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Whitetail Crazy · 05-07-2008, 08:12 AM

So here is what I have done. I had hauled the car to my house to work on it rather than going to where it was at every night after work. I took the locking piece out from the old key and tumbler set that keeps the cylinder in place (normally the key must be in a certain position to release the cylinder) just in case the key locked up again and would not turn I could now pull the cylinder out at any time. I run the whole reset/reprogramming thing on the old key/cylinder. It works this time and when the key will turn, it starts and there are no security lights. I take the old key and cylinder out and put the new one in. The car starts but the security light is on steady. Stick the old one back in and it still starts with no security light. There are 3 wires (black, white and yellow) going to the passlock sensor, I cut the yellow and hook one end of my OHM meter to the yellow end coming from the cylinder and pierce the black wire with the other end for the OHM meter. At this point the car will still start but has the security light on and will not give me a constant reading so I put the car in reverse (won't start in reverse) and turn the key to the start position and hold it there. The meter slowly climbs to a steady .887K of resistance. I mention the slow climb because when the car was starting it would crank longer than I would expect before starting, in fact it cranked for about the same time it would take for the reading to settle. I do not know that much about resistors, normally if I need a resistor I just go to radio shack and find the one closest to my reading. The problem that I ran into is that they did not have anything that matched what I was looking for. So I buy an assortment of resistors for $12. There are literally hundreds in this bag. I plan on experimenting with resistors in series and twisting two together and such to get the correct resistance. I learn that by twisting two together you get roughly half the advertised resistance (some or many probably already know that but I did not). After testing numerous resistors with the meter I find one that reads 1.7??K, I twist two of those together and get a reading of .879K, close enough to the .887K a was looking for. So I strip some of the coating off of the black wire, not breaking it's connection to the cylinder. I hook one end of the resistors to the stripped section of black and the other end to the previously cut yellow wire (end going to the BCM this time, tape off end to cylinder). I solder these connections and tape everything. Now with new key and cylinder it starts immediately and there are no security lights.
All of the searching that I had done shows that the passlock system is a known problem on these cars, leaving people stranded until the 1/2 hour key reprogramming is done. This could be something that could be done to avoid that problem in the future.

05-07-2008, 08:12 AM	#4 (permalink)
Whitetail Crazy Registered User Join Date: Apr 2008 Location: Illinois Posts: 29 OS: windows xp	Re: 2002 Impala won't crank So here is what I have done. I had hauled the car to my house to work on it rather than going to where it was at every night after work. I took the locking piece out from the old key and tumbler set that keeps the cylinder in place (normally the key must be in a certain position to release the cylinder) just in case the key locked up again and would not turn I could now pull the cylinder out at any time. I run the whole reset/reprogramming thing on the old key/cylinder. It works this time and when the key will turn, it starts and there are no security lights. I take the old key and cylinder out and put the new one in. The car starts but the security light is on steady. Stick the old one back in and it still starts with no security light. There are 3 wires (black, white and yellow) going to the passlock sensor, I cut the yellow and hook one end of my OHM meter to the yellow end coming from the cylinder and pierce the black wire with the other end for the OHM meter. At this point the car will still start but has the security light on and will not give me a constant reading so I put the car in reverse (won't start in reverse) and turn the key to the start position and hold it there. The meter slowly climbs to a steady .887K of resistance. I mention the slow climb because when the car was starting it would crank longer than I would expect before starting, in fact it cranked for about the same time it would take for the reading to settle. I do not know that much about resistors, normally if I need a resistor I just go to radio shack and find the one closest to my reading. The problem that I ran into is that they did not have anything that matched what I was looking for. So I buy an assortment of resistors for $12. There are literally hundreds in this bag. I plan on experimenting with resistors in series and twisting two together and such to get the correct resistance. I learn that by twisting two together you get roughly half the advertised resistance (some or many probably already know that but I did not). After testing numerous resistors with the meter I find one that reads 1.7??K, I twist two of those together and get a reading of .879K, close enough to the .887K a was looking for. So I strip some of the coating off of the black wire, not breaking it's connection to the cylinder. I hook one end of the resistors to the stripped section of black and the other end to the previously cut yellow wire (end going to the BCM this time, tape off end to cylinder). I solder these connections and tape everything. Now with new key and cylinder it starts immediately and there are no security lights. All of the searching that I had done shows that the passlock system is a known problem on these cars, leaving people stranded until the 1/2 hour key reprogramming is done. This could be something that could be done to avoid that problem in the future.