bandit1730

Hello fellow Chevy owners.
About two months ago, my 2007 Suburban just died while waiting at traffic light at night time. It was like one of those SyFi movies where the ships powers down (I saw how cluster needles slowly went back to zero, but all accessories kept working). Tried starting SUV again and again, but I would get nothing at all except for a faint fan like sound coming from headliner(no clicking/fuel pump sounds, cluster would go out while on crank position and the headlights won't dim at all. Ended up towing it home and I've been trying everything I've been able to find online ever since and still nothing).

Every accessory works. Therefore, I am ruling out a bad BCM. The only clue I have is that cluster is displaying "Service Air Bag", but checked impact sensors and they look physically OK (airbag plugs looking good as well).

I'm mechanically inclined I've researched all YouTube related videos/forums and so far have tried the following.

• Wired brushed all engine bay negative contact points + positive contacts including 175 AMP master fuse on firewall.
• no faults found using one of those Android Torque Pro OBDII readers .
• by-passed starter (SUV will turn over, but wont fire).
• Removed steering wheel cover and checked all plugs and found nothing loose.
• Checked every fuse/relay and all looking good (engine bay/cabin).
• Even though battery is good, tried boosting it and nothing.
• Added additional negative contact from engine block to firewall.
• Airbag Impact sensors OHMS readings = 4.03 and 3.86 ohms at room temperature (78 degrees F. It will read lower at higher temperatures).

NOTE: If flipping testing probes, I will get open reading (in another words, I only get a reading when the COM probe is in contact with left side pin).

Questions???
Does anyone knows what's the OHM reading for a good/new sensor (part # 15854647)?
Is it normal to get an open reading test probes are reversed/flipped?
Would an airbag fault produce these symptoms (no crank/no start)?

About the truck: 116117 original miles - Engine replaced by dealer back in 2012 under warranty with 72,000 original miles (Engine developed a warped engine block camshaft seat. Other than that, really never had any issues with SUV up to now).

Any suggestions are appreciated.
Thanks for viewing,

Joseph

bandit1730

As per my original thread, I tried everything I could find online (Most results pointed to Negative battery cable, ground cables/poor positive/negative contacts).

Since I posted thread, I've done the following
I purchased a LAUNCH VIII OBD scanner and the only code was the air bag sensor (B0083) + "U0100 Lost Comm with ECM/PCM A".

• Replaced Air Bag sensors (nothing)
• Replaced ignition switch (nothing)

Today, being that we are having such a nice weather in Miami and able to work on SUV without the usual heat/humidity, I decided to pull the fuse-box housing (engine compartment) and see if there was anything unusual in the wiring/plugs, etc.. and everything seemed normal. I checked the voltage (with the positive voltmeter lead touching the end of RED 12V cable coming from "Master 175 AMP fuse in firewall") and got 12.59 Volts, but at the same time noticed that the way the cable connects to fuse-box is by way of a contact plate coming from fuse-box housing that inserts into slot at end of cable (see pictures below). I saw what I though was some kind of off-white looking surface covering the contacts and thought "what that heck.. I already pulled the box out, might as well take the cable connector apart and see what that white thing is). Once I had the connector disassembled, it really seemed like the metal connectors were intentionally plated with some kind of protective coating to prevent corrosion. Nonetheless, I found the cable online (ACDelco 25814777 GM Original Equipment Positive Battery Cable) for $58.78 and though that the worst thing it could happen was spending another $60.00 and buy a new cable. Therefore, I used a dremel tool with a wire brush and polished all contact points (plate from fuse housing/slot connector. Note: there is a sleeve that's inserted into the cable connector slot. Take it out and polish it as well). After I was done, covered everything with dielectric grease and at the same time, applied some grease to every socket/contact I could. I then proceeded to reconnect battery terminals and the SUV started on the first try .

Spent over two months to finally solve the no start/no crank nightmare (hope this helps another poor soul with same gremlins)

SabrToothSqrl

Conrats on troubleshooting!