I have a 2001 Mazda Tribute 2WD. I've been pulling my hair out with electric problems. Here we go: I got it and replaced the fuel pump and alternator. It starts and runs fantastic. When the vehicle is off, the battery has 12.45 volts. I start the car and the voltage at the battery drops to 11.26 volts. Doing an amp draw test at the engine compartment fuse box I have a 6.28 amp draw at the EEC fuse. I also have a .94 amp draw at the BTN2 fuse. I did find a short under the dash on the "Room" fuse circuit. (It is in one of the branch wires that come off from the ORG/LtBLU wire.) The wire goes up to behind the dash and I just cut the wire for now.

I cannot figure this thing out and need some help.

 

Google is telling me the EEC is the ECU/PCM.

It could be a internal fault with the PCM/ECU, or it could be a input or output circuit fault.

Disconnect the battery, disconnect the ECU/PCM, reconnect the battery, how many amps is it drawing?

You need a full wiring diagram & disconnect 1 item at a time to see if you current draw drops.

Same goes for the BTN2 fuse, follow the wiring diagram and see what disconnecting items does to the current draw.

 

The EEC has an 6.28 amp draw. I have been trying to find all the wiring diagrams for this but cannot. I will try the ECU/PCM unplug to see if that is the "big" draw. I do need to know the location of the ECU/PCM. Thanks reaper.

 

Remember that the PCM is not only drawing power for digital processing, but also to drive the ignition coils. At 12V, I'd have guessed it would pull more than 10 amps running, but anyway..

Even a marginal alternator will put out 50 amps all day long, and a good one will do 100 amps. If you had a parasitic drain high enough to swamp the alternator and drop the bat voltage a full volt during run you'd have ignited the wiring harness into a spectacular show by now.

Either the alternator is bad (not atypical for a rebuilt alternator to be crap) or the PCM is not turning the alternator on. Check all fuses, there might be a field fuse open. Otherwise, I'd put my money on the alternator. I've heard stories of several being tried before getting a working one.

John