Anyone have to deal with a GM PASSlock issue?
 

My 2002 Silverado 4.8 (241K miles) wouldn't start last Friday, after I stopped for an errand.

I have to admit.....the engine had been exhibiting some sputtering on and off for the couple previous weeks.

I changed the fuel filter out a couple weeks ago and had planned on doing the spark plugs next.

What was odd was the "security" light came on...something I had never seen in 19 years of ownership.

With the help of my mechanic, we ruled out the fuel pump.

The truck is over at his place right now and hopefully he can get it figured out.

Prior to taking it to him, I attempted a couple "fixes" including the "relearn" procedure (turn key on for 10 min., turn off for 10 sec., try to start, repeat 2-3 more times) without any luck. I also tried to bypass the little connector under the clam shell over the ignition switch. Again - no luck.

I did not splice in a resistor, but left one with my mechanic to try.

Thought I'd throw it out to the bird collective for input.

GM went through a number of anti-theft systems. The one for my truck doesn't involve a special key other than just having the right cuts. There's a sensor inside the lock with a magnet and hall sensor thingy, according to what I have read.

TIA for any thoughts....

I’m no help, but good luck.

Thank you! SmileWavy

Baz
Could it be the key? Does it have a chip in the key?
I’m just guessing

No chip, Brian.

Never had one nor needed one. Those were for earlier systems.

Thanks!

What's the electronic stuff in the lock for if there's no chip in the key?

I believe I have seen the [pats wires from the ignition switch break on tilt columns more than once in my life .
Do you have a no start, no crank condition ? Or does it start for a second then die ?

(scattering the cards on the table here, to start over from scratch, if it wasn't confusing enough) :)

If he jumpered the fuel pump directly that doesn't discard a blocked line at the tank, bad or intermittent FP relay/fuse, whatever controls the pulses (PCM? ECM?), or ASD(auto shut down) relay mentioned by Fred in another post.

Once had a Bosch relay on a '89 Golf that would overheat with random heat soak after stopping. Or it would not start randomly. Probably a worn pump was drawing too much current. A new FP relay fixed it.

The vehicle might have a bad park/neutral lock-out switch. Or brake switch which releases it. My '95 Subaru would only start in neutral and had to open up the console for the manual shift lock.
Wiggling it sometimes helped.

Another possibility is a bad crank and/or cam sensor. That is another signal required for the engine to start running.

A quality scan tool would show a lot. Especially any codes.

If you can get some "noid lights" at harbor freight if might cut down the diagnosing. Put one on a disconnected injector. They flash while cranking. That means the crank/cam sensor is good, ECM/PCM is good, and it's trying to spray gas. We will assume the timing is correct and not a factor. It would at least burp and sputter.
Then it's off to hunting down spark and actual fuel delivery.

It's not part of the key. It's part of the ignition switch.

The last one, Fred. Engine turns over. Tries to start (1 second's worth) - but doesn't.

Gotta get that clam shell off to get a better look. That one screw wasn't coming out. May end up prying it off.

This article explains some of this:
https://www.locksmithledger.com/keys-tools/article/10238356/general-motors-vehicles-equipped-with-passlock

My mechanic is very sick right now - went to the hospital today to get checked out. I hope he gets better soon. He's a good guy. His son works there too but is slammed. I'm just seeing if anyone else went through the same thing and how they resolved things.

I will check for a pinched wire, Fred, as soon as I can get that damn clam shell off!

Thanks, all. Will keep you posted if I make any progress.....

Thanks, John....good suggestions and will keep in mind! SmileWavy

Have you tried getting an OBDII reading? My money is on the "TBC" fuse in your panel under the hood being blown.

A distributor cap vs. coil-over-plug makes a big difference.
If one c-o-p goes bad, it should still start or run a little worse.
Something that affects the entire system, you got to start swimming upstream to the source.

Narrow it down:
-A clogged cat/muffler will at least start and run for a few seconds or minutes.
-Does the tailpipe smell like gas? Then it's probably spark.
-Air filter okay? Might still be a TPS or MAF/MAP sensor which tricks the ECU into not giving gas.

I have no idea how a GM Security lockout works(spark or fuel) or what triggers it.
Might even call a more distant dealership or search internet forums.

If the key has an RFID but the corresponding ignition sensor goes bad, that might do it.

Have you tried YouTube? It’s bailed me out a couple of times.

I didn't see any common complaints or recalls here specifically, with a brief search: https://www.carcomplaints.com/Chevrolet/Silverado/2002/engine/

Might have missed something.
It might be the security system, or something failed triggering it?

Thanks all.....my mechanic is back at work on the truck and I will be visiting him tomorrow to catch up with his latest thoughts.

Hoping it's something small and just needs to be ferreted out.

I tried my OBDII, Grant and it didn't reveal anything. Maybe my mechanic has a better version.....

I've been using my Volvo to get by while waiting to get my truck going again.......

http://forums.pelicanparts.com/uploa...1732586045.JPG

http://forums.pelicanparts.com/uploa...1732586045.JPG

http://forums.pelicanparts.com/uploa...1732586045.JPG

http://forums.pelicanparts.com/uploa...1732586045.JPG

http://forums.pelicanparts.com/uploa...1732586045.JPG

Buddy of mine with a Taco has been out of the country for the past week and just got back so I'll be able to borrow his unit this week as needed.

Volvo seems to be doing fine…

Redundancy is good!

Dave.

I’m not sure which part It is, but it’s the one that tells the fuel pump to run, after the initial start…. ECU or ECM?

http://forums.pelicanparts.com/uploa...1732588894.jpg

The ignition key for my 86 El Camino broke in half when I dropped my keys. The key and lock was so worn after 32 years of carrying it in my pocket that I just replaced the ignition lock and had it re-keyed to fit my door lock. The only down side is I can't lock my glove box, but in 33 years of driving it, I never locked the glove box anyway.

No fancy and expensive electronic key gadgets, and I have never had to replace a battery in my keys.

Good luck with figuring out a replacement.

Yep! I used the last one - the '69 - all the time for hauling bedding plants to job sites.

When I first got this one, I briefly looked into getting a trailer hitch for it. I think I will pursue this again. I have a very lightweight aluminum trailer that would be perfect for hauling stuff when I didn't want to use my truck.



ECM - but it's not that simple. There are other components involved. Gonna try to get an exact diagnosis before I start replacing stuff and potentially getting nowhere.

Hopefully it'll be something simple.


The trailer:

http://forums.pelicanparts.com/uploa...1732590618.JPG

Yeah - as near as I can tell the key for my truck doesn't need to be anything else except the right cuts. There's something else happening that's the problem, Glen. Thanks!

The Porsche dealer will sell a brand new key cut from the VIN and all one needs is a title to prove the car is yours. Have you tried the dealership?

I already have a key.

Just can't get the truck started.

Quick update.....visited my mechanic this morning and despite his efforts was able to confirm he's still not sure where the problem is. We even tried to get any codes but was unsuccessful with that.

I made the suggestion we replace the entire ignition assembly and then go from there, so I have one coming from Amazon and we'll try again next Monday.

I also ordered a new ignition wiring harness to go along with the assembly.

Will post again with any updates. Sooner or later I'm confident we'll figure it out.

My ignition lock has been acting a bit stubborn now for several years, so I feel that will be money well spent.

Quick update. After installing a new ignition assembly with new key and new wiring harness without any luck on the starting problem, my mechanic is now telling me it's the BCM (Body Control Module) so I ordered one on eBay today that will be programmed to my truck's VIN.

I truly hope this will do the trick!

You should see my dash......the whole thing has been taken apart!

The pre-programmed replacement BCM arrived today! Normally UPS is here early afternoon but today it was delayed to around 4:30, so was too late to test out by Ivan, but that will happen tomorrow morning. Fingers crossed!

(replacement unit on right)
http://forums.pelicanparts.com/uploa...1734152744.JPG

I also ordered the trailer hitch for my Volvo and it's scheduled for delivery next Wed. I bought a "Curt Trailer Hitch Receiver - Custom Fit - Class II - 1-1/4" C12211" from etrailer.com. Cost was just under $200. I will still have to buy the draw bar, ball, and wiring kit and will pick those up locally.

I don't know if drilling will be required - will take a peek underneath this w/e.

Just another day in paradise.......;)

Here's what the trailer hitch looks like:

http://forums.pelicanparts.com/uploa...1734153343.jpg

I can’t believe you’re no start. Issue has been going on for this long! I anxiously await the installation of the control module!

"TBC" stands for "truck body computer" also known as the "body control module." Has your mechanic verified the fuse is not blown?

Thanks, Kurt. Agree been going on too long! Frustrating.....


Hi Grant, Yes I checked it a while back and also asked Ivan and he replied he checked every fuse at least twice. I will check again myself.

Yesterday my mechanic Ivan said even with the replacement BCM the truck has the same problem.

Not sure where we go from here but the ball is in my mechanic's court so hopefully he can get it figured out soon.

Is this mechanic a friend of yours? I'd be out of patience given the time and the number of parts he's thrown at it.

If he's your buddy, I can understand, otherwise it's different.

Its eating me alive, that I cant jump in and help . This stuff gets confusing for older guys who are not super techy (myself included ) .
I've been down this road a few times, and Im confideent I could sort this in a day or so .
Im next to positve, that after BCM replacement, there is still a relearn procedure for the key/ign lock cylinder/security system
From memory, it is something like turn the key on position 2, wait 30 minutes, rinse and repeat a few times.
I can look up the procedure if that helps ??
The fix is always the simple part, it is finding the problem where the difficulty lies.
Best of luck ! feel to pm with any ???

Darn, was hoping that as it... the fuse box under the hood over the driver side fender right? If you are going to check the TBC fuse again anyway I would recommend replacing the fuse with a brand new one and giving it a couple of official "cleaning off oxidation" up and down jiggles in the fuse box while you are at it, but if that doesn't do the trick I am out of suggestions. I hate problems like this... good luck Baz!

Thanks guys......I'll go see my mechanic tomorrow and get an update. Hopefully he has a plan to get it resolved.

At some point I'm not opposed to seeking help from a different shop, although I hope it doesn't come to that.

Truck issue resolved! I was the one who did the re-learn when it started today. We used the old BCM too. Ivan said the one I got from eBay wasn't working, so I sent a message to the seller asking for his take. But I'm not so sure that one wouldn't have also worked. I think the problem was something else. I asked Ivan and didn't quite understand his reply so will try to verify tomorrow when I pick the truck up.

Can't tell you how relieved I am! :p

http://forums.pelicanparts.com/uploa...1734471449.JPG

http://forums.pelicanparts.com/uploa...1734471449.JPG

http://forums.pelicanparts.com/uploa...1734471449.JPG

http://forums.pelicanparts.com/uploa...1734471449.JPG

http://forums.pelicanparts.com/uploa...1734471449.JPG

http://forums.pelicanparts.com/uploa...1734471449.JPG

Whoo hoo!

Yeah.......x a gazillion! :p

Now to get it all put back together without anything else going wrong! I’m keeping my fingers crossed!