Charging issue
01-22-2019, 11:01 AM
#11
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Location: San Jose
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It was all the same. At the moment when I was trouble shooting it, it was 11.8. Running and stopped, on the battery and on the alternator. by the time I got it home and driving it was 10.8.
01-22-2019, 11:23 AM
#12
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If I were you, I'd back probe each of the pins on the generator connector. There should be 2. One is the Gen Control and one is Gen Sense. One wiring diagram that I have for a 2013 (sorry that's all I could get access to) shows that wire with a brown-grey stripe is the Gen Control. Put your positive lead of your multimeter on that (while its connected to the generator that's why you backprobe) with the neg lead to batt negative and see what the reading is. Most multimeters won't give you a true reading of this as it's a really fast on/off switching 12v. But if you see 0 something isn't right. A scope is what you really want. If you have a reading, most likely you are getting proper control via the regulator in PCM. If it's 0 you may have a regulator issue or even a wiring problem.
01-25-2019, 05:56 AM
#14
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I think you are condemning the computer way too fast. Our jeep generators, at least my '14 and i think your 12 has 2 wires coming from the PCM. One is Gen Field Control and one is Gen Sense. The Gen Field Control is a pulse width modulated 12v (really batt voltage). So really you need to validate that signal is occurring from the PCM. An oscilloscope is best as you can see a square wave of 0 then 12v back and forth. Since most people do not have that, you may try a regular voltmeter. it won't be fast enough to see the voltage turning on and off but you should see the meter trying to average a reading or "bouncing" around trying to find a voltage. If you saw 0, that would be an issue.
Last edited by Rednroll; 01-25-2019 at 06:09 AM.