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Having a traction control light that comes on cuts the power to the throttle no codes. Speed sensors steering angle sensor looks good. Thinking I might have an alternator issue. Does this look like a bad diode in the picture I attached
From a coil? You think that can spike the alternator?
Nah, I just mean your scope leads probably picked up on some RFI from the coils.
Only reason I went down the alternator was because if I unplug the alternator the issue goes away
Well isn't that interesting. :huh: The alternator ripple honestly didn't look excessive... I wonder if it's the low system voltage that's preventing the issue from happening.
System voltage stays at 14.4 even with alternator plugged in. Had a spare tire on it thought maybe it was the issue replaced with correct size tire still does it.
On a longer time base is there a repetitive pattern when that spike occurs?
As Tyler I don't think the ripple is an issue at this point. (I believe he meant with the alternator unplugged/not charging the then low system voltage may impede the issue to happen.)
Btw, how did you set up your scope? It seems to be configured at DC voltage??
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
Only thing I noticed is there is 2 readings for each wheel. One is in mph and other rpm. The mph are all the same all 4 wheels but the rpm is different from the left rear wheel. No codes in any module
Yes it’s repetitive on a longer time base. I have the scope ac coupled on a 1 volt scale I’ve run it on a 500 ms time base that drop is repeatable.
For it to be the alternator rectifier you're looking for the problem to happen at a repeatable number of waveform humps, with every sixth hump being the most common. If it's engine noise, or load, related it'll be a repeatable time which corresponds to engine rpm. For example noise from a COP coil will show every 200mS at 600rpm.
