The engine won't start. I have changed the cam sensor. I got a code Eng SID 251 80 power supply low voltage **inactive** on the silver leaf. I get 1 volt drop at the fuel shut off. I will change the fuel filters tomorrow. Any ideas?
Best I can tell 251 is related to the real time clock in the ECM. Probably an internal battery failure. Call Cummins.
"This fault indicates that the real-time clock in the ECM lost power. Possible causes for this fault are weak or damaged real-time clock battery, damaged wiring or connectors between the battery and ECM, Or the vehicle battery power to the ECM is lost."
Low start battery voltage?
I found something in Cummins Quick Service that a connection may be lost. I was
working in that area before it wouldn't start. Thanks Roger any ideas will help.
I dont think the clock for the ecm would not let the engine start. More likely a before and after diagnosis. Was the engine starting before you changed the sensor? And then not starting after you changed it.
The engine wouldn't start before I change the sensor. I changed it as one part of
the sensor had no continuity.
Sounds like you have resistance in a connector. I'd start with the ECM connections. Hate those issues. They can be a real pain to find
Scott
Had a look this afternoon and found a wire out of the fuse holder. It was totally corroded.
Put a jumper between the two wires and the engine fired right up. Will go out and buy new
fuse holders tomorrow and change both of them. I love a cheep fix. Roger the code I had disappeared
and there are no codes. Will the Silverleaf give me all the codes. Thanks everyone for the input.
Glad you found it watch those new fuse holders.
On my old prerunner I sold last year we were at King of the Hammers in California and the car just quite. Check all the fuses. Replaced a 400$ MSD unit same problem. The #10 gauge inline fuse holder was the cause of my problems. Wasn't holding fuse tight. Still have a 1 minute total time MSD ignition unit. Need to put on eBay and sell come to think of it :headwall:
Scott
While the real time diagnostic message window clears itself, the codes remain in the diagnostics log.
On the Main Menu at the top of the window click on the Diagnostics menu item to bring up the Recent Diagnostics Events box. This box will show any problems that have been detected since VMSpc has been electrically connected to the engine and transmission. Click on the View History button to show past items since VMSpc was installed and running.
Each line of text shows a fault event. The first column shows the source (Engine, Transmission, or ABS Brakes). The next three columns are used by mechanics to find information in their service manuals. The main body is the plain-language description which indicates the component that is irregular or malfunctioning and the type of that malfunction. Finally, the date and time of the first occurrence is given.
Most of these are a bit cryptic and may be hard to interpret. But they are clues to help track down problems. If this case a bad fuse holder or fuse showed up as a power issue in the ECM which as it said in the interpretation might be a bad wire or connection.
I was getting a "Low Potential at injector #6", lots of them. It took some time but tracked it back to an issue with my alternator wiring. Changed alternators, codes went away.
Here is what it looked like and it finished.
Put some dielectric grease in the fuse holders, enough so that the blades of the fuses and the blade holders are well coated. Keeps water and corrosion out and keeps you going.