How will I know if the ecm needs to be replaced on my 2007 Sport Trac? The wrench light comes on, my speedometer isn't working, my dummy lights on the dash come on and off randomly, my milage and trip meters wont register. When I start my truck all lights are off until I start driving then the wrench comes on then the others do their thing of coming on. It seems to go into limp mode once the wrench comes on. The MAS and the TPS have been replaced. I took it to a local garage and they hooked it up and scanned codes. They tell me it is definitely an electrical issue and not mechanical.