So I have a 2015 EX, and I have a question about the alternators in these cars. So sometimes when I start the car and check the battery with the multimeter is reads at about 13.8 volts. This is with headlights and AC on. Now if I drive around for a bit, and seemingly get the RPMs up, it will eventually ready 14.4 or so. Is this normal? The alternate always reads 14.4 regardless. Is this part of the ELD system?
Alternator Question
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It actually kind of seems like the reverse for me. It seems quicker to but 14.4 during the day and at night more in the 13.8 range. I work nights so my observations might be a little more skewed. Regardless, it seems the variations are normal.
I only see 12 ish after a while, not during startup. During startup I also see the voltage is around 14.
Forget to mention the voltage is read from OBDII
I get high 13s into mid 14s on startup using a multimeter. Apparently this is pretty normal for these cars. I don’t see 12 at all, but I’m not getting readings while driving either.
Yes and yes. The alternators on these cars have a variable output ability, thanks to the electrical load detector. It gives you 0.001 more MPG. This is also why you may see the headlights dim a bit when the a/c compressor comes on.
I kind of figured that was the case, but I just wanted to make sure everything was working ok. Thanks!
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While the ELD is still involved, it is the ECM that is controlling the output of the alternator. The alternator is controlled with LIN protocol, it is a bit more complex than the earlier high/low alternator output. There is also an over running clutch on the alternator as well. The ECM is reading output from the alternator and the ELD and the battery sensor on the negative cable.
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That is interesting to know. As long as things are working as they should, I’m good.
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