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FIX-IT, Technician
Category: Heavy Equipment
Satisfied Customers: 1184
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Freightliner..MBE 900 and allison tranny..check engine light..voltage

Resolved Question:


I have a 2004 Freightliner w/ MBE 900 and allison tranny in my 18' MAC Tools truck. I have a check engine light which comes up as a #57, Aux PWM Driver #1, voltage low or shorted. Tried clearing the code but it comes back imideately. Anything to worry about? I'm on the road every day. Thanks a bunch

Jim Michaud
Submitted: 6 years ago.
Category: Heavy Equipment
Expert:  FIX-IT replied 6 years ago.
Hi there.i can help you with this..ill need your vin and ill look it up..
Customer: replied 6 years ago.

Thanks for the quick reply. My vin is: 4UZAAPCP34CN01497


While checking under the hood this afternoon, I found the flex strap which holds the radiator fan clutch from turning, ripped in half and tore the wires out of the clutch (clutch rotates free and can't engage the fan). Additional codes which I cleared were:

84 road speed volt above norm.

111 coolant level fault

111 coolant ID#1 data valid

231 fault mode ID#2 data eratic intermitent or incorrect

These codes I cleared but the #57 wouldn't clear





Expert:  FIX-IT replied 6 years ago.
57 pertains to your grid heater,trace the wires back from the heater at the intake and you will come to a mag switch,possibly 2 check the small wires make sure no corrosion and tight the code pertains to those wires,let me know what you find and this time of the year i wouldn't b concerned with it,its to warm for them to be it..
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