Madza Charging System
HI guys just joined the group. Posting this in hopes that someone out there has a "good" scope pattern of the Madza computer controlled charging system. Got called out on the above car with a P2503 code (Gen output voltage no signal). The car is charging at 14.1v. A scope test of the 2 smaller wires going to the alternator with the U-scope (love that scope) shows on the Green wire (command from the PCM) a hashy pattern around the 0 to 1 v range. other comments on another forum say 0 to 1.5 square wave. The yellow/red (signal back to the PCM) should have a 0 to 10v square. Mine was around 0 to 3v square. Both of these voltages are with the car running. Unable to find a "known good" pattern on line , IATN had something close. Many comments about reman alternators. This car has had 3 before I got there. It sure looks like this could be number 4. Does anyone have a Known good pattern of the green and yellow/red wires car running?
Sorry should have said 2005 Madza 6 2.3L
Tell them it needs the Mazda alternator....lol Been kicked hard by this one time. The aftermarket alternators don't give the correct signal back. I can't give you a pattern specifically. I just know that for some reason that 05 Mazda/Ford product needs the factory alternator.