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Help with ignition issues

Rothy

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Nov 9, 2020
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12
Location
Reading, PA
Hi new here and i registered after doing days of research and reading hundreds of threads and google searches and still haven’t found a fix.. I’ll try to include all possible information and a quick timeline of events. But as of today, 2 auto shops and the local dealership have not been able to get it fixed and I made more progress on it myself than anyone ( I am an experienced automotive technician) so;
Problem: no start/no crank
Symptoms: -key activates dash, and all other electrical when turned into the on (run) position.
-all lights and electronics go off when you turn key to start and hold as if starting truck and come back in when you let key go but no crank, click, anything when held in start position (normal function minus no crank)
-keyless entry functions normally
-brand new battery, alternator, serpentine belt from previous owner; (I’ve only owned it for a few weeks) you can see the parts are brand new though. I replaced that new battery with another new one myself in Monday hoping to get some kind of response
-non of the cigarette lighters have any power anymore
-will start when jumped at starter solenoid when key is in run position (it’s how I’ve been driving it the last two days)
a) trucks runs and drives when started this way but the turn signals don’t work. The four ways, drl, brakes, reverse, automatic function, low and high beam all seem to function normally though.
b) it will always default the memory settings when I start it even if I set them beforehand
- if I disconnect battery while running the truck will run for about ten minutes on its own then shut off but will start back up with above procedure when I reconnect battery (battery light comes on as expected when I do this and goes off when I hook back up)
-sunroof doesn’t work and has no power at plug
-same symptoms mentioned if truck is tried to start in neutral or park.
-truck will start in reverse park and neutral gear when jumped at starter but not with key ( did not check any others yet) but gear selector reads proper selection in cluster
- no check engine light no codes
- air bag light is now on and will flicker intermittently
- code readers will not connect to the truck now , they will only continue to try to communicate and fail
- tachometer reads zero at (almost) all times but all other gauges, at lealeast the ones that worked beforehand, work. Sometimes it will jump and fluctuate and sometimes actual read normal for about 10 seconds before dying again and this is intermittent and rare
- pcm fuse has 12 Volts on each side
- truck read ~12.4 volts everywhere when checked with millimeter and was hooked up to running vehicle with cables
-checked all cables, removed all grounds and cleaned/ replaced parts for solid connection
-checked every fuse relay harness plug

new parts:
- alternator
Battery (now top post with new terminal connections)
Starter and ecm relay
ignition switch
Light control module (flasher relay)
Starter
Every fuse and lcase fuse is replaced with


timeline of events:
Couple days after I purchased it truck wouldn’t crank when I started it all lights worked and went off when in start position (like it usually does) but no crank. After throwing it in neutral to coast it somewhere for a jump start and a couple turns of the key out of aggravation it fired and was fine. From then until about
Two weeks ago no issues starting until one day last week the truck shut off on the highway out of nowhere. It was like I turned the key off; it immediately died, and all lights shut off on dash. While coasting to the best place to stop I could get too, turning the key off and on and trying to start yielded nothing at all. Not even lights. While stranded trying to get it to start I managed to get lights and four ways back by pulling battery cable and reinstalling but not crank. After over a half hour of checking fuses, cables, relays, tapping on every ignition component I still got no crank and no turn signals. Because of the no turn signal issue i decided to pull the right front turn signal bulb simply because I was out of ideas. Coincidentally when I did this and tried to start the truck it cranked and fired! I took off heading for home before it happened again and stopped at the local parts store I passed hoping they could check my starting and charging system and check for codes because the CEL came on when it started. Because of the COVID 19 poop they weren’t allowed to test people’s vehicles so I went to leave and again no start but dash light up. After 20 minutes of trying everything I could think of I finally pulled the alternator plug and the truck started up! I reconnected it and drove home with no other issues. Next day wtruck shut off while driving again after the tachometer dropped to zero and fluctuated, after checking fuses etc once again it intermittently started after an hour. This time the tachometer did not work. It came on and off a few times racing home, then finally stayed at zero until I got home.towed to local auto shop for repair after not starting next morning. Shop spent 2 days on it and couldn’t repair issue. They tried jump starting it without success as well. I told them to do what needed done to get it fixed because it’s my only vehicle so they started throwing parts at it I guess hoping it work. They replaced the ignition switch, light control module (flasher relay) and diagnosed it to be the ignition key tumbler. They called the local Chevrolet dealership for the parts and asked them for advice. The dealership claimed it was the key lock and needed to be replaced and programmed by them. So I tow truck to them. After two days there they call me and say they are refusing the work and demand I remove the vehicle from their lot with no other explanation. They claim to void the service charges it had from diagnosis because of it which they did. Paperwork said 2 hours. But didn’t go into detail about anything at all. After 8 hours of working in their lot myself; checking fuses and harnesses and plugs throughout entire truck with a multimeter, I got it to start by jumping the starter and drove it home and this is the current status of it. So I’m absolutely lost and sick of throwing parts at it . I apparently have no help from local dealership so I’m hoping anyone can have any input or answers for me as to why my truck won’t crank with key. Is it the alternator intermittently dying and coming back; is it the ignition key cylinder, the neutral safety switch, the cluster???? Is I possible it’s in theft mode (even though the lights not lit and the alarm and security light both function and activate normally) is there something I’m missing??

I’m sorry for ridiculously long post but I wanted as much information as I can remember to help someone hopefully help me I’m sure I missed a thing or two as well and if so will come to me if mentioned or reminded. But I have over 1k in labor parts and tows with this thing and no shop can fix it and it’s still not right so I’m really praying I can get some answers or suggestions from here thank you
 
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Randy

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Wow.. First welcome to the club and sorry for your troubles with your AV. Looks like most parts and various things to check like grounds that may be related to the problem have been changed. What year is your AV? My only suggestion at this point would be to check other grounds if that hasn't been done like for the main fuse box, instrument, engine harness and other wiring harness grounds there are many.

Also since we don't know the year as of yet does it look like it has a aftermarket remote starter added, those can be a problem or and aftermarket security system, another source of problems if not installed correctly. Other here have posted problems from rats chewing wiring under the hood causing starting problems..

So in short I would inspect the wiring harness under the hood and under the dash for cuts and splices..

Good luck in your trouble shooting..
 
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old skool

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Like Randy said above...I have an aftermarket remote start on mine that was giving trouble like you say. Traced the wiring back from the remote start connections, and it turned out to be a loose wire connection in the fuse box down by the drivers side kick panel.
 

EXT4ME

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Sorry to hear of all of your problems.

What a nightmare.

Have you pulled the under hood fuse box and looked for rodent damage?

Also, have you come across anything that suggests this truck may have seen some flood damage?

I suspect there is some hidden wiring damage that you have not found yet.

Hopefully, the damage is isolated and once it is found, the rest of your issues go away.

I wish I had better guesses for you.

Best of luck.
 

Rothy

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Location
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I ******* FINALLY FIXED IT AND EVERYTHING SO FAR (please pray for me) is working as expected from factory. I even fixed a few problems caused by P.O. and I’m assuming one of the shops. So... for future references to similar problems this is what I accomplished:

I believe the trucks Ignition lock cylinder was going bad since I’ve owned it but wasn’t enough to no start or set off security. (From what I’ve gathered the lock cylinder is where the passkey 3 communication is) so the unstable connection for passkey 3 is where I got my radio/alternator/battery/ gauge cluster etc etc etc intermittent issues from leading up to it actually stop working completely. Because I am ocd and research everything and properly diagnose a problem unlike some places that just throw parts at it because they made an educated guess; they programmed my new switch to the original DEAD PASSKEY lock cylinder, and never reprogrammed the fob. which erased the required sequence needed to start truck. Which in turn put vehicle into theft mode which I did not know right away because I have an aftermarket head unit from P.O. so thought I was just back at square one. After diagnosing a popped mini fuse during this I came to the conclusion and I bought a new lock cylinder. After doing the passkey relearn procedure five ******* times with no progress I had to pull pcm fuse for 30 seconds then reinstall original ignition switch and old key relearn the passkey to original key (still didn’t start) pull battery for half hour then install new switch with new key. Before I programmed the key I had to program fob to truck, pull pcm fuse for 10 seconds AND THEN program the key. If I didn’t do this exact sequence I accomplished nothing. So I’m going to assume it was either in a security mode through passkey since my first break down and truck really didn’t want to get stolen 😂 or it fell into some kind of open loophole in anti theft because of the chain of events it went through. Either way this repair took me 3 days to properly diagnose and accomplish. And I’m more happy and proud I got my truck running again than any job I’ve worked on yet and the almost thousand dollars spent from other peoples assumptions... it is taking everything I have not to drive truck back to dealership and slowly drive through the service department with all my lights and four ways on blasting the radio and flipping the bird all the way to the other end of the shop .

Thanks for response guys. It’s an 05 z71 I thought I put it in my profile but I guess not...anyways i REALLY FREAKING hope this Information can help someone else one day who is at a loss. I also have passlock programming service bulletin that the dealer charges 400 bucks for I just have to figure out how the hell to post pics I forget
 

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Glad you got this nightmare sorted out.

You can post pictures after you have a certain number of posts.

It's not too many, so keep posting.

:) (y)
 

Rothy

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lol ok I’m not planning on going anywhere, there’s a wealth of information here and I actually really do love the AV it’s perfect for me with my business and family as our only vehicle. Maybe now I can spend money on mods instead of repairs ...😅
 

Rothy

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Reading, PA
Well it made it almost 24 hours running perfectly no hiccups running around i put over 150 Miles on it and shut it off and restarted it with the key at least 50 times at least I went to Pizza Shoppe to get dinner I shut it off and locked it came out with the pizzas and the truck is back to not starting.! Once again it starts by jumping the starter but I have no turns signals . I’m just done with this. I give up. I can’t comprehend how I managed to get the key to start truck and now it’s not the culprit. I can’t possibly imagine the brand new cylinder went bad in a day and I can’t for the life of me think of anything that would cause it to randomly lose its synchronization with the truck. Is anybody in my area that would be interested in checking it out with me maybe a second viewpoint???? I’ll supply food beeer whatever you want I’m near reading Pennsylvania
 

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Without going back and re-reading, did you replace the actual ignition SWITCH and not just the key tumbler?

The ignition switch, which is attached to the key tumbler in the steering column next to the key tumbler, has been know to cause many electrical issues in the past for some owners.

Trying to do some spit-balling here for you.
 

Randy

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Glad to see a resolution to your nightmare..

Like EXT4ME says was it the actual ignition switch that was the problem?? I thought that was replaced by the dealer in the beginning, so was it replaced twice??
 

Rothy

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Without going back and re-reading, did you replace the actual ignition SWITCH and not just the key tumbler?

The ignition switch, which is attached to the key tumbler in the steering column next to the key tumbler, has been know to cause many electrical issues in the past for some owners.

Trying to do some spit-balling here for you.
I replaced the ignition switch AND the key lock tumbler the switch which is snapped in underneath the key lock cylinder by two tabs, and the key lock cylinder in the column. I reprogrammed the pass lock to the new parts and originally it worked for almost two days now it’s a no crank no start again. I tried programming key again to no avail. *also to note* the security light comes on and goes off within 5 seconds of turning key to run it also does NOT come on while driving when I jump the starter
 

Rothy

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Location
Reading, PA
Glad to see a resolution to your nightmare..

Like EXT4ME says was it the actual ignition switch that was the problem?? I thought that was replaced by the dealer in the beginning, so was it replaced twice??
Apparently the problem hasn’t been rectified yet I just somehow got lucky for a day idk I’m at a total loss
 

Rothy

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So continuing on my story: 7 days later and it’s starting and running again with the key in the lock cylinder. Abs light is still on, check engine light is on but can’t check codes (more on that later) turn signals and all other lights and indicators work properly. It’s been a day and a half so we’ll see. I have it narrowed down to a short from getting wet when it rains etc. haven’t owned truck long enough to know this but the sunroof and/or rear spoiler whatever that’s called leaks in the rain and the driver door is off alignment slightly and leaks at the top of the door at roof and soaks the floor and driver door panel. How’s I find this out? I thought I’d be nice to it so I jumped the starter and took it to the local automatic car wash to clean up the undercarriage since I figured I’d be spending allot of time under it fixing this problem. I got SOAKED!!! I thought I accidentally left my damn window all the way down it was so bad. Well as soon as I could say “oh sh*t” I heard a pop, check engine light came on, truck idle changed, tach started working again and everything. It popped the ign E ( I think don’t remember now) fuse from this. Get it home replace fuse try my best to dry inside. and truck runs fine. This morning I go out to check on it and now both front floors are wet down to the metal. I pull them up and dry it out. Install new door speakers while I wait (which was a total waste of money) . Ignition E and radio amp fuse are pulled and battery disconnected this entire time. I reconnected everything, reprogrammed the key once again since I pulled battery, went to leave to do a crankshaft position sensor test, and I have my foot on break. As soon as I grab lever to shift to drive and the door automatically locks in gear (how I have it set) the check engine light comes on and tach dies. I already know what thi means I shut off truck in driveway and try to restart and no crank no start. Also the oil pressure gage is zeroing out at halfway now. This is leading me to believe a short in door lock? I checked fuses and it blew the b:u fuse I think and here’s the best part: when truck is hooked up to scanner and it’s jumped off starter the scanner won’t even turn On. When truck is working right and starts with key the check engine engine light comes on and when you plug in the scanner it pops the cigarette light fuse (I know they are same fuse) so you can’t Check whatever codes are stored there. So idk I guess I keep playing Russian roulette with this pos until it gives me a stroke
 

Flyfishdelta

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Jan 11, 2021
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Rothy, you ever figure out the cause?
My 2002 ran fine, took it to the store, came out and no crank no start.
same dashlight symptom as you stated. I changed the starter (all the insulation on the cable between the solenoid and starter was gone, dry rotted and cracking off) all my fuses are fine, (checked them all with a multimeter, jumpered the start relay and she cranks fine, jumped the crank fuse at the kick panel, and cranks normally no start. I'm leaning toward the key lock cylinder and start switch, might as well change them both since its all opened up. Before I do all this (parts $ and time) looking to find out what your final issue was. Thanks
Steve

update:
New key lock cylinder, then I found it, Yellow wire from the ignition switch pulled free, very tight along the steering column, tilt in the up position puls the wire tight.. I soldered the wire back on and crank start... all good- hope this helps someone..

Steve
 
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Vaeagleav

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Rothy was last on Nov.23rd, 2020 so you may not get a reply from him....(fyi if you hover your courser over a person's profile it gives you last date for person on the website.)
 
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