Hello, i had a this code pop up on freightliner cascadia and i just cant figire it out. from the research ive done it goes to the backup alarm on the driver side firewall. i shorted the wire and a new code popped up: SPN 925 FMI 4. ive replaced the alarm itself and its still the same code as FM5. we dont have troubleshooting or diagrams im able to get at my shop as they refuse to get it
A quick google search turned up this jewel here. It could be as simple as a little corrosion needing to be cleaned off the plug. A 225.3 SPN 925/FMI 5 – GHG14 Vehicle Power Shutdown that Indicates an Open in the Pin 17 Circuit of the Common Powertrain Controller #3 Connector For wiring schematic information refer to Original Equipment Manufacturer (OEM) literature. Note : The Common Powertrain Controller (CPC) digital outputs have the same SPN as some Motor Control Module (MCM) faults. DiagnosticLink Standard makes the distinction between the MCM and CPC when diagnosing a fault
so i need to follow the #17 pin wire and see where it splits or leads cause the pin itself isnt corroded or messed up
That's what I would do. If you're comfortable anyway. Not saying it will be the issue just that it could be.
idk, i tested continuity and its good, i checked both resistance and everything else is good. unless its broken somewhere and holding on by one gut wire or maybe it has something to do with a subbus switch cause theres a code for it too. i appreciate the help tho
