ALDL not working - 2005 Mazda B3000 Cab

Check your aldl fuse. There is a chance that if the fuse is blown and you are not getting power to the aldl, then you are not getting power to the ECU.

THE COMPUTER CONTROLS ALDL READOUTS

You have a defective battery.

Yes. Or one of the circuits back to the computer.
Even tho you have driven 200 miles the drive must include several things including stop-n-go and various speeds to be ready for a test.
You should be able to connect a scanner to the connector and read the current data flow from the sensors even if the system is not ready for a test.

General motors likes to run the power source to ALDL connector plug through the cig lighter fuse or the asscerory lighting fuse . you need to check these fuse and make sure they are good . if they are not replace the fuse and see if your code reader work . If the fuse are all good then you will have to check the power circuit the feeds the AlDL connector for a short or and open

with a test light test the ALDL plug for battery power the pin right next to it willl be ground. ( hook the test light to power and a ground will light the light) the check engine light should come on and if you crossthe upper two pins in the aldl the check engine light should flash out the codes. The code reader might not be working and may need to hook it to a different car and see if it reads a different car.

check the fuse for the accessory power port or the cig lighter

if its not under hood, check under dash on drivers side!!

CHECK THE CIGAR LIGHTER FUSE, THAT POWERS THE ALDL.

glad you got it fixed