Hey Everyone,
Please forgive me if any of my terminology doesn't make sense or my questions are redundant - I'm an extreme novice here. I work as an auto repair technician, and a coworker of mine has been having an issue with his vehicle and I've gone down a rabbit hole, problem is any question I google results in basic responses of how alternators work - I'm already familiar with the basic workings and anatomy of an alternator. The issue is: he replaced his alternator with a new one due to the output dropping to ~11V with several loads turned on and the vehicle at idle - repair manual for his vehicle specifies no lower than 13V. Per the schematics, the Voltage Regulator is integral to the alternator. We've checked voltage drops across both ground and power circuits and both are within specification. The diagram lists terminals - C to the PCM, B to B+, and L for the dash indicator. No where in the circuit does it show S for signal, and under the PCM input/output list it DOES have Battery Voltage listed under inputs (though I can't find any voltage sensor in any other diagram, assuming it's integral to PCM?). When de-pinning & isolating the C terminal from the alternator harness there is no change - we did this with the hopes that it would throw a "model" type value resulting in an increase of output voltage. The main question I have is there a way to find out what exactly the PCM is outputting under high electrical load, and then to spoof it? - I don't mean to add load to the sensing circuit, but rather change the output of the PCM to the IC. The thought of the PCM not going into a "fail safe" when disconnecting the C terminal is leaving a lot of questions unanswered for me.
I hope this make sense, all basics have been checked to the best of our knowledge.
Thanks!
Please forgive me if any of my terminology doesn't make sense or my questions are redundant - I'm an extreme novice here. I work as an auto repair technician, and a coworker of mine has been having an issue with his vehicle and I've gone down a rabbit hole, problem is any question I google results in basic responses of how alternators work - I'm already familiar with the basic workings and anatomy of an alternator. The issue is: he replaced his alternator with a new one due to the output dropping to ~11V with several loads turned on and the vehicle at idle - repair manual for his vehicle specifies no lower than 13V. Per the schematics, the Voltage Regulator is integral to the alternator. We've checked voltage drops across both ground and power circuits and both are within specification. The diagram lists terminals - C to the PCM, B to B+, and L for the dash indicator. No where in the circuit does it show S for signal, and under the PCM input/output list it DOES have Battery Voltage listed under inputs (though I can't find any voltage sensor in any other diagram, assuming it's integral to PCM?). When de-pinning & isolating the C terminal from the alternator harness there is no change - we did this with the hopes that it would throw a "model" type value resulting in an increase of output voltage. The main question I have is there a way to find out what exactly the PCM is outputting under high electrical load, and then to spoof it? - I don't mean to add load to the sensing circuit, but rather change the output of the PCM to the IC. The thought of the PCM not going into a "fail safe" when disconnecting the C terminal is leaving a lot of questions unanswered for me.
I hope this make sense, all basics have been checked to the best of our knowledge.
Thanks!