Hello, I have been developing my software for the KL interface, however I am getting inconsistent results.

Sometimes I get a response of 0x55, 0x01,0x8A which is good,

but sometimes the car responds with, 0x68, 0x6A, 0xF1, then the communication fails.

Does anyone have any suggestions what could be causing the problem.

After a bit more investigation I have found a solution, I am running both the KL interface and an ELM323 in parallel.

Before switching to the KL interface I issue the ELM323 with a "ATMA" command to go into listen only mode, however this seems to be the problem. Tonight I issued a reset "ATZ" to the ELM323 rather than the "ATMA" comand before switching to the KL and the response from the car is correct every time. Since I don't have a storage scope its tricky to see exactly what was going on.

Over the week end I hope to finally read some live data, slooowwww progress!