I recently got back from a trip and went to start the pickup and it would start but then die a second later. i swaped some relays around left the key on an tried it again and that time it started up and ran fine real smooth. but know I have no gauges except the tack an the battery is not charging. also my scan tool will not read any codes if it has any it just says "attempting to communicate with the vehicle" any help would be great thatnks