2002 town and country will not start intermittently. Been checked out at garage. Say they cannot find anything. Most times when try to start all warning lights come on.

Will not start how intermittently ? The engine won't turn over or engine does turn but won't start . Starter relay , lose connection . Checking power an grounds would be the first place to start , voltage drop test the main electrical circuits . Voltage Drop Testing the Starter

The starter circuit control is achieved by the starter motor relay ! It is located in the under hood fuse/ relay box or as Chrysler calls it ,integrated power module ! If you pull out the relay an look on the bottom where the pins stick out you will see four sets of numbers .30,87 an 85,86 ! 30 is B+ voltage . 87 is to the starter solenoid . If you jumped those two spots where the relay plugs into the starter would crank the engine over . The last two 85 an 86 are the control side .If you checked with a volt meter where 86 plugged into ,with key on it would show B+ voltage . The last pin is from the PCM - engine computer . When turning the key to start a signal is sent to the PCM to let it know crank has been requested , in return the PCM supplies a ground to pin 85 energizing the starter motor relay sending B+ voltage to the starter motor cranking over the engine . Here is another video on test from the relay base (where relay plugs into ) This is for a horn circuit but same thing . VEHICLE RELAYS Testing from the relay base The relay could be going bad , you never know .Replacing the relay mite not be a bad idea . Good luck , hope this helps !

If the lights don't come on and you have a no start. Replace the ignition switch.