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roybelding, Shop Foreman Freightliner trucks
Category: Medium and Heavy Trucks
Satisfied Customers: 5859
Experience:  Shop Froeman for Freightliner Trucks
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2011 Freightliner, ISB spn 3251 FMI 6, cummins insite will

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2011 Freightliner, ISB spn 3251 FMI 6, cummins insite will not allow regen because ecm detects condition. Replaced sensor, repaired burned wiring, cleaned dpf, reset maintenance.

good afternoon my name is ***** ***** I will assist

did the code go inactive after the repair???

did you try clearing the code???

it will not re gen if the condition still exists


Customer: replied 1 year ago.
Code will not go inactive. Clearing goes away for 30 seconds. Comes back active.

then it is still active. the sensor was not the issue. how did you determine the sensor had failed???

what reading did the data monitor give you while monitoring the sensor voltage>>>


Customer: replied 1 year ago.
we changed sensor directly because of code. sensor voltage is 0.46, changes with throttle. unsure what normal operating range is. Has 5v at signal in, but 0 at 5v return.

80% of the time, the wiring is the issue as it is here. the harness is the issue. you either need to trace the harness for damage or wear through especially at the trans or replace the acm harness. have done many acm harness for this issue.


plase dont forget to rate me as it is the only way I get paid for my efforts


Customer: replied 1 year ago.
there was a connector on top of trans that was burned up, repaired all 13 wires, and no change. would it be higher up? so far, from the DOC up the right side frame, across trans tail housing, and to left side frame all ok.

top of left front frame rail is common as well.


Customer: replied 1 year ago.
all looms in tact. any pin tests that can be done at ecm? anything else i should be looking for?

you can disconnect the acm and the harness at the other end and do an ohm check on each wire but you will be confirming what we already know. you have a bad harness. I would just replace the harness. we used to stock them. they are not that expensive and take about 2 1/2 hours to replace


how are you making out???

Customer: replied 1 year ago.
well, put the harness on. no change, code did not go inactive. have a 1921, 3261, and 3651 active. History behind this truck, DEF pump new, line heater #2 new, aftertreatment diff pressure sensor new, now acm harness new.

ok, engine serial number???

Customer: replied 1 year ago.
ESN 73328002
Customer: replied 1 year ago.

have you cleared the code and attempted a re gen????


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