i believe i need a new windshield wiper pulse module because only on low or high

What is your question?

my wipers work on the regular settings but not on pulse. this is why i think i need a new module. unfortunatley the van wiper motor is different from the gm pickup trucks with the famous pulse board problem so i cant simply replace board. any ideas?

What makes this problem better or worse?

nothing

How long has your 1990 GMC G3500 had this problem?

6 months