2005 GMC Sierra Electrical issues

[00_NUTT]

Ok guys I'm looking for some help which in the end will require the dealer to fix it. So I am having some weird electrical problems. Sometimes the radio will not turn off when killing the truck and opening any door. When driving the abs, brake, airbag, battery light and seat belt lights come. Also sometimes the power Windows will not work oh and the radio reboots itself while driving at times. Amp gauge dumps to zero when the battery light is on. When the abs and brake light comes on the ac compressor quits cooling. When all this is going on the truck runs flawless. I have changed the ignition switch and upgraded my grounding from battery and grounded the alternator itself. Also I checked the ground that grounds behind the block since that has been a common problem for others. Truck only as 83,000 miles on it. I have also pulled the cluster apart to make sure nothing was burnt or hot looking plus I had to rebuild the gauges since the stepper motors were locked up. Please shed some light here so I can get my truck back to normal. I think it the bcm but the dealer seems to think ecm when talking with them over the phone. Thanks in advance!!!

[Jsdirt]

Sure seems that way.

[Jsdirt]

Yeah, those old Hondas were awesome. If they built cars with that same level of engineering and quality, they'd run over 700k miles regularly.

 

5 years ago I rebuilt a TRX300FW for my neighbor - he ran the thing for an entire year with little to no oil in it! Thing still ran!! Crank was fine, but piston & camshaft were trashed. When I got the piston out, the skirt was cracked all the way across! Averted a catastrophe right in the nick of time. Kept that piston as a trophy, lol.

 

You're spot on about the state of our Nation today. It's a sad time in history.

 

I really need a Mitchell or Alldata subscription, but they cost quite a bit of cash. Hard for me to justify it, since I do more small engines than cars ... but boy, some days I think it's worth the money trying to troubleshoot these electronic wonders with half a billion wires going all over the place, and no idea what does what. I get lucky alot of the times by just doing visual inspections, and going off intuition. A subscription sure would save me alot of time, though.

 

Here's that Honda piston:

 

[Jsdirt]

You can baby it all you want - it's no help for poor engineering, and low quality components. Just the way they build things today. Plus she's got 11 years under her belt - that doesn't help when the stuff wasn't all that good when it was new. The wire they use today is so thin, and the jacket so flimsy, it's a wonder they even make it to 10 years. I've never seen copper corrode so bad as the stuff built after 1995. You can cut a foot off the wire, strip it again, and the copper will still be black.

 

Definitely something related to the BCM, it sounds like to me. Whether it's the unit itself, or the wiring, is the question. Hopefully you can find some competent techs in a local garage close by to you.

[grampadirt]

Notning to add to solving your problem but only to say ALLDATAdiy really isn't that expensive considering all the information you'll have access to.I subscribe to it for both of our Suburbans and at $17.00(for each) a year it's worth it,at least to me.Not much more than a twelve pack if you look at it that way.So at least consider it.

 

I also subscribe to Mitchell,more in depth info and their wiring diagrams are great.

[iCryWheniGoPoop]

Start at the source...The very first thing I would do is change the battery, just swap it out with a friends or wife's to see if problem persists. An internal short in the plates can produce all kinds of crazy things on this more modern technology.

 

If not fixed, check cables for loose/missing connections, deterioration, possible shorts at places that may be rubbing on nearby metal components, all coming directly from battery. Corrosion under the cable sheathing can be hard to spot but can also cause poor connection producing symptoms that you speak of. You can typically bend your cables right where the protective sheathing ends and see a green powdery buildup, but not always.

 

The reason I'm suggesting this is because some of your symptoms only seem to have the battery and its connections in common so... I suggest a good inspection right where the electrical power originates.

 

Good Luck!

Steve

 

 

Sent from Off Driller Side

[00_NUTT]

Dang JsDirt thank God the skirt didn't come totally off. I have a beautiful 300 with a big 8" lift and stretch that is in pieces for its new make over. If I find the before pic I'll post it up. I hear you on the wires and these pay for subscriptions. I borrowed my buddies matco tool and it pulled some errors but when you search for the resolution it pulls up Google, hahaha. Oh and he pays a monthly subscription for that!!!!!

[00_NUTT]

Also the security lock light comes on and at times I hear a relay under the drivers side dash clicking when the truck is off and the radio still playing with the key removed and the door open.

[Jsdirt]

Yeah, that's what pisses me off about everything today. No matter what you do today, it requires a monthly payment. Seems to all go out faster than it comes in. Can't win!

 

I had Alldata DIY in the past. Saved my ass with that POS '00 Jimmy I had. There were alot of times where I was left hanging though - they saved that info for the professional subscribers. Ended the subscription when I parted out the Jimmy.

 

With all the different makes and models I work on, one subscription wouldn't work - I need something where I can jump from any make, year, and model at will. But, that stuff costs. Like I say ... can't win!

[00_NUTT]

Thanks TDT!! Last night I tore my truck apart. Pulled all the module plugs and checked for corrosion, sprayed with contact cleaner and decreased with a very good dielectric grease. Opened up all wire loom and inspected wires for rubbed jackets, smashed and are severely bent wires. I have down loaded the schematic and everything does originate from the battery but does all go through the fuse box under the hood. So next step I'm gonna pull the under hood fuse box and check under it for any noticeable damage. I'm gonna pull the battery off my tractor and try it and see what's happening. I have put a scope on the battery on it now when the problems are happening and the wave form looks good but you never know.

[00_NUTT]

Yea I hear you. We once was a proud nation that designed and built everything ourselves with great quality. We were doers and not followers. The quality of parts are horrible today but yet they keep making things more and more complicated with inferior parts that they know will fell in order to push us in to something else. I am a fan of the older more reliable and easier to service things but they were built right. I still build and run Honda 300's cause they just don't die and its amazing what they can do. I just called an secured a Honda ACT 70 for my little girl. As old as it is it runs like a top. I work on medical x-ray equipment and the last American made xray company has now moved to China. Putting American workers out of work. When I was doing a lot of work in south Texas I remember seeing numerous auto manufacturer executives hiding their logos on the planes and in the rental car places before they crossed over in Mexico. Sorry about the rant but dang it ticks me off. Again thanks for the help and if I had access to the GM tech site I'm sure I could fix it myself!!!!

[00_NUTT]

Always trying to keep the working man down!!!!!!!

[Jsdirt]

Any competent mechanic can fix that - no need to get fleeced at a dealership. Will cost you 50% less at a minimum to have it repaired at a private garage - preferably someplace that specializes in electronic troubleshooting / drivability problems. ECM's normally don't just fail out of the blue. 99.9% of the time, it's anything but.

 

From here it sounds like you've got a bad BCM, or a shorted power wire to it. Could literally be a hundred different things, so over-the-net troubleshooting is fickle at best.

 

If that has an amp gauge, zero or slightly positive is where it should be. If it's going full negative, then there's a chance it could just be the gauge, or, there is a dead short somewhere. If it's a volt gauge & drops to the single digits, the same things apply.

[00_NUTT]

Thanks for the reply JsDirt. OK so today I was picking up my kids from school and the radio rebooted twice. Also the ac compressor was not on as the ac was blowing hot air. Then as I'm driving home the whole cluster lit up with most all the lights. So I said good. Got home and put a meter on the fuses under the hood and all checked to have power on both sides. I also checked my alltinator and its pumping out 14.8 and the battery light is on and the amperage gauge is at zero. I also had the clicking under the left side dash. This is driving me crazy as I truly baby my truck.