Hi all , we have a Hyster H2.5XT A380B , 2017 , lpg 2.4L PSI engine , we have just the replaced the head gasket and upon trying to start we get code 628, this relates to fuel pump relay coil open ? as soon as we connect the battery the previously mentioned relay powers up , the engine turns over but we have no spark, we have checked over the wiring /connectors etc and everything seems ok , any help on this would greatly appreciated