I've got a 99 3.9L, I'm getting a brake light along with a ABS light on my dash display. I'm trying to get the error code from the comp to lead me in the right direction. I suspect the speed sensor, but I'm not positive. Anyway, I've read that I could get the fault codes by pushing the odometer reset button in and then turn the ignition key to run/on and it should display the code. I've also tried another method of truning the key from off to run/on a number of times. And finally I read in a manual that I should ground the RWAL CAB diagnostic connector and count the number of flashes on the indicator lamp. It dosent however, tell me where the unit is located nor which lamp to watch flash...ie. brake light, ABS light.......? I don't want to buy a diagonistic comp. Any help or info would be great..THX.