.

I've read on here that the fuel system needs input from the crank shaft position sensor and cam shaft position sensor. If either of those were bad I would not expect the relay to snap into the closed position. CLose, but not quite - The fuel relay will still close, there IS no input from the cam/crank sensors until the starter engages - after a few seconds, if the engine is not spinning the fuel pump relay DOES cut out. Is that the correct way to think about it? Right now I'm thinking I've got a bad fuel pump. How can I verify before purchasing and replacing? Measure voltage at teh connector on the RCM that goes to the Fuel pump when the relay is closed.

Prior replacements as follows:
Camshaft PS - October '18
Crankshaft PS - August '15
SKREEM - October '18