I played a few hours with my bad R270 programmer, and I succeeded to make it erase 35080V6/VP in a few minutes.
First I changed 7805 with L7805CV, before voltage was 4.94V, after that was 5.02V, but nothing happened, still can’t erase more than hour.
after that I started to play with 35080 PCB, and in the end started to erase 35080V6/VP after 74HC125 changed with 74HCT125M, erase 5-10min tried on 3 chips, maybe if I change 74HC00 will be better, but I haven’t one for try.
A good tip may be helpful- M35080 V/VP not read/erase:
1- Change the power supply to good quality: 12V 1.5A !
2- Change capacitor :
But things are different from another R270 from other folks in a forum. The boy did nothing on the PCB and got on well with his R270 programmer. The site he put there: http://www.obd2diy.fr/wholesale/r270-v120-cas4-bdm-programmer-629.html
The last: if you’re reading the post and wanna buy a “R70 programmer ebay”, forget it!!!!! Go to a reliable OBD tool shop with professional tech support! But attention please to china clone; some also are not good to trust in. Good luck!