AP5

Truck sounds to be having very similar issues as what has been described. Primary difference being that my truck will at random not start; full power to dash. This issue has gone on for several months now; I'm fortunate to have a backup vehicle so, I can park the truck and not sweat it.

I've had my truck looked at by several mechanics and yet the issue persists. Each mechanic visit has involved a level 2 OBD scanner with interface connection. To date, I have replaced the following with new parts (where available, I've always selected the ACDelco brand):

1. AutoCraft Platinum AGM battery
2. ACDelco Starter
3. ACDelco Alternator
4. ACDelco Coilovers
5. Negative Cable
6. Steering Column Harness
7. ACDelco Positive Battery Cable to Starter Solenoid
8. ACDelco Throttle Position Sensor
9. ACDelco MAF
10. ACDelco Ignition Switch
11. ACDelco BCM
12. ACDelco ECU
13. Bosch Double Platinum Spark Plugs
14. ACDelco Spark Plug Wires
15. GM Fuse-Relay Junction Block

All parts that require reprogramming were done on my truck, e.g. ECU, BCM, TPS, etc.

Items on the way:
1. Engine Harness
2. Anti-Theft Module
3. Ignition Cylinder

Steps taken when the truck won't start are:
1. Jiggling ignition (while turning key)
2. Setting key to "On" position for 10 minutes
3. Attempting Remote Start
4. Manually engaging Ignition Switch with key in ignition
5. Removing and reconnecting Negative cable
6. Neutral Start

None of the above steps produce a consistent resolution. The truck just seems to start when it wants to. The most recent symptom I have seen is that I now get a solid Battery Indicator light on my dash (battery and alternator test fine). Open to suggestions on next steps.

Silverado 12

BadchevyII,
Have you found a resolution to your problem yet? My 2012 Silverado started this exact thing a few weeks ago. Had it to the dealer today and of course they could not duplicate. Seemed to be fine while the shop foreman and I test drove after they had access to it for a few hours. Started again on the way home after about 20 minutes of run time. Thanks Much!

AP5

While my truck was at the shop this last time, we found that the connector to the ECU had a single damaged terminal (on the harness). This was discovered by monitoring each step of the ignition process compared against the electrical diagram. Also during a “No start” instance, jiggling this connection and retrying the ignition started the truck. After that discovery, jiggling that connection was not always the “fix” though. More often than not, disconnecting the Negative terminal and immediately reconnecting provided the most consistent resolution.

Currently the truck is in the shop with the motor out. When I get it back, it will have a new Cam and Valve-train, Rotary Assembly and Cylinder Heads. ANNNND a completely new engine wiring harness, crankshaft position sensor and whatever else I can identify while we’re in there. I’ll post back if my worst nightmare comes true and the “No start” issue persists beyond all of that...

I wish I had a solution or even a decent guess at the root cause but, unfortunately, I’m just throwing money at something I don’t understand with the hope of getting lucky.

Good luck with your truck and remember to always tip your mechanic.

Todd_S

Could there be flood damage?

08 Silverado

My 08 Silvy has starting problems,
One two year old batery died,so replaced with new one,this also just died,doesnt hold charge even after trickle charging all day.
Got some crazy light show and weird sounds from ignition and dash lights,,but NO CRANK
Also got msg; Check charging system so watched all vids on YT but stil have no clue whats the reason bc I have noCode reader to check it
Will take it to the mechanic soon
For those having similar electric problems see this

Irish_alley

check charging system shouldnt pop a code for a scanner but shows your battery isnt charging for one reason or another. you can take the battery and alternator or whole truck to a parts store and they can test those parts for free. if the battery is too low they wont be able to test it but they can also charge it for free. but at least you will know if the alternator is good or bad

08 Silverado

Problem was lose,dirty batery cable conection,,.cleaned and tightened up and all is fine,truck starts ok

bmarchi

hey CtandC any updates? I'm having the same problem, i own a 2013 Silveredo 1500 4.8L It usually happens in the heat, electronics don't like the heat. also happens when I'm in stop-and-go traffic or 4x4ing slowly uphill.
codes are consistently
U0073
U0101
U0100
U0109
and at random, a bunch of P codes, i assume those are triggering because of the loss of communication.
Things I've replaced so far

-ECM
-TCM
- terminating resistor (above the spare tire)

im also at a loss of what to do,. its been almost a year since I've owned this think and its happened since i bought it. pretty keen to fix it.

Mclaughlincole

Anyone have any input on this? I have a 13 2500hd ltz and does the exact same stuff, have replaced battery cables with larger ones that I built, cleaned all grounds, replaced resistor, etc, the only thing that I have done different is i unplug the abs control module everything nothing goes back to normal caster except for the obvious stabilitrac, abs, brake and traction control light comes on, but gauges go back to normal, starts like brand new, bought new replacement and module and tried it and same problems no start, guages going crazy etc, leads me to believe that must have some corrupts or problem with the can/bus line, very familiar with this type of system (class 8 truck mechanic) over the road semis are using it for everything these days, just not sure where to start looking on passenger vehicles

bmarchi

my truck is still going the same thing. I noticed when I’m going slow and applying the brake often it triggers the codes.