Does it have an aftermarket remote start? If so that may be what they are talking about. Any loose wiring under the dash, splices etc? Did you check the ground to the control module?
Check DC voltage between neg battery terminal and each ground while running. As previously stated the alt could also cause problems. Especially if it has a bad battery, under a load from bad wiring bad fusible link etc. Does the link (small cable from the the alt) Get extremely hot? Alt get very hot? If you can read voltage (>0.1 or 100mV) between the lug on the alt and pos battery cable I would disconnect the alternator see what happens. Be sure to unplug the connector and the ring terminal and have the terminal insulated. If you replace the alt be sure to check the fusible link and connections as it may overload the new alt and need to be replaced as well.
Check DC voltage between neg battery terminal and each ground while running. As previously stated the alt could also cause problems. Especially if it has a bad battery, under a load from bad wiring bad fusible link etc. Does the link (small cable from the the alt) Get extremely hot? Alt get very hot? If you can read voltage (>0.1 or 100mV) between the lug on the alt and pos battery cable I would disconnect the alternator see what happens. Be sure to unplug the connector and the ring terminal and have the terminal insulated. If you replace the alt be sure to check the fusible link and connections as it may overload the new alt and need to be replaced as well.
