> Having issue with power supply regarding wire running from the crankshaft > sensor. Running -TO- the crankshaft sensor. 8 volt supply, pin 44 of the PCM, supplies 8 volts to the crankshaft sensor, camshaft sensor and flex fuel sensor if equipped. Any of these can short out and kill the supply voltage to the other sensors making them inop.
> When problem happens, the van will crank but not start. On a scope, > when it happens it does not show any codes, but indicates crank 0, cam 0. On a scan tool?
> The crankshaft sensor was replaced 3 weeks ago after the problem first > started (with a non-Chrysler product). The mechanic at that time still had [quoted text clipped - 12 lines] > says it may in fact be something else. What are your thoughts on this > matter. Thanks for your help. I'd unplug all sensors powered by the 8 volt supply and test for 8 volts being present. If so, one of those sensors may be shorting and drawing the 8 volt supply down. If you don't have 8 volts at the sensors when they are unplugged, look for an open circuit in the 8 volt supply wire, if you don't find an open circuit, test for 8 volts directly at pin #44 at the PCM.
Also check for a broken flywheel, if the cam and crank sensors go out of synch because of a broken (shifted) flywheel, you'll get the exact symptoms you describe.
|