Hi guys. I've got a Nissan optical distributor crank angle sensor I need to
verify if it functions. I was lucky enough to get hold of an L series
optical distributor but the process I'm about to go through is relevant for just
about any Nissan or Datsun optical distributor.
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Hi guys! Neubs from Built On
Purpose. So what this episode is about is just verifying the function of a crank
angle sensor particular the Mitsubishi made one that's found in a number of
distributors Nissan used from the mid 80s through to early 90s I believe. The
system is fairly widely used. So this is an L series distributor. You can see
that's the arrangement there, this is a modified disc by the way, but you can see
this is what it looks like and this is one out of an RB 30 which is a single
overhead cam motor found in Australia. See it's very similar. The disc is a bit
smaller but same principle. So what's common to the NissAn distributors is
they have two rows of slots that they use. The outer row is I think there's 360
slots that's used for the timing which is basically where the crank shaft is
spinning for the the second row of slots, there's a set of six inside. One of...
depending on the system they use they vary but they're used for phasing so
that tells the computer which cylinder is where. Because if you just
have timing that's great, you can sell the crank shafts a certain spot, but that
doesn't help you if you're trying to do Coil Over Plug or sequential
injection so that's why they have the second ring slots.
Obviously if your crank angle sensor fails that can cause a variety of issues
particularly if you're running a standing computer. It can't
determine, the computer can't determine what the engine's doing. So verifying
whether this functions or not is a fairly simple process. It's a digital
wave that comes out, square wave which is, the voltage steps up when the light
shines through a slot and comes back down when it's not. So the process is
simple you could either do it in your car. You might have to take it out loosen it
so you can rotate it because that's what we're going to do we're going to spin
the the chopper disk, the optical trigger disk, in the crank angle sensor and just
measure the voltage. So you can either do that in the car by taking the
distributor out enough that you can spin it by hand or you can take it to a bench.
Which, I am yet to install this in why that's in because, I don't have the
correct drive. It has a unique drive shaft so I need to get one of those
before I can actually fit it in. So I'm going to be testing this kind of on the
bench but using the vehicle power supply to activate the sensor. So with every one
of these Nissan sensors there's four wires that go to it. Black is the ground, red
is a live and there's two other wires that give the timing plus the crank or the
phasing position in the case of the RB30 one you can see it's a plug with four
pins. Okay got my L-series optical distributor set up here to check.
You can see this is the optical disc and the outer row is 360 degree
slits and then you've got the the six inner ones here which represent the
cylinders. I believe these came out on all this
design was used in four cylinder like pulsar, EXAs, Nissan EXAs X's and whatnot. I think
the inner row would have had four slots to represent four cylinders. So this is
the crank angle sensor unit which is a photoelectric LED unit which basically
has little lights that shine through it. It measures when the light shines
through it hits a photoelectric sensor which signals a voltage and essentially
the circuitry within that crank angle sensor which develops a digital waveform
so it's square edges up and down up and down not not a analog waveform. So what
I've got my multimeter set up here. I've got some power and earth hooked up to the
power and earth pins for the crank angle sensor so I'm just merely going to stick
the multimeter on see if I can register a voltage on either of the two wires for
this crank angle. Rightio so about 12 volts or near enough
12 volts hooked up to the live and there's no point reading the ground
because this is an LED system so that will essentially be no voltage on the
other end because LEDs it's what they do yeah. So we'll try the white wire see if
anything happens.
That's not looking real good. That's still in millivolts so, just in case I'm
missing anything, because it's going too fast up and down too fast, I'll use my
max peak hold function of my multimeter.
No nothing on the white wire. We'll try the green wire.
Yeah behaviour is the same.
14.7 millivolts. That's not enough to trigger an ECU so I guess I can
conclude that this crank angle sensor is faulty or failed so I will need to get a
replacement unit if I'm going to proceed using the L series optical distributor
on my Datsun. I can't have a video without demonstrating how one actually
function so I'll grab one of my RB 30 distributors and just demonstrate
behavioral response from one of these optical sensors that actually functions.
)kay so I've just got my distributor set up so what I've got is I've just hooked
up some power and ground to the,to the correct
pins on the distributor and now I'm going to just demonstrate what happens.
I'll just just show you.
I'll just spin it. You can see how the voltage is varying. I'll put the max hold
on so I can demonstrate the high voltange
so it's getting a voltage. At one point forward registers. I'll demonstrate that
again. See it jumping. This is the 360-degree ring so it's very hard to
land on a slot that's open and close but you can least see it and just
demonstrate the maximum hold voltage.
So jumps up to 1.2 9 volts in this instance.
That's what we're looking for so that crank angle sensor is functional and
sending at least a signal for the 360-degree ring. So that's the process I
used to verify for my Nissan crank angle sensor, the optical crank angle sensors,
function. This is relevant to just about any Nissan that runs a distributor with an
optical disc and it's probably relevant to the later model RB Series motors
that run the cam and crank angle sensor attached to one of the camshafts
Ultimately this distributed unit has failed so this this L series distributor,
which I'd like to use as part of my build, will need to have this unit
replaced prior to using it of course. If you found this video helpful I
appreciate a like. Also share it with anyone you might know that could benefit
from this information. If we're meeting for the first time consider subscribing, you
might find my Datsun 240z build is of interest. But having said that, um, thank
you for watching I'll see you in the next one!