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Q: Car shuts off when trying to start.

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My car went into anti left lock when i attempted to start it. It has done this previously so i knew the drill (so i thought). I unplugged the battery for 30 minutes hooked it up. I turn the key to the acc/on all the running lights headlight windshield wipers all the dash light are on. The dash does the bulb check everything is per usual and then yoi turn the key forward into start with the clutch pressed to the floor everything shuts off. When you release the the key back to acc/on position everything lights back up. I work at a parts store and am very handy when it comes to car. Always done all the work to my cars so i checked the battery with a new one checked all connections every single fuse has been pulled and inspected the relays have been checked one by one with a brand new one. I currently have both the ecm and the bcm main lines unplugged to do sort of rest possibly idk at this pointive done atleast 20 hrs of research and ask numers people. Please can you help me?

My car has 95000 miles.
My car has a manual transmission.

Your key is a transponder key. The transponder in the key works together with the theft deterrent module that is attached to the ignition lock cylinder. The only good way to test this system is with a shop level scanner such as what Snap On sells. Whatever scanner you use must be able to communicate with the BCM in order to receive data about the alarm system. The module on the ignition lock cylinder can develop intermittent connections.

Something else to consider is as follows. The anti-theft system relies heavily on the position of the door locks and door switches to know the state of your car. Testing this can be very simple. With the key on, begin with all the doors closed and open and close them one at a time. Watch the door ajar light on the dash to see if it turns on when each door is opened. Be sure to close each door after you open it. In addition, if the light is on with all the doors closed, you know there is a problem with the door ajar system. If this is the case, you will need a scanner to pinpoint which switch is the problem. Keep in mind the anti-theft module also monitors the trunk lid.

As for resetting the alarm when it goes off, there are three ways to do this that I know of. The first is fairly obvious, use the key fob. The next method is similar to what you have already attempted. Disconnect the battery, turn the key to the run position and reconnect the battery with the key in the run position. If that doesn’t work, use the key to lock and unlock the doors three times in a row, including the trunk lid, one at a time until one of them resets the alarm. I have had luck with the last two on almost every car.

Of course that is just to reset the alarm. If the door switch and lock system all check out good, meaning you have checked their operation with a scanner, I would be looking for codes in the anti-theft module.

If you need further assistance with this, I recommend contacting customer service to see if there is a technician in your area with the tools to address your issue.

1-844-249-6752 · hi@yourmechanic.com

Good luck!

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