Electrical problem

[Charles Austin Miller]

My 2005 TB LS EXT suddenly has what I think is an electrical short somewhere. Both low-beams and forward running lights stopped working. No daytime lights at all. I can only drive at night using high-beams (which aren't affected). Also, battery is inexplicably draining in 2 or 3 days to a dead battery. When I jump-start the battery, it holds a charge just fine; but, if I don't drive for a couple of days, the battery is drained. That's a short, ain't it? My first suspicion is any electrical wiring near the exhaust manifold (melted insulation). But the real question is if this specific electrical problem is a known 2005 TB problem.

 

[mrrsm]

Deja Vu...?

https://gmtnation.com/forums/threads/2005-tb-lowbeams-gone-not-fuses-or-relay.18410/#post-555116

If your Ignition Switch is going sideways... it may not be breaking the contact connectors completely internally when you remove the Key and hence it can cause a slow Battery Drain Down.

 

[Charles Austin Miller]

My ignition switch is new. This latest development makes me question if the ignition switch was EVER really at fault.

 

[mrrsm]

You might consider using this device and pulling-testing-replacing one fuse at a time and checking them using an in-series, very sensitive Amperage Meter (Ammeter...without the "P") for each response ...until you've honed in on the circuit involved:

This is an updated 'New Techniques' PDF with two articles covering the subject of Parasitic Draw/Drain Testing to help with investigating your rapid loss of battery storage after short periods when the SUV is dormant:

http://flashoffroad.com/electrical/CurrentDrain/currentdrain.pdf

Here are some choices of Parasitic Electrical Drain Testers offered on Amazon:

https://www.amazon.com/s/?ie=UTF8&k...qmt=p&hvbmt=bp&hvdev=c&ref=pd_sl_4ch3xyje3h_p

 

[Charles Austin Miller]

Thank you. I'm still wondering if my backseat fuses have any effect on the low-beams and forward running lights.

 

[cclarkk]

My 08 Envoy developed similar problems. First I lost only the front running lights. Followed by the DRL's. Being I had two 08 Envoys, I swapped parts back and forth to try isolating the problems. Wasn't fuses, relays or the switch. Ended up taking it to the dealership where they found the main fuse block (under hood) was at fault. $550.00 later it was fixed.
Block itself was $267.00. I am not saying this is what happened to yours, just something to consider.