04 - 6.0 ABS light on, speedo off, ac kills engine, starts fine
OK, here one for all you mechanical expert, of which I used to think I was one.
I took the 04 for a cruise at lunch, a few miles down the road I notice the ABS light is on, also notice the Prodigy controller flashing an error. Pull over, turn the engine off, restart, all seems normal. Drive another mile or so, ABS comes back on, speedometer and all Dash gauges drop out. Pull over again into a gas station, check to make sure serpetine belt is on - OK, everything normal under the hood. As I was sitting there idling, I notice if I turn all electrical items off (ie AC, Radio, light, etc) ABS light goes off and dash responds. As soon as I turn on AC or power windows, ABS light goes on and with AC - dash drops out. With the exception of the AC symptom, you would think VSS - right! But now with the AC or other higher current draw, I am kind of leaning towards a bad battery (replaced last year) or a bad alternator.
But get this, when I got back to work, I would turn on AC and the engine would die. Now you think definitely bad battery or alternator. Except that everytime the engine dies, it cranks normal and starts up again. My experiences are that if the battery is so low that drawing high current kills the engine, the same batteries are not going to spin the engine over at a normal rate, especially not a diesel engine.
Am I missing some thing here?? Does the engine use the second battery to start and the primary to run??
Has anyone seen or heard or this before??
Last edited by desrtracr; 06-16-2008 at 04:23 PM.