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The FICM gets its signal from the PCM. As you describe it, it sounds like your anti-theft system has been activated and is currently not allowing the engine to start.
The Passlock(tm) system is designed to prevent vehicle theft by disabling the engine unless a mechanical key is used to correctly engage and rotate the Passlock(tm) lock cylinder. System components include ignition switch, Passlock(tm) lock cylinder, Passlock(tm) sensor, Passlock(tm) module and Powertrain Control Module (PCM).
Do you have a second passlock key that you can try? If not, you would need a scan tool capable of communicating with the various modules in the truck to see what's happening.
Thought you might need this:
30-MINUTE LEARN PROCEDURE1. Turn ON the ignition, with the engine OFF.2. Attempt to start the engine, then release the key to ON, vehicle will not start.3. Observe the SECURITY telltale. After approximately 10 minutes, the telltale will turn OFF.4. Turn OFF the ignition, and wait 5 seconds.5. Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes. The vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.6. Start the engine. The vehicle has now learned the Passlock Sensor Data Code and/or password.IMPORTANT: The vehicle learns the Passlock Sensor Data Code and/or password ***** the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.7. With a scan tool, clear any DTCs if needed. History DTCs will self clear after 100 ignition cycles.
If, as you say, there's no passlock on that truck, then there's no Security telltale nor, if the truck has the optional Message Center, the word SECURITY will be displayed.
In any case, I can't see where anything you've done would cause the engine not to start. So, the only way to find whether or not there is communication between the PCM and the FICM or if there is something else preventing the signal from getting through is with the help of a Tech-II or equivalent scan tool.
I'm sorry if I didn't explain it better: the computers in your truck communicate with one another through a serial data bus; probing these bus wires with anything but a scope won't show us much - even with a scope, all we'd see is a serial data signal if one was there. We still wouldn't know what that serial data meant.
What we need is a dealer-level scan tool such as the Tech-II that can communicate with all the modules in the truck, read serial data and interpret it for us. It can also tell us if any of those modules is preventing others from getting the signals they need to go to work. I wish the carmakers had made it easier for us to work on these vehicles, but they just want to push us back to their dealers where they can charge us whatever they want
I'm afraid I would have to agree with you, since you don't seem to have access to the tools you would need to use in order to follow my intructions. But wait, another expert on the site might know what to do. I'll opt out so others may try. Please don't reply until another expert responds or the site will cycle the request back to me.
Welcome, I'm Chris (aka Moose). Experts aren't employees / agents of Just Answer. We are independent service providers using the Site to sell their Expert knowledge to Customers. I strive to provide EXCELLENT 5 STAR service, let me know what's needed from me so your pleased.
So your getting no trouble codes?
Are the cam and crank sensors getting an accurate signal back to the PCM?
Using your scan tool and cranking the engine are you getting a CMP and CKP signal that is consistent and just about identical?
Your scan tool may not be sophisticated enough. Do you have the ability to try another. We need to confirm the computer is getting these signals to figure out why your getting no injector signal.
low reference pin 21 YE/BK
CKP signal pin 12 LB/WH
12 volt reference pin 2 LG
CMP signal pin 73 BR/WH
low reference pin 61 PK/BK
12 volt reference pin 39 RD this is the only one in connector 2 at the ECM
Your correct if the FICM is not getting a signal, it will not pulse the injectors.
Hello again Chris here,
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A fuel issue that may be causing a misfire could cause a incorrect CMP and CKP code to store from the engine speed abruptly changing. There is a priming step, not a bleeding step.