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Hi, my name is***** you give me a little more information? What is the background on this problem? Does the motor crank but not start?
Sorry about the wait I had to step away
It sounds like the starter battery under the hood is bad
The battery in the trunk could also cause the problem but it is more likely to be a bad starter battery. Both batteries should be tested. Jump starting is only done at the battery under the hood.
If a jump start from the battery under the hood did not help the battery in the trunk should be tested. It's also possible that there is a fault with the starter or with the transmission gear selector module. If the computer does not realize that the transmission is in park it will not activate the starter.
A jumper can be connected to the rear battery as long as the front battery is ok. You can connect jumpers to both to be sure. If you are comfortable with the vehicle electronics you can remove the starter relay and bypass the relay with a jumper lead to test the starter motor.
Click on the attachment below.
You will need to remove the green relay and place a fused jumper lead from terminal 30 to 87 in the relay connector in place of the relay. When you make your connection the starter should operate.
If the starter works it indicates a fault with the battery, cable connections or with the start authorization system that involves the computer and relay.