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aaronandchris
12-31-2007, 07:26 PM
I have a 2000 Grand AM GT, 135,000 miles. Woke up yesterday morning and the car will turn over, but will not start. The ignition turns fine, and when positioned to "on" the security light does go off, the fuel pump sounds "normal" (fuel filter changed about 5,000 miles ago) and the car does not throw any codes. What should I look for? The car worked great the day before. Battery is stronger than ever. Everything appears normal except no fire. I will test for a spark tomorrow. Can it still be Passlock related if the security light shuts off?


I am thinking it could be anything: ignition module? coil pack related? fuse? Passlock? sensor? fuel pump? Without a thrown code, anything specific to test?

Any suggestions would be great!

aaronandchris
01-03-2008, 06:03 PM
I checked the wires for spark and it appears to be fine. After turning the key to on a few times, and hearing the fuel pump, I checked for pressure on the fuel rail and did not have much. I believe it is fuel related, which could also mean the Passlock is causing the problem. I changed the fuel pressure regulator six months ago. I will try to check the fuel pump the best I can. I have had the Passlock activate in the past (last time around September) and usually the light flashes when activated. The light shuts off after a few seconds when turned to the on position. Does this mean it is working? I appreciate any suggestions.

SSRacer
01-03-2008, 06:10 PM
Chech the cheap stuff first, like the fule filter. Had the passlock screw up mine before though. Sucked a$$.

aaronandchris
02-06-2008, 08:12 PM
I wanted to provide an update: After checking for spark and fuel I determined that it was the fuel pump. I changed the fuel pump a week ago and it started up the first try and is running like a champ.

nickofcourse
02-06-2008, 09:23 PM
cool, great you got it fixed. have fun driving.

DoCDooM
03-02-2008, 10:53 AM
WARNING!

Long drawn out answer to your woes below!

Ok Everyone,

Here is the lowdown on the GM PassLock III system found in my 2002 Grand Am GT

The PassKey system used a RF ID chip embedded in the key, the PassLock system uses a regular key.

Purchase a new key anywhere, at the dealership the blank for a Pontiac is $16 CAD, the Chevy key is exactly the same with a Chevy symbol on it and costs $6 CAD. (That’s cause Pontiacs are FANCIER) lol

The Ignition key cylinder has a Hall Effect sensor in it, which can only be replaced by replacing the cylinder.

A Hall Effect sensor is a semiconductor device that detects and measures magnetic fields.

The moving part of the key cylinder has a “coded” magnet on it, which passes by the Hall Effect sensor when the key is turned.

The “coded” magnet is a small ceramic slug with several rows of opposing magnets all in once piece, think of a metal UPS bar code.

The idea here is not to have one and only one key that will start your car but to ensure that the key cylinder has actually turned in order to start the car.

When the key is turned the Hall sensor detects they turning of the cylinder and then effectively closes a relay which connects a resistor to the security system (everything from that point on is the same as PassKey II, the one with a resistor slug in the key itself)

Current remote starter bypass kits allow the car to start by putting the resistor in place in that circuit but the security system indicator on the dash still lights up until the key cylinder is actually turned.

The magnet in the key cylinder should normally last about 1200 years before it starts to lose its magnetic charge so that is never the issue unless you have been hitting your keyhole with a hammer.

The Hall Effect sensor on the other hand, is a Hall Effect sensor and as such is prone to failure by its nature.

This is basically a transistor whose gate is actuated by a magnetic field, these devices have been around since the early days of semiconductors and while they have increased in complexity and flexibility over the years the chemical makeup of the sensor is essentially the same.

The chemical bonding of the transistor breaks down over time and exposure to the very magnetic field it is monitoring.

Once the Hall Effect sensor starts failing you get the “car wont crank and I have to re-learn” problem or your “Security” light comes on while you are driving etc. etc.

When you “Learn” your key you are actually making the computer read the magnetic field in the cylinder through the Hall Effect sensor.

The one and only solution is to replace the ignition cylinder assembly, only available at the dealership and they will code the mechanical tumblers to your key as part of the sale.

All in all this cost me $371.00 CAD at the dealership yesterday, I changed the cylinder out myself in about 5 minutes, then you run the “Learn” procedure (11 minutes in ON position until security light stops flashing)

Remove centre console bezel, remove the radio, stick an Allen key into the retaining key under the cylinder (near the back and no you cant see it but if you look at the new cylinder you can figure it out, I did it blind without instructions on the first shot)

The new Ignition cylinder should last several years.

I also found that my old cylinder had quite a bit of sloppiness (lateral or sideways movement) visible once I replaced it.

This mechanical “looseness” could also contribute to the Hall sensor not getting the right info, so the issue may very well not be the sensor but just generally bad alignment between the sensor and the magnet.

Directly measuring magnetic fields with a Hall device is fairly tricky business and a loose cylinder could easily cause this kind of problem.

As evidence to this statement I found that my security light would come on while driving after I hit a bump or turned sharply, the keys swinging in the ignition would cause the cylinder to move around, likely fouling up the magnet to Hall sensor alignment.

The Hall Effect sensor on my old cylinder had evidence of overheating, the plastic case was crazed and had a heat mark on it so I suspect that it had problems regardless of the above speculation.

Anyhoo, that’s the problem and the fix, if you are having these problems get Ye to a dealership and cough up the cash before you get stranded.

The guys at Stampede Pontiac GMC in Calgary Alberta were great, very accommodating and took care of re-coding the cylinder to my key right in front of me, so now I know how to do that too.

Cheers All

Dan


I have a 2000 Grand AM GT, 135,000 miles. Woke up yesterday morning and the car will turn over, but will not start. The ignition turns fine, and when positioned to "on" the security light does go off, the fuel pump sounds "normal" (fuel filter changed about 5,000 miles ago) and the car does not throw any codes. What should I look for? The car worked great the day before. Battery is stronger than ever. Everything appears normal except no fire. I will test for a spark tomorrow. Can it still be Passlock related if the security light shuts off?


I am thinking it could be anything: ignition module? coil pack related? fuse? Passlock? sensor? fuel pump? Without a thrown code, anything specific to test?

Any suggestions would be great!

Sherwood
03-04-2008, 02:55 PM
Thanks for the great read there DocDoom. My security light is coming on with out a remote starter and I'm afraid that I will be stranded at the worst time possible. Thanks again.