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help, husband wants to sell it if we can't fix it

I agree with GMCTD (who is usually right anyways). Most electrical problems are usually related either to connections or switches. The ignition switch sounds pretty funky, and will cost around $150 for the part (via internet parts places). I would recommend GM AC/Delco part, don't sub some weird brand. Make sure all your connections are good - check grounds, power, fuses, etc. Once those check out, move on to other things.

I recommend someone other than you replace the ignition switch, if you're pregnant - it does require crawling under the dash.

All the best,

Rob :)
 
thanks, will forward to hubby, will recheck groundings again. Just replaced batteries but will put the ignition switch on the list to be replaced... anything else?
 
No use confusing the issue with a bunch of additional suggestions - even the new Ign switch won't solve the problem(s) if the system connectivity\termination is bad - there are some pics on the forum that detail the system grounding points and cleanup, incl those on the frame and firewall - also, note the condition of the wiring harness as it crosses the AC evaporator tubing, down low at the firewall - cheap to address, all wiring and termination points must be in appearance like the day the vehicle rolled off the assembly line, or they will not afford proper electrical connection - think how your PC would react with wiring resembling that found under the hood - PCM reacts likewise - restoring system power, ground, and signal connectivity and termination eliminates all but specific module, sensor and component failure, of which the IGN switch is one of - remember: just reading procedures and looking at the problem won't heal the problem - somebody gots to get the elbows dirty to get the job done

Trends, empirically, show these types problems occur each fall\winter and winter\spring transition, when electrical connections suffer worst degradation\deteriorization from cold\damp\wet climes - battery post\terminal\cable corrosion is a fairly good hint of things to come
 
when electrical connections suffer worst degradation\deteriorization from cold\damp\wet climes
Click to expand...

Truer words are hardly ever typed. Throw some salt in, just to get the corrosion going really good, and your electrical system bites the dust - Or is that bites the rust?

These trucks (>'93) are known as *FlyByWire*. The ECM is monitoring some fairly robust signals and some at really small level signals, many of which are referenced to ground. A solid electrical system (grounds, fuse blocks, battery connections, etc.) is an absolute requirement BEFORE you can reliably troubleshoot the system. And by the system, I refer to the entire vehicle! Heck, even our heater controls are electric as opposed to vacuum.
 
okay gmctd, can you point me in the direction of thos pictures detailing wiring grounds and such... thanks
 
Anybody here, less pc-illiterate than me, wanna help the lady find the pics that will help her significant other clean up her 'Burb???
 
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the way i've always cleaned grounds was to crawl underneath the truck, disconnect any wire that was bolted to the frame, clean it up, then reconnect and move on to the next one. make sure to disconnect the battery terminals 1st.

times 3 on the ignition switch sounding bad as well.
 
Need to point to the pics of the specific locations - I cain't even find 'em when I'm lookin' for 'em.......................
 
Thank you guys so much... we looked over the pics and info (the first post for some reason wouldn't allow me to see them but the second one had pictures posted right in the thread and I could see those). Husband is waiting for rain to clear and will get out there... I am very hopeful... someone mentioned adding extra grounds to the engine, is this from engine to the frame? and is this veyr beneficial? I will post what we find with the grounds, fingers are crossed...
 
is this from engine to the frame? and is this veyr beneficial?
Click to expand...

Usually additional grounds are from either the battery negative or from the other end of the big wire off of the battery negative.
These are band-aids... The stock ground configuration works fine if in good shape. YMMV, however, if you run some HEAVY loads - Like some stereo amps, banks of large lights, etc.
 
My Suburban used to be a fire truck. They add more grounds to it. I have not even found most of them. They also changed the ground cable to a bigger 4 ga cable.

The one I noticed is additional ground to the body from the negative battery. It uses 12 ga. cable. This is on both batteries. I think one of them comes from factory. The other one was additional. I started to take it out but after joining this forum, I left them alone. I am sure they added ground on other places that I don't know yet since there are more harnesses running around.
 
hubby got under the hood and checked and cleaned the grounds, he did notice that we don't have a ground from the hood, do we need one of those? When he was near the passenger fender well checking that ground he noticed there was a bundle of wires that had been pulled through the black plastic protective cover adn one wire looked crimped. The insulation was cut and some frayed wires. He jiggled it with the truck running and it actually broke but didn't seem to affect the engine idol. He fixed it and let it idol a bit. it cranking is better than it was. I guess now we need to drive it a bit and see what happenes. We have decided that we are going to replace the ignition switch and possible the silver computer box behind the glove box (he cleaned it but it appears that some soda was poured all over it). If these don't fix it we might just have to sell...
 
The ignition switch is a good bet with what you say all the lights do. Do the lights work when this happens and you open the door with the ignition off?

If when it happens and all the lights go off you can just use a test light or multimeter to see if there is power where there is supposed to be in the fuse panel. With the ignition on the ECM should be getting power so look for power where the fuse goes in.

cycling the switch isnt so bad on the ECM, no worries, I do it all the time on my actual PC flipping it on and off over and over because I have a voltage sensitive video card and a not so accurate power supply that I adjust and click the reset and power button over and over and its been going for years, and these ECMs are so basic and hardened in comparison.
 
Post clear, well lighted pics of the engine bay, hood open...................
 
On our 96 I unplugged & replugged the optic sensor. & it hasn't had the wait to start ghost since. You don't know how scared I an to say that. The last time it went 5 monthes after I messed with all the plugs and fuses & grounds & battery posts. This last time the optic sensor plug was the only plug I touched. A dealer tech told me to try it when the Suburban died & the wait to start light didn't come on. He said for him it's always been optic sensor related.
 
jrsavoie can you tell me what the optic sensor looks like? and where it is?

not sure about if the lights works iwth the dorr open and such will have to try it out, am evyr leary to drive it but I guess we need to take the beast for a run...
 
With your lights and everything failing I cant see if being just the optic sensor.

The optic sensor is on top of the injection pump, which is under the intake. Its a black conenctor sticking up out of it. If that is the issue, then you could have a bad filter on it, if you have a filter at all. Some have a connecter and wire about 7" long coming out of the sensor with a little balck box in line with the wires. This is just a alternator whine filter to avoid interference, but if the capacitor or other part in it fails could cause continuity issues. If you have a filter could always just remove it too.
 
I was under the impression the wait to start light was not coming on & all the other lights were working normally after the vehicle died. And when the wait to start light came on the vehicle would start. This would be exactly what our 96 Suburban was doing. I'm about half fuzzed up here so I could have misread or misinterpreted what I read or my eyes could have been crossed or something
 
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