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I have a 2003 tahoe and Im having some trouble upon starting the tahoe. When I go to start it  seems like the battery is dead (but its brand new) it turns over slow sometimes and starts ups. The radio resets itself to 12:00 oclock. If I turn it off and start it right back up it starts fine. If I wait for a minute or so it does the same thing starts slow. Always starts though. If I just turn the ignition to run but do not try and start it the radio is keeping the right time. Just when I go to start it it seems like it drains itself or something and radio goes back to 12:00. Any help would be  wonderful.  

stop by a hardware or paint store.. pick up a wooden handled stainless steel wire tooth brush..  they cost about 2 bucks..

disconnect the battery..  you will probably want to remove it from the engine compartment..

remove the battery terminal bolts from the rubber boots by unscrewing them to free it from the ring terminal.   you will want to examine the hidden ring terminal inside the rubber boot..   if you see corrosion in there.  you can pour hot water over the boot and use a screw driver to pry the rubber boot loop over the ring terminal to allow you to wire brush it clean.. more hot water to wash out any corrosion.. .   you will also want to wire brush the back of the battery bolts..

you will notice that i did not mention baking soda..  hot water really works great to wash off corrosion..  when a stainless steel wire brush is also used..  conventional steel wire brushes work.. the brass ones are just too soft..  the plastic handle versions are usually equipped with very fine wire that does not do as good a job cleaning the hard crusty stuff off..

follow the negative battery cable down to the bottom front of the engine block..  or to the side of the engine block above the oil filter ..

count the wires on the stud .. remove them..  wire brush both sides of the ring terminals.. wire brush the stud..   reinstall.. count the wires to verify they are all still there..

remove the positive battery cable end from the starter motor...  wire brush that and any other wire on the that post.. there is probably only the starter cable..  

find the fuse and relay box over by the master cylinder.. there is a 4 gauge battery cable from the positive battery to that box.. again.. remove that cable and wire brush both sides...   wire brush the mounting point..   put it back together..


one you do this.. as it will take probably an hour..  to do this job properly...   i have a volt meter test for this also..

one thing...  GM cars and trucks have been using a music box type of ignition switch.. once in a great while they go bad..  but it will not cause your truck to crank slow..   dirty battery cables do that...  dirty connections do that..   bad starters do that..   cleaning the battery cables is needed before you start replacing stuff...  

lets start with the simple and cheep stuff...

do you have a digital volt meter... if you don't.. they can be had for 7 bucks to 25 bucks..

a lot of parts stores have these from innova for about 16 bucks..



harbor freight stores have these for about 20 bucks



either will last you for decades..


next.... i would take a digital volt meter...

set it to 20 volts DC scale...

start the engine and turn on the headlights..

1. test between the positive and the negative battery posts.  14.1 to 14.8 volts is expected.

2. test between the negative battery post and the engine block. 0.04 volts is expected..

3. test between the negative battery post and the body... 0.02 volts is expected..

4. test between the Engine block and the body..  0.02 volts is expected.

if you get 0.00 on the last 3 tests.. change the meter setting to 2 volts DC scale.. and retest.. the last 3...

this test takes about 2 minutes...

post your results by test number..

if you get more than the 0.04 or 0.02 volts on the display...

you have a bad ground between those parts..



why do this test....   bad grounds will stop any new car in its tracks...

why... electrons flow from Negative to positive...  if you loose a ground.. or it becomes intermittent..  you won't have any power for that circuit...  just like a table light when the plug falls part way out of the wall...  the light will go out..

also i have fixed a LOT of cars lately with that  2 minute test... some hot water and a stainless steel wire toothbrush ...

finding the ground connections.. removing them from where they are bolted down after counting how many wires are on each one..   wire brushing both sides of the ring terminals...   wire brushing the back side of the nut.. wire brushing the mounting pad...  washing with HOT water..  

putting them back on.. and counting to verify the number of wires is the same...

the verifying with the same test again...

i just wanted you to see the inside of the ignition switches.. again. this will NOT cause it to crank slow...