security light (cranks, no start)

[1989AllPro]

Just bought an astro 3 weeks ago, ran fine to and from work a few times. one morning, it refused to start. I dropped the tank, removed the fuel pump, drained all gasoline, and cleared it from the fuel lines, i checked the fuel pressure at engine, and all checked out. I reinstalled the pump into the tank, and continued my diagnosing. After i reinstalled the tank, i checked both fuse boxes, and cleaned all the terminals and fuses. I removed, cleaned, and reinstalled all grounds on the vehicle i could find (including the ones beneath the vehicle and between the engine and firewall. all checked out. I checked the ignition system from battery to plugs. All was well. ***Note*** I installed a new key lock cylinder the day before it refused to crank. When i would turn the key to the on position to crank, the security light would stay on for a while longer than the other hud lights, along with the battery indicator light. After trying to crank it to no avail about 15 times, the battery died. Needless to say, i replaced it. Whenever i installed the new battery, the security light went to blinkin*g. Well, i tried to do the "gm passlock relearn procedure" by doing the 3-10 minute "key on" cycles. after the third time, the security light went solid and will not crank for anything. ***Note**** After installing the new battery, it cranked and died 3 times, while doing the relearn. ANY HELP IS APPRECIATED!! Please HELP!!!!!

[Leeann_93]

Are you sure you performed the Passlock relearn procedure properly? It MUST be followed exactly.

[1989AllPro]

I will try again today here in about an HR or so.

[1989AllPro]

Does it matter whether or not the doors are open?

[Leeann_93]

No idea, but I don’t think so. First time on my ‘99, doors were closed. Cannot remember if doors were open or closed on the ‘05. I have dome override engaged, so no interior lights.

Make sure your battery is fully charged.

[1989AllPro]

Ok...so last night I pulled the battery, and bridges the two terminals on the electrical leads (to clear any ambient electricity in the circuits and capacitors, and this morning I did the procedure...it worked to remove the security light, but it still won't start. I am getting spark, and fuel pressure is good [I haven't checked with guage today, but have no reason to believe it is any different than 3 days ago]. Could the injector pulse still be disrupted with no security light on???

[Rod's Trucks]

1989allpro,
I do not know if this might help, but....
When my '98 with 212K miles quit 'starting'; it would crank just fine, and occasionally fire once when I released the key. After a lot of diagnostic effort, I decided it 'might' be the ignition security system. My original key was badly worn, so I took the VIN number and registration papers to the dealer. The dealer made me a brand new key, from the factory code for only $10.
It was the best $10 I've spent on the van. I have not had any issue since then. I had a copy made of the new key, and tossed the old ones. It has never given me a problem since.
My '98 had about 212k on the odometer at that time.
I would recommend everyone with a higher mileage vehicle consider getting a new key made from the original code, before the tumblers in the lock get badly worn. This would be particularly important if your daily key is a copy of a copy.
Rod J

[1989AllPro]

What if I've already replaced the key lock cylinder?

[Huckleberry]

I have a 2000 Saturn SC1 that had PassLock issues after a lock cylinder replacement.
I managed to get it resolved with the three-ten-minute-cycles-method,
but more importantly, I learned that I won't ever buy another vehicle with PassLock.

[Astrofarian]

I also had a '98 that would actually do this intermittently; finally popped the top cover off of the steering column shroud and re-seated the little sensor-thingy over the lock cylinder. Smooth sailing from there.
Go back and re-do the 3-10 minute relearn procedure and NO, it makes no difference if the door is open or not. Maybe hook your charger to the battery just to be safe...the re-learn has been known to draw a lot of power out of the system and we all know that computerized circuitry does NOT play well when deprived of its power requirements.
-M!ke-

[Wiley]

delete

[Rod's Trucks]

1989allpro,
You wrote "What if I've already replaced the key lock cylinder?"
In my case the problem was a VERY BADLY worn key.
Replacing the key with a brand new factory cut key, cut from the original code, was the solution ...$10 at the local dealer.
YMMV.
Rod

[1989AllPro]

I appreciate everyone who weighs in on this, BUT the factory key copy is implausible because the ridges are worn so badly on the key, and the lock cylinder itself is worn from so much wiggling and violent key jarring...so it is what it is with the new key. As far as the relearn process goes...I may try it again when I have time...I actually disassembled the front dash and I can't for the life of me, locate the passlock module...does anyone have any experience with the issue before and read a code of p1351 (IGN voltage too high)? Or what to do after the key lock cylinder has been replaced, and is irreversible?

[Leeann_93]

Passlock module is in the housing the key cylinder mounts to.

Pics and stuff on this page (about halfway down) for my '99:
https://www.astrosafari.com/viewtopic.p ... &start=280

I had to replace the ignition switch, key cylinder and the module they mount to in order to get the '99 back on the road. It was a beeeeyotch, but I got it.

[1989AllPro]

That is for a 99, no?

[1989AllPro]

What were your symptoms????

[Leeann_93]

What were your symptoms????

No run. At all.

[1989AllPro]

Leeanne, great info!!! Thank you!!!! I will review my method

[1989AllPro]

Those plastic gears, are they for an ignition circuit or what?

[Leeann_93]

The key cylinder and ignition switch (electrical portion) both mount to the housing with the plastic gears. When you turn the key, the plastic gears turn, turning the shaft that the ignition switch mounts onto. The slop on the plastic gears was really bad on my '99; if I turned them by hand, I could get it to start (barely) but the key cylinder wouldn't turn them far enough. As it turned out, the key cylinder also was bad. I had to replace all 3 components for mine to start and run like it should.