My 1999 LS400 ECU will not communicate with diagnostic readers. I have replaced all ECU capacitors and a couple of resistors without any success. Four different auto electricians have connected various devices both to the engine bay port and the under dash OBD2 port without a result.
One theory is that Toyota used a modified code for non US Lexus sedans around 1999 which only allows Toyota readers of that period to talk to it. Apparently in 2000 they reverted to standard OBD2 protocol again.
Anyone else having the same problem or found a work around?
Gabriel O.
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