Re: 1992 377 Pete won't fire up Your symptoms are classic with losing ecm power or a failing ecm which you allready replaced. Running new powers and gro[more ...] Posted by Goodysnap 26 May : 02:23
Re: 1992 377 Pete won't fire up Goodysnap,Thanks for the reply. Do you suggest for us to just run new power lines to the ECM? Posted by pharo 25 May : 20:09
Re: 1992 377 Pete won't fire up I would be load testing the powers and grounds to the ecm on the oem side. It is likely that you have excessive voltage [more ...] Posted by Goodysnap 25 May : 14:53
1992 377 Pete won't fire up Hello everyone,I appreciate any help with this one. I have a 1992 Peterbilt dump truck model 377 with a Detroit S 60 12.[more ...] Posted by pharo 24 May : 20:05
New Member LTL TL Trailer Parts Hello TMT members I work for a large company in one of its many parts supply shops. I order and ship parts to the compan[more ...] Posted by go7uknowhatimean 22 May : 15:15
08 6.4 powerstroke HI I have an 08 f350 powerstroke. Im thinking it's tuned it has a 4" straight pipe and when I try to scan the truck it [more ...] Posted by PWRJOKE 14 May : 17:52
We have a 2010 Prostar that has problems with the airflow coming out the vents while going down the highway. He will be going down the highway and the airflow will reduce to almost nothing. When the driver comes to a stop, it will start back up again. We have verified function of all of the actuators and ductwork.The blower motor also doesn't reduce speed. Anybody have any tips/experience with this problem? VIN 3HSCUAPR4AN272126
No experience with that exact problem on that exact truck, but I have few suggestion or questions to ask yourself. 1. Could the module on the blower motor be going out when it gets hot? 2. You said heater, but could the unit also be in defrost mode and the evaporator is freezing up from the A/C clutch staying on due to faulty inlet and outlet temperature readings. You will need to use dimaond logic builder to look at those 2 temperatures. If the evaporator freezes it will restrict air flow. In the winter time there is a larger delta between outside ambient temperature to condensor temperature, so the system can pull heat out of the system much quicker going down the highway versus when the unit stops.
Freightliners use to have that problem all the time with the Blend air system, winter or summer. Driver complaint no air flow. The HVAC relay would stick close and the system could not cycle the A/C clutch to prevent freeze up. You could indentify this by turning on the ignition switch and the compressor clutch would be engaged. On a blend air system the clutch should not be enaged with just key on, a parameter that needs to be seen by the AC module is engine rpm above 500 rpm for 15 seconds.
I belive you can do this same check on a ProStar, the A/C clutch output is direct from the Body Controller to the clutch and it does need to see engine rpm for engagement. Hope this helps with some of the troubleshooting proccess.
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