Electrical Gremlins

[jrwca]

Need a little help thinking through the best place to start with some electrical problems.

I have a 2008 Suburban 4WD with the 5.3 that I bought recently.

It had some charging issues when I bought it and I found the battery was weak. Replacing it helped, but I still had intermittent issues. I discovered the battery cables both had high resistance. Replaced those and the charging is solved.

Now I have a few other issues...

The front passenger side door lock doesn't work. It tries but it seems like the actuator is weak or not getting enough power.

The passenger side mirror will fold in, but slowly. It will not open back up.

The passenger rear window will not roll up with the switch in that door. It sometimes rolls down using that switch. It works fine using the switch on driver's door.

I am getting code P0463 (fuel sending unit high voltage signal). The gas gauge fluctuates and it's never right. It sometimes drops to empty and throws the code when it does.

The alternator sometimes whines (not through the speakers, but similar sound). The alternator is brand new.

It all makes me think a bare wire is causing a short or there's a ground issue. And maybe they're not all related. I've crawled around looking at the wiring and haven't noticed anything obvious. I started checking grounds, but haven't found any issues so far.

Any idea where I should start looking? Does all this narrow down likely problem areas?

 

[Big Mama]

How about your other ground cables? It’s interesting that it’s all on the right side. Have you moved another door’s window switch to the R rear to eliminate that switch as a problem?

 

[petethepug]

Good eye on the right-hand side of things. Welcome to the mayhem! 08 Burb. Nice work on the battery and the cables. hmm ... what's the miles?

Fuel gauge could be something as simple as a bad harness connection above the tank or the float is hanging up on carbon pellets or the float isn't floating anymore. Any way you slice it the tank needs to come down to inspect things.

With this task at hand, it's just time to replace the fuel pump and the carbon canister. It's the labor to drop the tank that necessitates doing the job 100% so you don't have to pay for the labor again.

Lucky you OEM pumps including the sender and a lifetime warranty are $249 at Parts Geek right now. Expect $4-500 elsewhere. Check with the installing shop to see if they want to order it or if they'll let you bring it in so that the labor will have a warranty too. 2nd, that carbon canister that likes to fill the tank up with carbon pellets. Have the tank swab'd and cleaned along with the lines blown out for possible pellets in there. Call it done for the next 100K miles.

Sorry, looked for online coupons for free shipping but couldn't find any. You may have cheaper tax and shipping rates.