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Category: Heavy Equipment
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Experience:  16 Years working on Cummins Diesel engines,
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I have a cummins isx in my international 9400i and Im getting

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I have a cummins isx in my international 9400i and I'm getting a fault cod of 128f02 Sid 251_A. I was hoping you could tell me what it is. Thank you much.
Hello and welcome to Just Answer! I would be more than happy to assist you today.what is the engine serial number
Customer: replied 3 years ago.
E.s.n is 79069041
Also code 136f05 sid018_a popped up


MID 136 f05 sid018 id for the ATC (traction control) has an open circuit, A dealer should be able to repair this fault if it does not clear up on its own. If it is not active than it is an old code.


MID128 f02 Sid 251--


You need to check the grounds and power supply to the ecm. Normally the ecm gets the power direct from the batterys.


This fault is set active if the ECM battery supply voltage drops below 6.2 volts while the keyswitch is in the ON position.

Make sure the ECM unswitched battery supply is coming directly from the battery and not the starter. If unswitched power is coming from the starter, it is possible for the battery voltage to drop low enough during cranking to set this fault active.

This fault can also be caused by resistance in the ECM battery supply (+) or (-) circuits. Resistance in these circuits can cause the voltage level at the ECM input to drop low enough to set Fault Code 434 active


Fault Code: 434
PID: S251
SPN: 627
FMI: 2/2
LAMP: Amber

Power Lost Without Ignition OFF. Supply voltage to the ECM fell below 6.2 volts momentarily, or the ECM was not allowed to power down correctly (retain battery voltage for 30 seconds after key OFF).


Possible no noticeable performance effects or engine dying or hard starting. Fault information, trip information, and maintenance monitor data can be inaccurate.

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