we have seen several 129's of that vintage with similar issues, something in the module burns out when you jump start the car. the only fix was to replce the entire module. i cannot say for certain that this is your problem, just what i have seen more than once in the past. ther is a company that can rebuild them, they reprogram them to eliminate the "defect". i have used them many times and am very happy with their products. send them an email with your problem they may be able to offer you more info than i did.

http://www.beckmanntechnologies.com/products.html