Common Ground Glitch?

[ChucktownJohn]

Two days ago, I started my truck and it chimed at me with the well known "abs and brake" lights illuminated. I thought, oh crap, there goes my brake control module or something like that. But then I noticed my speedo was not working and when I finally parked, I went to roll up the windows and those weren't working either. I figured it was a fuse or something, so I cut it off and was going to look at the fuses. For the heck of it, I turned the key back to the on position... No lights, no chime, and the windows worked again.

I looked at the fuse panel and didn't noticed any common fuses between the speedo, abs and windows.

So could this be a common ground issue?

Everything has been working fine since the first hiccup, but I want to make sure it does not happen again.

Cheers!

[VanillaGorilla]

I had a gremlin in mine forever... The speedo would drop to zero, the wipers would quit (usually when it was raining) and the overhead and cruise would quit. I replaced all kinds of stuff including the PDC and the FCM, a lot of $$$ even though I did the work myself. It turned out to be a ground. I finally gave up and took it to the dealership and they fixed it within an hour, although they charged me around $120 to tighten a nut. I looked everywhere for the grounds but just couldn't find the bad one.

[ChucktownJohn]

Originally Posted by VanillaGorilla

I had a gremlin in mine forever... The speedo would drop to zero, the wipers would quit (usually when it was raining) and the overhead and cruise would quit. I replaced all kinds of stuff including the PDC and the FCM, a lot of $$$ even though I did the work myself. It turned out to be a ground. I finally gave up and took it to the dealership and they fixed it within an hour, although they charged me around $120 to tighten a nut. I looked everywhere for the grounds but just couldn't find the bad one.

That's pushing me closer to believing it's a ground. The stealership tell you where the ground was? I will look around tomorrow, have to change the oil anyway.

[VanillaGorilla]

Originally Posted by ChucktownJohn

That's pushing me closer to believing it's a ground. The stealership tell you where the ground was? I will look around tomorrow, have to change the oil anyway.

No, only that the nut was held on by about 1/2 a thread.... You might google it though.

[mkwelds]

Ur important grounds are the two from batteries to block. One from ecm to block one from wiring harness to block same location as he ecm ground. Back of block to cab. There are various little ones under the dash you can check but I don't see one of them throwing out all of that.

[ChucktownJohn]

Thanks MK. I will try to trace these today. Sounds like maybe the ECM/wiring harness to block, would be my best bet. I really don't want to start digging under the dash. I have another car (85 Benz 300td) I am messing with stuff behind/under the dash. What a rat's nest under there!

I am going to back each one off, then tighten them back up and spray 'em down with some Corrosion X.

[10sc]

Originally Posted by mkwelds

Ur important grounds are the two from batteries to block. One from ecm to block one from wiring harness to block same location as he ecm ground. Back of block to cab. There are various little ones under the dash you can check but I don't see one of them throwing out all of that.

I'm having pretty much the same problems with a few more added. Mine are:
Horns - maybe nothing, maybe only one of the two.
Cruise - quits after 2 minutes or 10 miles (about the most I've ever got).
Wipers - while on slow, it will sometimes work like it's on full speed.
Wiper washer - has never worked (since I bought this 2 weeks ago)
Locks - will sometimes not lock/unlock one of the doors.
Windows - one will sometimes only work from the drivers door or driver's window will not work.
Door ajar alarm - will sometimes sound/alert once or twice then quit.

Battery grounds have been "reset". What other ground might I check and where would it be?

I have:
2004 3500
w/o duel wheels
4wd
Quad cab full bed
3" lift kit
Looks like it once had amps under both of the front seats.

Any help would be appreciated. I have to take a 1500 mile trip in about a month and would sure like to have the cruise working.

Thanks

[10sc]

[QUOTE=10sc;5565077]I'm having pretty much the same problems with a few more added. Mine are:
Horns - maybe nothing, maybe only one of the two.
Cruise - quits after 2 minutes or 10 miles (about the most I've ever got).
Wipers - while on slow, it will sometimes work like it's on full speed.
Wiper washer - has never worked (since I bought this 2 weeks ago)
Locks - will sometimes not lock/unlock one of the doors.
Windows - one will sometimes only work from the drivers door or driver's window will not work.
Door ajar alarm - will sometimes sound/alert once or twice then quit.

Battery grounds have been "reset". What other ground might I check and where would it be? I bought a Chilton book for this truck but it's pretty worthless as it doesn't tell me where much is located.

I have:
2004 3500
w/o duel wheels
4wd
Quad cab full bed
3" lift kit
Looks like it once had amps under both of the front seats.

Any help would be appreciated. I have to take a 1500 mile trip in about a month and would sure like to have the cruise working.

Thanks

[CarolinaRam]

I stopped at my local dealership just to air up a tire when I was coming by. The diesel tech came to the truck and said that he wanted to check something on mine. He looked at the ground coming off the battery to the ECM. There is 4 wires there, 3 go to the computers and the final to a oxygen sensor. These 4 wires are just crimped into place there and he said that they build up heat and cause the computer to throw codes and act up. He also said that somehow it affects the fuel mileage on the truck, where the 4th gen doesn't get the fuel mileage the 6.7 did in 3rd gens.

Needless to say, he will be soldering mine Monday morning. He said that I could do it if I wanted but he would do it at no charge if I would just let him know if it changed the fuel mileage any at all.

Anyway might give you something to look at.

[ChucktownJohn]

Wow, a tech who actually cares about what he does. That's rare nowadays.

To 10sc: after I retightened all the grounds I could find, I sprayed them down with corrosion x. Everything has been fine until just these past couple weeks. I've had a glitch with the wipers and my passenger window wouldn't go up(not at the same time). I probably need to go back and do this again. There are lots of grounds along the front quarter panels and firewall.

About your cruise... Mine has never worked, well it just shuts off after a few miles. I have read on this forum that there is a vacuum motor that controls the cruise. It eventually leaks out enough that the cruise shuts off. You may want to investigate this, but I think that the part is pricey. I've never cared enough for cruise to fix it.
Good luck. Let us know how it goes.

[10sc]

Well I finally found the time to take the truck to the dealership for a check. They said the systems I listed didn't have a common ground. They took it for a test drive and everything worked fine for them (always does it seems) except the washer pump which they said is dead.

Basically, I'm going to have to live with this until it gets to the point that it's happening more often and I can get it to fail for the mechanic.

[jmercer]

I had an issue a while back where I lost all backlighting on my gauges, speedo didn't work, and ABS and Brake light were on.

I discovered a shorted out wire that was causing the problem. Check the wire that runs through the arm to your sun visor. There is a small wire in there that feeds the vanity lights for the mirror.

Just un-do the 3 screws that hold the sun visor to the roof and pull it down a bit. The wire in mine was mashed flat and blew a fuse. Yours might be rubbing on the metal in there causing intermittent problems. Just another thing to check out. Doesn't take any time to have a look.