I just picked up a new scanner, made by Strategic Ind. Thought I'd try It out today. Question... what obd protocol should I use when manually selecting a protocol? I get a connection error if I try J1850PWM. I can use ISO 9141 but... it trys to display fuel trims for B1, B2, B3, and B4??? Now, the last time I looked, I don't have a W 16 in my '03 xk8... I know it must be a protocol thing. BTW, fuel trims for B1 and B2 are fine, lt and st. the trims for B3 and B4 are a lot higher... it seem odd to me,
Should'nt I just see stft and ltft for only B1 and B2 ?... 4 numbers?
Also, could it do any harm if the wrong protocol is tried ? I tried to contact strategic but, they could not answer my question.


Thanks to all who reply, I'll keep researching in the mean time.

 

When I first connected my Ultragauge, I did not select a protocol and after a few days the car started displaying gearbox error and went into limp mode. Forcing the ISO 9141 protocol solved the problem. You will probably have similar trouble.

 

Thanks RJ237, I guess I'll just deal with, and use ISO9141. I guess I can just ignore the B3 and B4 fuel trim data... I can't help but wonder why this is though. FWIW, the car Runs GREAT! ... no codes... last 3 years.