So, here I am trying to get my 2000 Silhouette van back on the road, and all of a sudden I have a "no start" situation!!! Started off with all sorts of weirdness happening with the dash lights: one day they all lit up randomly, and the van wouldn't start. A bit of fiddling around (set and reset the parking brake, held the brake pedal down while attempting to start) and it started. I was able to drive it home and park it in the driveway. Next day, similar problem: wouldn't start until I held my foot on the brake pedal, left the key on for about 15 seconds, then turned it to start. It started up okay, but most of the dash lights stayed on ..the "rear liftgate ajar" light wouldn't go off, even after I opened and closed the liftgate (where's the switch for that door, by the way???). Later that day, the van refused to start at all. I pulled and checked all the fuses, on both fuse panels (all good); checked the starter relay by the battery ...switched it with one of the other same relays, no help. So I took the starter relay apart, plugged it back in, and joined the contacts: starter works, but even with the key in ON position, the engine wouldn't start! So, that's when I started to think it might be the PASSLOCK III system, which shuts off the starter and the fuel supply if it doesn't recognize the chip key. So, I used my second chip key ..no luck. Then, I did a BUNCH of googling, and found out what a nightmare the GM PASSLOCK system has been!!! ...and settled on that as the likely cause of my "no start" situation. After numerous tries and retries, the warning lights finally stopped coming on: all I get now is the shift light, and the bong-bong-bong of the warning bell. Never did see a SECURITY warning light.

Then the fun began: I started checking for bad wiring, poor connections, etc. --anything that might be the cause of the problem. I checked the wiring harness under the driverside threshold: very good condition. I checked under the passenger side threshold: not so good. It appeared there had been some water in there, as there was rust in the channel. Took the tape off the harness and discovered three very "iffy" connections: one where two yellow wires were merged into one yellow; another where two orange wires were merged into one orange, and another where two whites were merged into one white. They were very poor crimp-style connections COVERED WITH BLACK DUCT TAPE !!!!! Is that "factory" ???? Of course, the duct tape didn't keep the water out ...so the connections were all brittle and corroded green. I cleaned them up, spliced in new wire, soldered the connections, cover them with heat-shrink wrap and re-taped them with plastic electrical tape .....all the while thinking this was finally going to solve my non-working power rear side windows problem. Didn't make a difference ..they still don't work! Next, I took apart the switch unit under the ignition key cylinder, and cleaned the contacts inside the black box ...they were fairly pitted. Didn't make a difference. If it did start, I was going to use some on-line instructions I found to completely disable the PASSLOCK system by clipping the sensor wire from the ignition lock and putting a switch in the line.

I've tried all the "10 minute - 10 minute - 10 minute then start" suggestions. No luck.

So, now I'm at roads-end: perfectly good (well, it was anyway) van sitting in the driveway, and it won't start. I'm 60 miles away from a GM dealer, and will likely have to have the van towed there and give them a blank cheque to fix it.

All this, to ask the question: is there a way to disable or bypass this PASSLOCK thing while the van is not running ...ie: "hot wire" my own van ...???

Any and all suggestions very much appreciated!!!!

 

I would recommend you look in the Alero section, the first sticky post has instructions on a more reliable way to disable Passlock. The clip/switch method you describe will only work if the van is running. If you do it not running, the van will think a theft is in progress and not start.
The resistor method will work whether the van is running or not, you are essentially fooling the Passlock II system into thinking it sees the correct resistance all the time. BTW, if you have a chip key, you have Passkey, not Passlock. The article in the sticky describes the various systems in detail, with troubleshooting tips.
Given that you have no security liight, I would guess that Passkey is not your problem. It sounds to me more like an ignition switch (not cylinder) or ECM issue.

 

Thank you very much!!! I was wondering if I was EVER going to get anyone interested in this. From my googling, there seems to be quite a few issues with the security system on this vintage of GM products, so I figured some else must have had similar problems. Yes, I found the the detailed instructions on the "resistor method" ...and will give that a try. I do have the "chip keys" ...so I guess it must be a Passkey system, rather than PassLock (although the device under the ignition switch on the steering column does have big sticker saying PASSLOCK III). I have a replacement ignition switch (used) on the way ...it includes the harness and the key. Will I have any issues trying to have the system "learn" a new key, or will it matter once I've done the resistor bypass? When you say "ECM" issue, which Control Module are you referring to? Again, thanks for any and all help.

 

All the resistor bypass does is simulate the correct key resistance. A key with no chip will start the car once the resistor bypass is done because the system sees the correct resistance no matter what key is used.
You'll have to read the article to confirm, but I seem to remember that there are 15 different resistance values for Passkey. I don't think Passkey has the ability to learn a new key, but I think the switch is not reading the resistance, there's another box that handles that, so you should not have an issue with a different switch. Again, read the article to be sure.
ECM=Engine control module, BCM=Body control module
I am much more familiar with Passlock than Passkey, and I am not certain how Passkey interfaces with the ECM. Passlock prevents the ECM from enabling the fuel injectors, and locks out the starter on some vehicles, so I would expect Passkey to be similar. I know on my 95 Cutlass, Passkey would lock out the starter, so it should be the same on your van.

 

WOW ...I'm SO happy!!!!!! Problem solved!!! After doing BUNCH of research here on the web, I came across a post from a guy who said he solved this problem by replacing the ignition switch (not the part where the key goes in, but the switch underneath that part ...the mechanism that the harness wires go into). The guy said he took the switch apart and cleaned the contacts ..I figured it was worth a shot, but it didn't help. So, I found a used ignition keylock, key, switch and harness (from a 99 Montana) in Ebay, and got it for $40. The unit arrived in the mail yesterday, and I installed just the switch and harness this afternoon. (kept my existing ignition keylock, key and PassKey III unit). Wow ....I felt like doing a handstand after the van fired up right away!!! With all the problems other folks have reported with these Passkey systems, I figured I really dodged a HUGE bullet this time. I plan on doing the "resistor" bypass process anyway, just as a preventative measure against future problems.

Thanks to everyone who chimed in and tried to help out! I really appreciate it!!!