I am guessing the vehicle is equiped with ABS. If so disconnect the ABS unit and carefully try hooking the battery up again. I am betting the ABS unit is shorting out. I hope this help. If you have anymore questions please email us again. Thank you
can you try to unplug the ABS unit? You may be getting power to the unit from more then one spot. Also have you had anyother work done to the van? Could somebody moved a harness or have it pinched against the brake lines. And also unplug the brake fluid level sensor at the mastercylinder. If you have anymore questions please email us again. Thanks.