re-set computer - won't start

CARDER001 · March 1, 2014

I just purchased a used 04 Silverado. I've been having issue with the keyless entry (it suddenly stopped working). I thought if I re-set the computer (unplug the battery for 30 minutes) and plug it back in, maybe it would work again... Tried that, now it won't start. It sounds like it's going to, but nothing... Let it set 30 more minutes, same procedure, same result. WTF??? It has a new 7 year battery too... It was running and starting perfectly all week.

txab · March 1, 2014

Factory keyless or aftermarket?

CARDER001 · March 1, 2014

update: I disconnected / reconnected the battery again (after 3 Hours). It started right up all the lights/accessories, every thing is back to normal. The Factory Keyless Entry is still not working, but I can live with out that.

esox07 · March 1, 2014

Here is my guess as to what the problem was with the non-starting issue. When you disconnected and reconnected the battery, you didn't quite get it connected good enough. I know you think you did, but somehow, the connection wasn't good enough for the necessary power. After disconnecting/connecting it a couple more times, you finally got a good enough connection. But, it might signal a future problem developing. Then problem might not be directly with the battery connections but maybe with the ground to the truck frame or somewhere else. You messing with it, may have made the difference, just like hitting a pothole tomorrow on the road might do. I would give the system a good look over and fix any corrosion or loose connections that I see. Sometimes the battery cables can have massive corrosion inside the wires, under the insulation that you can't see.

Then again, it could just be the electrical gremlins which is a good bet as well.

If you have two remotes, and neither works any longer and they both died at the same time, I would expect it is something to do with the system in the truck and I would have no idea where to go with that other than the battery reset which you already tried. If it is just one remote not working, then the remote fob battery could be dead or the circuit board could have went bad. In that case, open it up, try a new battery and look for any corrosion or loose or broken connections on the board.

CARDER001 · March 1, 2014

SOUNDS LIKE GREMLINGS... I DID TAKE IT OUT FOR A SPIN EARLIER AND NOW THE IDLE IS ROUGH (SOUND LIKE IT'S ABOUT TO DIE WHEN I STOP)... It was running flawlessly, until I started messing with it....

txab · March 1, 2014

Keep driving it. It should clear up.

You mention Gremlins.... as esox07 mentioned battery cables/connections can cause issues as well as poor body grounds

CARDER001 · March 2, 2014

Keep driving it. It should clear up.

You mention Gremlins.... as esox07 mentioned battery cables/connections can cause issues as well as poor body grounds

What about those poor "body grounds"??? I've heard this mentioned in several internet searches too.... The cables appear to be perfect, and the battery is a new NAPA 7year, and as I already mentioned, it WAS running perfect..... Thanks for the help/advice!

PhilB · March 2, 2014

GM had some bad Delco batteries that would leak acid out the side post mounts, especially on the positive side. Sometimes the battery cables would corrode inside the insulation, and you wouldn't see it. You may want to replace the battery cables to eliminate possible gremlins there.

txab · March 2, 2014

What about those poor "body grounds"??? I've heard this mentioned in several internet searches too.... The cables appear to be perfect, and the battery is a new NAPA 7year, and as I already mentioned, it WAS running perfect..... Thanks for the help/advice!

When you disconnect the battery the ECM goes through a relearning process. Usually there is no problem and it will run fine. But some have reported having your issue and it has cleared up with just a little driving. These vehicles can be sensitive when it comes to electrical system. That's one reason good battery connections/cables are important. Around the truck, there are grounding straps connecting the frame, engine and sheet metal so that electrical circuits can be completed. If you have dirty, rusted connections, then sometimes elctrical issues arise