deoilboy

When I start the engine on my 2000 silverado 1500. It starts right up and about 3-5 Secs later it shuts down. I tried giving it fuel but that doesn't help. We checked for fuel and spark and they are both good. The security light starts flashing when it shuts off. We took it to the garage and they said it was the masslock sensor and the ignition. Any suggestions on what it could be other than that?
Thanks

jackyshaikh

How your truck went in theft mode?
Did you use wrong key or have you cut new key outside?
why in outside garage they wants to change passlock sensor and ignition,how they found these two things need to change?

shawnvw

try turning the key to the on position(do not start) for about 10 minutes or untill the light stops flashing. Then turn the key off and try to start it.

ukrkoz

sounds like your passlock system decided to kick in. sorry, bro, i do not envy you. it's total pain in *** to deal with. dealer will eat you to the bone to reset it. search the forum, i had passlock reset procedure posted while back here.
actually:

Re: 03 Silverado passlock/igntion issues[/b] [/align][hr]

stand next to your vehicle; press and hold lock/unlock buttons simultaneously for 7 seconds. locks should cycle. that resets the fob/locks.as of the passlock situation, call dealer and find the right protocol for passlock reset. i had it posted somwhere about 3 mths ago, but forgot which forum it was in.ok, i got you covered, bud:Here is the procedure.Turn ON the ignition, with the engine OFF. Attempt to start the engine, then release the key to ON, vehicle will not start. Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF. Turn OFF the ignition, and wait 5 seconds. Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes, the vehicle is now ready to relearn the PasslockTM Sensor Data Code and/or passwords on the next transition from OFF to CRANK. Important: [/b]The vehicle learns the PasslockTM Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle. Start the engine, the vehicle has now learned the PasslockTM Sensor Data Code and/or password. With a scan , clear any DTCs if needed, DTCs will self clear after 100 ignition cycles CREDIT DAVE NOVA. ALSO, I THINK, MODS COULD PUT IT A STICKY FOR THE FUTURE REFERNCE HERE. IT'S QUITE COMMON SITUATION.[/align][/align][/align]or:[/align][/align][/align][/align]or try thisi see sticky again!!)Yep. Turn the ignition to on. Your security or theft light should be flashing. This is "long tamper mode". Leave in the on position for 10 mins. and the light should turn on steady. You have reset the passlock system. If you are looking to "disconnect" your passlock, here is a modification that will work. There is no need to install the remote starter. PASSLOCK I or II DISABLEMENT[/b] The following is a procedure to disable Passlock I or II Systems for vehicles in which remote start/stop system installations are required. This procedure is required because a remote start system will not function with the current Theft Deterrent System (Passlock) which is included on many 1996 and up GM vehicles. Please note that this modification is intended to be used only in conjunction with the installation of a remote start/stop system and does not provide a procedure to install a remote start/stop system. CAUSE If an attempt is made to start a vehicle by a means other than a key rotation in the ignition switch, the Body Control Module (BCM) will interpret this start as a vehicle theft and disable the fuel injectors. CORRECTION A minor wiring modification may be made to allow the vehicle to be started remotely. This modification includes adding a switch to allow the customer to select “ON” to disable Passlock or “OFF” for normal Passlock operation.[/b] CAUTION: When this modification is performed and the switch is set to the ON position, the theft deterrent feature will be disabled. When the theft deterrent is disabled the SECURITY or THEFT telltale will light up indicating that the theft deterrent system is NOT functioning.[/b] PASSLOCK MODIFICATION Refer to appropriate GM service manuals and/or SVMQP Electrical Guideline Manual for instruction on splicing and electrical connections. 1. Select a suitable on-off switch (see note below) which will be used to disable/ enable the Passlock System. Mount the switch in a location such that it is accessible to the driver and will not interfere with normal vehicle operation. NOTE: This is an extremely low current circuit (approx. 7mA), it is therefore very important that a high quality, low energy, fast acting switch be utilized for this application. 2. Turn the ignition switch to the OFF position. 3. Locate the Main Ignition Switch Harness. GM's Passlock System wires exit the Ignition Switch Tumbler together and then join with the Main Ignition Switch Harness. (See http://www.bulldogsecurity.com/ or http://64.85.6.118/diagrams/diagrams.asp and select your Make, Model and Year for wire colors and clues on the quickest way to access these wires.) 4. Locate the Yellow Passlock Data Wire which is included in a bundle of three tiny (20 GA) wires wrapped in friction tape. Cut this wire and splice a 0.5mm2 (20 GA) yellow wire to each end of the cut wire. Keep wire length to a minimum. Route modification wires clear of moving parts. Connect the yellow wires to the switch such that the contacts are OPEN when the switch is in the ON position. 5. Turn modification switch to the OFF postion (contacts closed). 6. Start vehicle to verify normal operation. If engine “cranks but will not start" recheck the switch position (contacts should be closed), wire connectors and modification wiring. SWITCH OPERATION[/b] To enable remote start: Start the engine with the ignition key (modification switch must be in the OFF position). Turn modification switch to the ON position (contacts open). The SECURITY or THEFT telltale will light up indicating that the Passlock System is inoperative.[/b] Once the SECURITY or THEFT telltale has been on for at least 5 seconds the vehicle can be turned off and then remotely started. To disable remote start: The Passlock System can be reactivated by turning the modification switch OFF (contacts closed). [/b]Vehicle can either be running or off when this is done. Please note that the VCM/PCM will record Diagnostic Trouble Codes (DTCs) related to the security system when the modification switch is in the ON position (circuit open). This is due to the way that the VCM/PCM interprets this condition. NOTICE Any condition which removes battery power from the Vehicle Control Module/Powertrain Control Module (VCM/PCM) (e.g. dead battery, disconnected harness connectors, etc.) will prevent the vehicle from being restarted. If the engine exhibits a “cranks but will not start” symptom, place the modification switch in the OFF (contacts closed) position. This will reactivate the Passlock System and allow the vehicle to be started with the ignition key.[/b] Ray[/align][/align]