I recently bought a GQ-4X and I canīt read the EEPROM S95040 on a 2005 Toyota ECU. When I try to read it, it appears in blank. And when I try to write it appears an Error message. I am testing a 3M SOIC8 testclip. I prepare the cable and check all the connections and are ok.
Programming a chip in circuit is tricky. That because the successful rate is depending on the circuit of the EEPROM chip. In most of case, the programmer has no enough power for your ECU module. So, the possible way of programming chip in circuit is to power the ECU module by a external power. Then only connect the signal and ground line to the chip with programmer.