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Q: Cranks but won't start

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Truck just shut off no warning no nothing im told it could be auto shut down relay how do I confirm that I tried using a decoder but being told the vehicle must start also need to know if I should just buy the computer or try eliminating the sensors.

My car has 180000 miles.
My car has an automatic transmission.

This may happen for many reasons. There are in fact modes in your truck’s computer that will trigger the ECU to shut the engine down in the event of some kind of failure that may cause major damage. This is a fail safe measure that is taken by the ECU when it detects critical components that may be not functioning properly or something that could jeopardize the safety of passengers or the engine.

Without power to the ECU itself, it my be difficult to use a scanner, however this can be bypassed, but does take a bit of skill. I would suggest having an expert from YourMechanic come to your home to diagnose your no power issue.

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Hello, thanks for writing in about your Dodge Ram 1500. I’m curious if your Check Engine light on. Checking the basics will help here: will it crank but not start? If so, is there spark at the plugs and does spritzing some starter fluid result in a brief engine start? Check fuel pump and ignition fuses and relays - a hard shut-down was a clear failure of some kind.

If you need help with this issue, I would recommend having your no start condition inspected by a certified technician, such as one from YourMechanic, to diagnose this problem, get an accurate assessment of damage and cost estimate for repairs. YourMechanic can dispatch a mobile, professional mechanic to your location for this repair.

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