[JonH1]

04 Crewcab 6.0 goes in for warranty work and they pull the cab to redo head gaskets and an egr cooler. Upon reassembly, they get a no start condition and change out the ignition module - strange as the truck ran fine other than blowing coolant through the exhaust.

Pick up truck and the next day notice the sound coming through the radio which is common to a leaky or poor ground. Any insight on which wires might be the likely culprit during cab removal?

I'd hate to take it back in and lose it for another week when it might be something I can fix in a few minutes.

Thanks, Jon

 

[logan21sv]

Passenger side cab to frame rail there is a ground strap that can be over looked, or the passenger side neg. bat. cable goes from Bat. to the frame and then to the block.

those are the first two I would check. hope this helps

 

[rebuilder]

Yeah I had gaskets done 2 months ago and my ficm mysteriously decides not to work one day?

 

[JonH1]

[ QUOTE ]
Passenger side cab to frame rail there is a ground strap that can be over looked, or the passenger side neg. bat. cable goes from Bat. to the frame and then to the block.

those are the first two I would check. hope this helps

[/ QUOTE ]

Dangit - both of those are intact.

 

[GrampyJim]

That is called $hit happens... our shop has replaced the odd FICM so it's not like they can't ever fail....

It'd be like saying "I had my oil changed two months ago and then my tire mysteriously went flat...".

Just because I'm paranoid doesn't mean I'm not being followed....

 

[GrampyJim]

There is an oft forgotten ground strap fom the rear of the right cylinder head to the cowl above the heater box.... This is a fairly long strap that snakes around near the MAP sensor...

 

[rebuilder]

When my cab was off I saw my ground strap was torn from cab to frame under the passenger feet area, I just assumed they would fix that. I picked my truck up today and decided to look under there and sure enough it is still torn /ubbthreads/images/graemlins/depressed.gif I sure hope its not the cause of a burnt out ficm at my expense, I did get mt axx under there and rig it up myself.

 

[ta152h0]

When my son crashed his car, he had grounding problems also and I just made a couple heavy wire groundstraps and went from alternator bracket to the frame in two different spots. Problem solved, the computer was happy.

 

[JonH1]

[ QUOTE ]
There is an oft forgotten ground strap fom the rear of the right cylinder head to the cowl above the heater box.... This is a fairly long strap that snakes around near the MAP sensor...

[/ QUOTE ]

dangit, that one is intact as well....

 

[JonH1]

now that i look, the rear tag light circuit is acting up as well. lamps are good, plugs are plugged in, fuse is fine........ light no workie

 

[ford_doctor]

[ QUOTE ]
There is an oft forgotten ground strap from the rear of the right cylinder head to the cowl above the heater box.... This is a fairly long strap that snakes around near the MAP sensor...

[/ QUOTE ]

Jim, do you think the ground at the left rear intake manifold bolt for the injector harness shielding could be off or loose? We know how troublesome those shielded harnesses can be! /ubbthreads/images/graemlins/wink.gif

 

[ta152h0]

Those high resistance shorts are a PIA to find. That is why I just make new ground straps and install them.

 

[GrampyJim]

Rereading the original concern, it might well be but it's one I forget about... not because it gets forgotten to get connected but because, too many times, the nut is tighter than the stud and everything tries to come out at the same time. That and it draws blood if I don't deal with it come IPR time...

Along with that, we see repeated instances of shoddy work -like what rebuilder2 saw (and how many dozen rear main seals we've read about)- and I can only shake my head.

Sadly, it isn't a problem just in the automotive trades but we see this kind of cavalier crap going on everywhere...

"I have seen the enemy... and he is us..." Pogo Possum remarking on society in general...

 

[ta152h0]

I looked in the wiring diagram for mine and there is a lot of grounds. Very much reminiscent of my "working on airplanes" days, computer controlled machinery likes electrical return paths ( grounds )

 

[JonH1]

when they pull the cab, do the seats come out? If so, there's a chance they didn't install the aftermarket amplifier grounds that were under the rear seat. As it's raining now, I'll check those tomorrow and ensure they are making good contact.

That would not explain the rear tag lights going freaky on me though. While taking it back in for the whiney radio would likely be covered since it wasn't happening before they yanked the cab, I can't say for sure if the tag lights were working before they yanked the cab. I didn't notice them until I started looking at it and would rather not drop another Benjamin on getting tag lights fixed.

Can anyone tell me which color wires or which pin I can check at an upstream plug in order to determine where (and if) power or ground is failing for the tag lights? The lights themselves are fed by two wires and do not have a grounding contact where they plug into the bumper.

Thanks, Jon