Typerod

Hi all need some urgent help. I had to leave work, wife called and Tahoe wouldn't start. Got home and she somehow got it started. I was skeptical so I turned it off, and tried to crank it and nothing but a single click. I tried jumpstarting but that won't do it. Voltage on both batts are about 12.6. Only recent work done on car was the left front hub replacement. I found that the neg. batt cable on my 2nd batt. was loose, I tightened that down and still wont start, Im currently charging the batts right now as I type this, but I have to get back to work.

I did find that my rear glass switch needs replacing only due to the rubber being worn out and disintegrated. I do remember seeing a thread about a switch shorting out somehow and the car wouldn't start? I can't be sure.....the mega fuse looked to be fine. Can you tell that a mega fuse is bad just by looking at it? or do I need to test continuity?

Car was running fine yesterday for my wife,and ran fine Friday and Saturday, no issues at all. Then bam, today got this issue.

Any suggestions would be gratefully heard! I need to get back to work I've been gone for a few hours now.

TIA!

Batteries are dual yellow top optimas D35's. They are about 4.5 years old. Maybe one has gone bad? I figure it would at least start. So maybe some deep internal electrical fail?

in2pro

Check those battery cables, both ground and positive, you can check for voltage after the mega fuse at the fuse box on one of the extra terminals....

Typerod

Thanks for the suggestion in2pro!

I was able to get it started and keep starting consistently now. OMG! So while I was typing my orginial post, I was charging the batts b/c I didn't know what else to do....went outside batts were fully charged, disconnected the charger and tried to start it......NOTHING. I said ok, let me pack up my extension cord and charger and I put those away, cuz I had to get back to work, I was gone for a couple of hours +.

Then I said for poops and laughs, let me finaggle that rear tailgate glass switch (i really thought I recalled a thread about this tailgate glass switch causing a no-start issue from years back). I just put my key into the switch to hit the button, but it didn't pop the glass. Then I went and put the key in the ignition and the dang thing started right up, like it was nothing. LOL! WTH! I turned the car off and it restarted itself just fine. I turned it off again and turned the key and it started again! I'm a teeny bit skeptical that the switch is the issue here, but it just could be it. I have a new switch on order from Amazon.

Let me see if I can find that thread about some type of door switch or something that caused a no-start issue.....

73shark

Unlike older vehicles where the ignition switch (key) actually applied voltage to the starter solenoid, most now have the switch send a signal to the ECM which then tells the starter to start the engine. That's why the starter won't stay engaged even if you hold the key in the Start position. Actually all that's req'd to start is to just twist and release the key. No need to hold in the Start position 'til it starts.

Kind of like if you just tap and release the turn signal, it will flash three times.

Typerod

Oh wow, you just blew my mind! lol! This whole time I've been starting my Tahoe by holding the ignition in the start position until the engine started, lol. Thanks for the info!

UPDATE: Haven't had any issues since I jiggled that tailgate glass switch. I'm still not totally convinced that the tailgate glass switch is the issue.....

in2pro

I believe its labeled as " convenient start feature"

ecullen

I have a 2008 Suburban, everything was fine with it until last night. My wife comes home shuts the vehicle off. Hour later go to start it nothing. The lights come on like normal all the gauges come on just wont turn over, no power what so ever to the starter. Checked to make sure the gear selector is in park, tap the starter just incase of a dead spot. Battery is fine.
Has anyone had this problem and came up with the solution?

Typerod

Sorry, I feel I haven't truly found the cause of my issue. And I probably won't until my Tahoe won't start at all for a longer period of time. As suggested previously in this thread, check your battery cables for tightness, check your battery voltage to see if its up to par, check your mega fuse to see if its still good....good luck!

I was recently playing around with my tailgate glass switch to see how to replace it, since the rubber cover has disintegrated and fell off. I figured out how to pop the switch out, and had a difficult time doing so that I left it half popped out, to make it easier to replace in a few days when the new switch arrives. After trying to trouble shoot on my own and getting advice from members here, I gave up. Then I remembered the switched was left out, and I swear up and down I remember a thread about some type of door switch or the tail gate glass switch was failing and causing a no-start condition. So I just stuck my key into the hole to push on the switch to pop the tail gate glass open, but it did not pop open. Then I went to the ignition and put the key into it and turned to the start position and the car cranked and started just fine. So weird....you're not having issues with your tailgate glass release switch are you? lol!

73shark

Welcome to the forum. Do the lights dim when you turn the key to the start position?. If they don't, then the problem is with the starting circuit.

ecullen

Yes I checked the battery and its charged, the lights do dim when I turn the key to start position. I have noticed I haven't heard the fuel pump, that maybe because the fuel system is fully pressurized.