Dodge Repair/'98 ram: vehicle theft security system
QUESTION: i have a dodge ram 1500 that will not stay running, alternator checks out good tookin too oriellys working fine . after disconnecting the battery truck dies. while truck is running gauges bounce and the seat belt light flashes and the security light is the only indicator light that comes on when starting
ANSWER: Hi Bill,
What is the year and engine size (L) of the vehicle?
When you went to O'Reilly's did they do a fault code readout and did the tell you any fault code numbers?
When you say will not stay running, do you mean that it starts but dies in a couple of seconds?
That would be the behavior if your vehicle theft security system has not been disarmed. Try the passenger side door lock using the key to lock, then unlock the door. See if the security light is then "out" and it will start and run.
Otherwise tell me what you mean by 'not stay running'.
Please read the PS (below) and respond to it.
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QUESTION: I tried both door locks because I thought I was the security system but that didn't work. Is there any other way that the security system could be overridden?
ANSWER: Tell me the year model.
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QUESTION: 1998. We believe it might have an aftermarket security system.
I can only speak to the Chrysler security systems which typically show that they are 'armed' by either the status light being 'on' steadily, and then when you try to start it the engine will catch and run for a couple of seconds and then shut down. The typical disarm is to unlock a locked front door using the key or a key fob. Basically there is white/dark green wire from the driver door lock to the body control module which when you unlock the door inserts a 660 ohm resistor between the wire and ground momentarily which then disarms the system. If that wire in both front doors 'opens' (the similar wire on the passenger door is white/light green) then the key no longer disarms it. So you then go to the body control module usually located on the back side of the fuse box on the end of the dash and find one or the other of those door wires and ground it with a 660 ohm resistor momentarily at the plug of the bcm. That is the only way I know to get around and armed system. Once you disarm it then you have to just never arm it again by always securing the vehicle locks by the hand-operated push button locks on the doors, never ever using the power door locks to set up the doors to lock as that action also arms the system.
Now if you have an aftermarket I don't know whether it is set up similarly or not. I don't have the wiring diagrams for the '90's trucks so can't be certain but I have described the system as used in the cars of that vintage. If you have a bcm then it is not easy to detach the theft system from operation entirely as it is part of the bcm.
Be sure that the 'no run' appears to be the security system, of course.
Thanks for the rating and nomination which you are welcome to do both again.